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The Rise and Fall of the Muscle Car Part 3: The End

Ryan Lee Price — Thu, 13 Jun 2013 16:41:00 GMT

By Ryan Lee Price

America in 1972 was a drastically different place than it was merely 10 years earlier. A decade at war with no end in sight had taken its toll, as young men became fathers, women became mothers and the idea of hitting the open road and stretching out the V8’s legs had lost some of its allure. Groceries didn’t fit too well in the back of a Corvette, and taking the kids on a cross-country road trip in an AMC with the 401 burbling under the hood became impractical. Nixon visiting China, Watergate, The Godfather, Atari’s Pong, the struggle for civil rights, the massacre at the Munich Olympic Games and the ever-present threat of nuclear war soured much of the sunny disposition of the clean-cut 1960s. It didn’t matter anyway. The muscle car era was under attack from several different fronts, and notable sales figures from the last three years couldn’t even save it.

The first organization that chipped away at the muscle car was the insurance industry. The market strategy for the muscle cars eventually acted as a double edged sword, inviting more people to race meant more accidents with muscle cars involved. The direct effect was the huge opposition to the muscle cars from the automotive safety lobby as well as the insurance industry (remember when the speed limits dropped to 55?). If you couldn’t afford the insurance for a Corvette, you bought a Camaro instead. It is easy to see that muscle cars in the hands of young men weren’t used responsibly. As a result, accident claims increased throughout the 1960s, and so did premiums on certain engines. As insurance rates increased, the popularity of the Challenger’s 426 Hemi and Chevy’s 454 LS6 decreased.

Meanwhile, the horsepower in cars was beginning to falter. In 1973, the Society for Automotive Engineering (SAE) mandated that engines be rated on net horsepower rather than gross horsepower. During the 60s, engine output could be significantly misrepresented, as it was normal practice for car companies to overrate their small block V8s (for sales) and underrate their big block V8s (for insurance reasons). All that stopped in 1972, when cars were required to measure power at the flywheel of the engine with all standard equipment attached. This instantly made everybody’s favorite engine look like it had lost power overnight, as ordinary Americans didn’t understand net versus gross horsepower, they just knew the numbers looked smaller.

The writing had been on the wall since the Clean Air Act passed in 1968. Domestic carmakers added air injection pumps and catalytic converters to meet the clean air standard. Plus, most high compression engines required leaded gas, which would clog catalytic converters and foul oxygen sensors. Some enthusiasts turned to German performance cars (BMW, Mercedes and Porsche) which met the new standards without catalytic converters. Domestic muscle cars couldn’t adapt and sales figures in 1971 were telling. Oldsmobile produced 350hp from its 455 engine but only sold 7,589 cars. Pontiac took things even harder. They finally put the 455 engine, now rated at 335hp, into the GTO and Firebird, but sales still faltered, especially for the GTO. The father of muscle cars sold only 10,532 cars in 1971.

It was obvious the muscle car industry was in trouble, but in 1973 it received the last nail in the coffin. The Organization of Petroleum Exporting Countries (OPEC) announced it would stop selling oil to nations that supported Israel in its conflicts with Arab nations. People panicked, keeping their tanks above half full, and waited in lines at gas stations, even though other sources for fuel were found. Gas prices rose to meet demand, and now it really mattered whether your car was getting only 10-14 miles to the gallon. People wanted smaller cars, and Honda, Toyota and Volkswagen prospered.

However, Pontiac—the rogue division of GM that thumbed its nose at convention throughout the early 60s—had one last card to play. The Firebird Trans Am, in 1973, came equipped with the Super Duty 455, packed with every performance enhancing part from GM’s catalog. At 8.4:1 compression, it was rated at 290hp with 390ft-lbs of torque. It was truly the last muscle car in a now defunct era of automotive history that wouldn’t see a resurgence until the advent of overdrive and fuel injection in the mid 1980s.

But it’s never the same.

Chilton's automotive repair information covers muscle cars and more at: http://www.ChiltonDIY.com.

Not only is Ryan Lee Price a freelance writer specializing in automotive journalism and a former long-time magazine editor, he is part of the technical editorial team that provides content for most all of the ChiltonPRO and ChiltonDIY products. He currently resides in Corona, California, with his wife Kara and their two children.

Cengage Learning Named to the 2013 Training Outsourcing Company Watch List

Chilton_Editor — Tue, 11 Jun 2013 03:08:00 GMT

TrainingIndustry, Inc. Contacts
Ken Taylor, COO
919-653-4992
ktaylor@trainingindustry.com
Jessica Eure, Research Manager
919-653-4984
jeure@trainingindustry.com

FOR IMMEDIATE RELEASE 2013 Training Outsourcing Companies Watch List Announced by TrainingIndustry.com Cary, NC - May 20, 2013 - As part of its mission to continually monitor the training marketplace for the best providers of training products, services and technologies, TrainingIndustry.com is announcing its 2013 Training Outsourcing Watch List. View the 2013 Training Outsourcing Companies Watch List Applicants were selected to the 2013 Training Outsourcing Companies

Watch List is based on the following criteria:

Innovative service offerings
Ability to provide services on a global basis
Unique and proven approach to Business Process Outsourcing (BPO) solutions
Quality of client served

The 2013 Watch List includes a select group of companies poised to capture market share in the training outsourcing space," said Ken Taylor, Chief Operating Officer, TrainingIndustry.com. "Each of these companies provides innovative solutions to a variety of global clients, enabling them to increase their reach - and revenue - year over year." "This year's Training Outsourcing Watch List recognizes eight companies that have developed distinctive and proven BPO solutions," said Doug Harward, Chief Executive Officer, TrainingIndustry.com. "Their extensive range of capabilities and impressive client lists ensure that they will be sharp competitors in the expanding training outsourcing market." For additional information on Top 20 Training Outsourcing Companies, email info@trainingindustry.com or visit www.trainingindustry.com. View the 2013 Training Outsourcing Companies Watch List

About Cengage Learning

Cengage Learning is a leading provider of innovative teaching, learning and research solutions for the academic, professional and library markets worldwide. Cengage Learning's Technology and Trades Professional Business Unit (TTPBU) focuses on developing technician and truck driver training solutions and Chilton automotive repair information for the transportation industries. The TTPBU offers a broad range of "off-the-shelf" products and specializes in delivering customized solutions.

The Rise and Fall of the Muscle Car Part 2: There’s No Limit to Power

Ryan Lee Price — Sat, 25 May 2013 03:07:00 GMT

By Ryan Lee Price

They were called “supercars” or “super compacts” by car writers of the day. It was a fitting term, considering the Y-Body chassis shared by the Buick Special, Oldsmobile F85 and Pontiac Tempest really was the smallest platform those GM divisions offered when introduced in 1961. Three years later, the innovative aluminum V8 block was replaced by conventional cast-iron, and the Y-Body was dropped in favor of the intermediate A-Body chassis. It was these upsized cars, the Grand Sport, the 442 and the GTO (in addition to the Chevelle, Cutlass, and Malibu), that inspired Jan P. Norbye to reference for the first time in the September 1965 issue of Popular Science “the muscle cars of GM.” Two months later, GM was using the term in its advertising, most notably for the 1966 Chevelle SS396 in the November 1965 Car and Driver.

After that, “muscle car” was used for anything that had a big engine, a small chassis and could go stoplight to stoplight quicker than the car next to you. They were mid-sized models with large V8s, special trim, logos and performance options. A good example is the 1970 Chevrolet Chevelle. This model was designed as a mid-sized family car, and the base model was powered by a 230-cubic-inch, inline six engine… or you could team it up with the biggest muscle car engine of its time, the 454 V8.

By the early 1960s, the car culture was in full swing, and besides cruising circuits up and down the main street, drag racing (illegal street and legal strip) had become immensely popular. American manufacturers took notice and began battling for drag racing supremacy… and the fan’s money. By 1964, General Motors had lifted its ban on factory-sponsored auto racing and joined Ford at the track with muscle cars from Oldsmobile, Chevrolet, and Pontiac. Buick launched the Skylark Grand Sport a year later as an option package. Each entry on the strip came with an impressively strong engine. The Dodge Dart 413 cubic-inch B Engine (known as the Max Wedge) could run a 13-second 1/4-mile at over 100 miles per hour. For 1964 and 1965, Ford had its 427 Thunderbolts, and Mopar unveiled the 426 Hemi engine. The public could see its favorite racers at the drag strip on Saturday and buy them from the showroom on Monday.

Though late to the muscle car party and slow from the starting gate with its Rambler Marlin, American Motors gained plenty of credibility in 1968 when it unleashed the Javelin (343 cubic inches) and the AMX (390 cubic inches), both fitted with a variant of its “Typhoon” V8 engine capable of 290 and 315 horsepower, respectively.

One of the models that went through the largest transformation throughout its muscle-car lifespan was the fabled Pontiac GTO. Originally an optional sports package for the Tempest as a response to the Dodge Polara 500 and the Plymouth Sport Fury, the GTO was the innovation of famous executive John DeLorean, who broke company policy by fitting under the hood a 389 cubic-inch power plant (GM previously limited its smaller cars to 330 cubic inches). In 1967 displacement jumped to 400 cubic inches; three years later, the mammoth 455 replaced the 389. The top GTO engine came in 1971 with the 455 (8.4 compression) rated at 335 hp. The 1971 Pontiac brochure declared that this engine produced more horsepower than any other engine in its history.

The auto industry had reached its peak performance, the zenith of its ability (and desire) to offer affordable cars with remarkable power. Unfortunately, it seemed that as soon as the muscle car craze began, many factors forecasted the imminent doom of this short-lived auto phenomenon.

By 1972, the end was very near.

Look for part three of “The Rise and Fall of the Muscle Car: The End.”

Frederick Tudor Was Number One: The Story of the First License Plate in the U.S.

Ryan Lee Price — Tue, 07 May 2013 18:38:00 GMT

By Ryan Lee Price

Up until 1900 in Massachusetts, there were no laws governing the rules of the roads for any type of traffic—carriages, wagons, pedestrians—especially for the burgeoning numbers of automobiles. Not only was it confusing, but a mix of so many modes of transportation was also quite dangerous. For example, the first auto-related death in the U.S. happened in New York in 1899 when 68-year-old Henry Bliss was struck by a taxi near Central Park.

The Massachusetts Legislature passed a bill in 1892, creating a Commission of Inquiry that noted more than 90 percent of the roads were in very poor condition and were only going to get worse as traffic increased. This investigation led to the creation of the Massachusetts Highway Commission a year later; it was one of the first such governmental bodies in the country to “improve the public roads, and to define its powers and duties,” according to the 1893 Commission Report.

Meanwhile, wealthy Henry Lee Higginson (he was the founder of Boston Symphony Orchestra) was growing tired of cars regularly exceeding the speed limit of 15 miles an hour on the roads near his summer estate. He submitted a petition in 1903 about his problem entitled, “A Petition Relative to Licensing Automobiles and Those Operating the Same.”

Higginson had influential friends.

By June of that same year, as a way of creating the revenue to improve the roads, as well as identifying cars involved in newly created traffic infractions, Massachusetts passed a provision in Chapter 473 of the Acts of 1903, creating the “automobile department” (headed by Elting O’Hara, the highway commission board’s stenographer). As Higginson suggested, the new “automobile department” required all automobile owners to register their cars and pay the two dollar fee each year; in exchange, license plates were issued to each registered car. The public had until September to comply. Incidentally, New York had been the first to require license plates in 1901, but relied on the car owners to make their own. Massachusetts was the first state in the nation to issue plates, and by New Year’s Eve 1903, 3,241 automobiles and 502 motorcycles (in addition to 692 chauffeur licenses and car manufacturer licenses) helped deposit $17,684 into the state treasury.

The very first license plate issued by a state government (Number 1) was issued on September 1, 1903, to Frederick Tudor of Brookline. Not only was Tudor just the right man at the right time, but he was working with the highway commission at the time and he just so happened to be the nephew of Henry Lee Higginson.

These early Massachusetts license plates were made of iron and covered in a porcelain enamel. The background was colored a cobalt blue and the number was white. Along the top of the plate were the words, “MASS. AUTOMOBILE REGISTER.” The size of the plate was not constant; it grew wider as the plate number reached into the tens, hundreds, and thousands.

Immediately after the first license plates appeared, drivers in Massachusetts were vying to obtain the lowest numbered plate available as a symbol of status. For the past 20 years, the Registry of Motor Vehicles has held a lottery to clear out low numbered license plates from its inventory. Nearly 5,000 people enter this lottery every year in the hopes of winning a much coveted low-number plate, and even though a three- or four-digit license plate can carry an air of exclusivity to its owner, no one can get any better than Tudor’s license plate Number 1, which is still actively registered to one of his descendants.

The Rise and Fall of the Muscle Car Part 1: An American Phenomenon

Ryan Lee Price — Thu, 11 Apr 2013 16:36:00 GMT

By Ryan Lee Price

Nothing more evokes invokes the salivary glands of an American gearhead than the term, “muscle car.” The throaty roar of an oversized engine, the smell of rich exhaust and the low-slung slant of a car at speed are all American concepts that have galvanized car enthusiasts for the past 50 years. The postwar economic boom in America led to an abundance of industry and a generation enjoying the newfound freedom of the open road. Thousands were trained by the government as mechanics and they enjoyed a penchant for powerful machines, taking their ability to repair the engines of a B17 or the driveshaft of a Sherman tank and applying those skills to cars. Infant racing organizations like NHRA, NASCAR and SCCA encouraged participants to mate larger engines with lighter chassis to see who can go faster, quicker or farther. The age of auto racing had begun on the fringes of society.

Meanwhile, Detroit returned to doing what it was good at, building large, heavy cars with adequately powered engines used to transport people from one location to another. No thought was made for performance, only the production of family cars and the illusion of status. It wasn’t until 1949 that the first large engine was paired with a relatively small car. The Oldsmobile 88 was designed to replace the straight-eight-engine 78 model but was to share the B-body platform of the smaller 76. To power the new model, Oldsmobile introduced the first postwar OHV V8 from General Motors and called it the Rocket V8. The 88 was an instant success. It won six of the nine NASCAR division races in 1949, 10 of 19 in 1950, 20 of 41 in 1952, and was heralded as the first “King of NASCAR.”

Soon, other manufacturers took notice of the Rocket 88’s attention and sales and came up with their own formulas for the early performance cars. Hudson knocked Oldsmobile off the NASCAR podium with the Hornet, powered by a 170-horsepower straight-six with the optional Twin H-Power carburetor (in 1952). The flathead design created 308 cubic inches of displacement and was considered the largest six-cylinder engine in the world; in the hands of precision tuners and experienced racers, the Hornet was unstoppable…until 1955. Chrysler, though a luxury carmaker, aimed its sights on NASCAR with the C-300 (referred to retroactively as the 300A), a “family sedan” designed to win races with its 300hp, 331-cubic-inch FirePower “Hemi” V8. Chrysler christened it the “world’s fastest stock car,” and it was advertised to the public as “America's Most Powerful Car.”

Used to producing small cars that were relatively fuel-efficient, American Motors surprised auto buyers in December 1956 by introducing the Rambler Rebel, which some called “a veritable supercar.” The new 1957 model combined the AMC Rambler’s lightweight four-door body with the manufacturer’s 327-cubic-inch engine (used in the Hudson Hornet), making it the first time that a big block V8 was installed in a mid-size car. Until then, General Motors, Ford, and Chrysler only produced full-sized cars.

What the Rebel—and earlier efforts of the “super car” movement—lacked was styling and the notion of speed, the sizzle that gives anyone who appreciates driving fast the feeling of motion while the car is standing still. As well, they were too heavy, too long, too tall and too expensive to fall into the definition of a true muscle car (even though the term hadn’t yet been coined). All that would change in a few years at the hands of a most capable car designer, Pontiac’s chief engineer John DeLorean.

Look for Part Two of “The Rise and Fall of the Muscle Car: There’s No Limit to Power."

Do All Modern Sedans Look the Same?

Ryan Lee Price — Mon, 04 Mar 2013 18:58:00 GMT

Have you ever walked out of the store to a sea of clones in the parking lot, wondering why your Toyota Camry looks like a Honda Accord, which looks like a Nissan Altima, which looks like an Audi A4? If you remember the good old days of being able to spot the difference between a Chevy and a Ford at a half-mile's distance, then you're not alone. The differences that have kept the manufacturers' designs from looking alike seem to be becoming ever more subtle.

Are the designers out of good ideas? Why aren't there fins, flares or other frills? Aren't they interested in making their cars stand out from the crowd? It turns out that the designers of modern vehicles are guided by at least five considerations: profit, safety, reliability, fuel economy and you.

Some design and engineering ideas never make it past the accountants. Lightweight, strong materials such as carbon fiber, titanium, magnesium and aluminum alloy are used sparingly because of their relatively higher costs compared with steel and plastic. Unique body structures are considered in relation to competitive models. Does the class leader have a similar design treatment? Can the car be sold internationally? Each unique idea had better meet business objectives and have an influential champion behind it or it won't be put into production.

Through focus groups, consumer marketing panels and car-buying surveys, people say they are not as interested in flashiness as they once were. With the exception of a few design variants, they want functionality, reliability and efficiency. The road-going lust of the car culture is waning, as the average age of first-time drivers steadily gets higher, more people take public transportation, and some would-be drivers decide to forgo the costs and hassle of car ownership altogether. For the most part, people want transportation, not necessarily to make a statement. As a result, car designers play it safe and pen a car for the majority rather than a narrow niche. Consider that the milquetoast Honda Civic sold 10 times the units as the funky Hyundai Veloster.

Fuel economy is the largest factor to be considered when designing a modern sedan. To create a more efficient vehicle with high mpg, all new car designs spend considerable time in a wind tunnel. By shaving off fractions of an inch to body panels, designers try to come as close as possible to a perfect aerodynamic profile (the teardrop) in an effort to obtain a sleek coefficient of drag, the measurement that determines how much air passes around a car. Since hardly anybody would buy a car shaped like a teardrop, designers have to compromise. The end result is duplicated by manufacturers around the world.

Manufacturers are reaching an increasingly global vehicle market, so safety standards in this and other countries must be considered. For example, cars bound for Europe need to be designed considering pedestrian impact. Europe requires that the nose of the car must strike a person above and below the waist at the same time to increase the chance that a person will land on the hood as opposed to being swept under the car. This results in chunky bumpers and blunt facades. In an extreme example, Jaguar added a "pedestrian deployable bonnet system" to its XKR in 2007. The device raises the hood several inches when bumper sensors detect that it has struck a pedestrian, allowing for a buffer between the unfortunate pedestrian and the not-so-forgiving engine below.

To test your ability to discern design differences, there are eight random sedans in the picture at the beginning of this article. Which car is which? Please provide your best guess and visit our Facebook fan page at https://www.facebook.com/ChiltonAutomotive/posts/128052957375438?comment_id=114342&offset=0&total_comments=4 for the answers.

A History of the Invisible Wall: Our Struggle with Aerodynamics, Part 3, Aerodynamics in a Nutshell

Ryan Lee Price — Wed, 27 Feb 2013 21:05:00 GMT

By Ryan Lee Price

Have you ever pushed your hand through water and noticed the divot you created (and noticed how the water swells up in front of your hand as it moves)? The water attempts to fill in behind your hand, but your hand is always one step ahead. As a result, a continuous vacuum sucks in the opposite direction of your hand, pulling water with it. This is the essence of Bernoulli’s Principle and the basics of aerodynamics as we know it today.

In 1738, scientist Daniel Bernoulli discovered that for a given volume of air, the higher the speed the faster the air molecules are traveling, the lower the pressure becomes. For nearly three hundred years after Bernoulli, many talented mathematicians added to the principles of aerodynamics: Leonhard Euler’s inviscid flow (1750s), Navier and Stokes’ motion of fluid (1840s), Hermann von Helmholtz's concept of vortex filaments (1858), Frederick Lanchester's concept of circulatory flow (1894) and to the Kutta-Joukowski circulation theory of lift (1906).

If you were to place any modern “three-box-design” car (meaning it has a hood, a cabin and a trunk, all roughly box shaped) inside a wind tunnel, air would flow up the hood, over the windshield and across the roof. The majority of the airflow leaves the car at the end of the roof line. The slope of the rear window and deck lid creates a low pressure area around the back of the car. This low pressure acts as a vacuum that sucks some air back toward the car, thus creating turbulence.

To know what happens at the rear of your car at speed, you have to start at the front. To help answer this, let’s turn to one of the world’s least aerodynamic cars, an old Volkswagen Bus. As the blocky shape of the Bus drives down the road, it literally punches a hole in the air, which is forced out of the way via the six sides of the box. This force is called “frontal pressure,” because air slows down as it approaches the front of the Bus, causing more molecules to be packed into a smaller space. At speed, the space directly behind the Bus is nearly devoid of air. This empty space is caused by the air molecules not being able to fill the hole as quickly as the Bus can make it. It is called flow detachment.

Now, back to the three-box car. As the air flows over the hood of the car, it loses pressure and creates a small lifting force (like trying to suck the hood off the car), but when it reaches the windshield, it again comes up against a barrier and briefly reaches a higher pressure. The higher pressure area in front of the windscreen creates a down force. This is like pressing down on the windshield and slowing the car, while the front end is lifted upward. As the higher pressure air in front of the windshield travels over the glass, it accelerates, causing the pressure to drop. This pressure reduction lifts the car's roof as air passes over it, while air passing underneath the car adds additional lift. These forces create a tight-wire act, balancing between too much lift and too much drag.

Colin Chapman invented a new concept to provide down force without altering drag, called ground effect. He incorporated an air channel into the bottom of his Lotus 72 racer, narrow in front and wide in the rear. Since the car’s bottom was nearly touching the ground, the combination of channel and ground formed a closed tunnel. When the car moved forward, air entered the tunnel in the nose and expanded outward toward the tail. Air pressure was reduced at the tail, creating down force.

The ultimate example of the down force concept was the Brabham Alfa BT46B, designed by Gordon Murray for the 1978 Swedish Grand Prix, which actually used a cooling fan to extract air from the skirted area under the car, creating enormous down force and hence amazing handling capabilities. After technical challenges from other teams, it was withdrawn after a single race and the practice was banned.

On the three-box example, once air makes its way to the rear window, the drop created by the window and the flat trunk of the car leaves a sizable vacuum, a low pressure space that air is not able to fill quickly. The airflow detaches and the resulting lower pressure creates turbulence, which always deteriorates the drag coefficient.

For perspective, the worst possible aerodynamic streamlining might be expected from a parachute, which is designed to maximize wind resistance. The Coefficient of drag (Cd) of a parachute is about 1.35. The least possible resistance might be from an airplane wing, which has a Cd of about 0.05. Automobile Cd figures lie between these two extremes. In the past 80 years, automakers have managed to cut Cd figures for production models nearly in half, from about 0.70 to about 0.30. In a practical sense, gas mileage increases by five percent for every 10 percent improvement in aerodynamics, and in times of increased fuel costs, driving a car with a high Cd can be, quite literally, a drag.

A History of the Invisible Wall: Pursuit of Aerodynamics, Part 2, Going Mainstream

Ryan Lee Price — Mon, 18 Feb 2013 16:42:00 GMT

By Ryan Lee Price

Aerodynamics was great for racecars, airplanes and boats, but through the 1910s and 20s, car design was still function over form. Production car designers drew the square-shaped car built on a carriage chassis with foot boards, sunshades on the exterior of the windshields, detached headlights and rear lights perched on the fenders.

In the 1930s, automobiles began to resemble carefully designed pieces of art. Cars appeared with smooth rounded edges, graceful arching fenders, exterior lighting built into the bodywork. The radiator grille and shell were raked back slightly, which made cars look like they were going fast when they were standing still. The front office learned quickly: speed sells.

Streamlined designs became eye catching. Chrysler in particular captured the techniques of aerodynamics and streamlining in its 1934 Airflow model. The Airflow, although a big step in aerodynamics in America, was poorly received and dropped soon thereafter. But revolutionary body styling still spread. Moving passengers forward allowed “fastback” lines, with grilled radiators and skirted fenders. Cars like the 1936 Lincoln Zephyr set styling patterns for years, though most of these designs only gave the appearance of drag reduction; few examples provided significant results.

In Europe, Auto Union (the predecessor to Audi) made considerable progress in the mechanical aspects of their cars, but its engineers were seeking new methods of styling and materials selection to increase efficiency and speed. Using Paul Jaray’s patents, optimum aerodynamic properties were first calculated by theoretical methods, then tested in the wind tunnel. Using these methods, the production version of the DKW F9 achieved an astonishing drag coefficient of 0.42, a dramatic improvement over the F8’s 0.58.

Though the years, countless factors have shaped the way cars are designed, from increased safety regulations to the price of oil. In most of the passenger vehicles we see on the road today, aerodynamics plays a comparatively minor role in the overall design of the vehicle. John H. Lienhard, a professor of mechanical engineering and history at the University of Houston and author of “The Engines of Our Ingenuity” adds, “It took time for engineers to see that they had to smooth the bottom of an automobile as much as the top. It took time to see that sharp corners on the front of a car were terrible drag-inducers. Only in the last generation did 18-wheelers sprout those strange-but-effective, drag-reducing cowls over their cabs.” We have come to associate an appealing car design if it emulates the lines of a racecar, and no other aspect of a car’s profile better illustrates this than the distance between the wheel arch and the top of the fender. The perception of speed increases as that distance decreases.

Throughout the 1950s, a typical prototype sports racing car was small, lightweight, front-engined, and wrapped in a nicely designed aerodynamic shell. Due to relatively inefficient engines, racecar designers made cars look aerodynamic so that they cut through the wind, making up for horsepower deficits. But racecars of the era were prone to too much positive lift, causing them to launch into the air even if slightly provoked at high speeds.

In 1956, engineer Michael May thought that by constructing an airfoil, flipping it over so that it produced a negative force towards the ground, and mounting it onto his Porsche Type 550, he could utilize this down force to improve traction, grip, and handling. But race organizers kept his rear wing design off the track because the wing “restricted the view of the drivers behind him.”

It wasn’t until the 1960s that auto makers noticed that if they reduce the slope of the back of the car to 20 degrees or less, the air flow will follow the roofline and drop off the back of the car, greatly reducing drag. It was called a Fastback design, and an excellent example is the Porsche 935/78, better known as the “MobyDick.” The Fastback design isn’t without its flaws, especially in lift. Because it has a very large surface area in contact with air flow it suffers from a low pressure on top of the car. Usually, wings are used to combat this problem. It seems that good drag and good lift are mutually exclusive, you can't have both of them in equal amounts at the same time.

In 1962, Ferrari engineers discovered by adding an airfoil to the rear end of their Ferrari 246SP endurance racer they were able to direct the majority of the air flow away from the rear of the car, thereby reducing drag and lift. This technology trickled down the following year to the 250GTO road car, which incorporated a small duck tail rear wing. In 1966, Jim Hall mounted a wing onto his 2E Can Am Chaparral, competing well in the Can Am championship and further proving the concept. By 1968 wings started to show up on many Formula One cars, firmly establishing downforce airflow design.

In 1969 Porsche introduced the 917 to international sports car racing, a car with a reliable, low horsepower engine paired with sleek, low-drag bodywork. The combination worked well, but they couldn’t get the championships the factory wanted. They switched to a higher-horsepower engine, but the car was then plagued with aerodynamic instability problems (drivers soon named the car “The Ulcer”). Through wind tunnel testing, the front and rear bodywork was restyled and the car soon dominated the Sports Car World Championship in 1970 and 1971.

However, the wing did not get popular with the public until Porsche launched its 911 RS 2.7 in 1972, whose big duck tail reduced lift by 75 percent at high speed. A trademark of the 911, the “Whale Tail” appeared the following year on the RS 3.0 and it completely eliminated lift at the rear tires. It seemed that form had finally caught up with function in car design.

Stay tuned for Part 3 of “A History of the Invisible Wall: Aerodynamics in a Nutshell”

A History of the Invisible Wall: Pursuit of Aerodynamics, Part 1, The Early Years

Ryan Lee Price — Tue, 12 Feb 2013 04:38:00 GMT

By Ryan Lee Price

Though the term “aerodynamics” is less than 100 years old, people have been experimenting with the concept for thousands of years. Appearing in Norse legends, a Finnish blacksmith named Ilmienen is said to have produced metal wings with which to fly; Shun, the emperor of China in 2000 BC was taught to fly by two princesses of his court, and 500 years later, Chinese writing depicts a flying cart with wheels that resemble propellers. Kites are believed to have been invented in China around 400 BC by Mo To Tzu, while in 67 AD, as described in Octave Chanute’s 1880 book La Navigation Aerienne, Simon the Magician made one of the earliest recorded attempts at flight with a primitive glider.

Hundreds of years later, DaVinci designed parachutes and helicopters after observing the “vital force” of birds, but most notably sketched what he called an ornithopter, whose pilot flapped the wings via pulleys. A French locksmith named Besneir created a simple glider in 1678. Francois Blanchard expanded DaVinci’s ornithopter by adding a balloon in 1781, and American Dr. John Jeffries, four years later, was the first to cross the English Channel in such a device, later proclaimed the greatest feat of the century. The Wright Brothers came along, and although they didn’t invent the airplane, they ushered in the age of modern flight, aeronautical engineering, and paved the way for cars to cut through the very same atmospheric barrier that airplanes needed for flight.

At the same time the airplane was taking off as a serious form of machinery, on the ground, the automobile was gaining popularity. There are countless examples of racecars with streamlined designs borrowed from boats: the 1916 Indy 500 winner, a Peugeot with a boat-tail tapering aft of the rear wheels. As early as 1907, a streamlined racing car called the Rocket reached 132 miles per hour before it became airborne.

To a racecar designer, having their car slip easily through the air was of vital importance. However, early production car designs focused their attention on how well the engine and transmission could punch a hole through the same air.

It wasn’t until 1921 when Edmund Rumpler produced the first truly aerodynamic car for the masses called the Rumpler-Tropfenauto, which loosely translates into “tear-drop car” (when viewed from above). The car caused a sensation, but Benz’s attempt to commercialize it failed, thanks to its futuristic design. The aerodynamics of his cars were better than that of most cars built around 70 years later, as it was reported that bored engineers at Lockheed’s wind tunnel in Georgia strapped one of the few surviving examples to the wind tunnel. To their surprise, it produced a coefficient of drag (Cd) value of 0.27. Compared to modern cars with the benefit of computer-aided designs, this is a significant increase (Cd averages around 0.32 today). Around 100 examples of the Tropfenauto were built, and several of these unique vehicles can be seen set ablaze in the final scenes of Fritz Lang’s movie “Metropolis.”

If Rumpler started the trend toward the efficiencies of aerodynamics, then Paul Jaray, a former Zeppelin designer, gave it a big push into the mainstream. Stay tuned for Part 2 of “A History of the Invisible Wall: Aerodynamics Goes Mainstream.”

Which Basic Hand Tools Do You Need?

chilton_marketing — Wed, 03 Oct 2012 17:29:00 GMT

As you begin to perform maintenance on your car or truck, you might need to buy some more tools. Purchase your tools gradually, so that you gain the confidence to use the tools, realize their value, and determine your needs before buying more. To begin, you should have the following hand tools for basic vehicle maintenance. I will explain how to select electronic diagnostic tools in another article.

Recommendation: Buy quality tools that have long-term (even lifetime) warranties from companies with solid reputations for good customer service. Cheap tools can cause problems during your work, commonly not fitting fasteners properly, bending or breaking during use, and inflicting pain or injury on the user.

§ Forged steel combination open-end and box-end wrenches in 7 mm – 19 mm sizes (choose inch sizes for older American vehicles).

§ Hex key wrench set.

§ Assorted screwdrivers: standard slotted-type, Phillips head, Torx^®, long and short bladed. Many or all of these types can belong to one screwdriver with interchangeable blades or bits.

§ Assorted pliers, including long-nose (also called needle-nose), channel locking, gripping or locking pliers, O-ring pliers, and wire cutters.

§ Forged steel 6 or 12-point socket set with a fine-tooth ratchet-type wrench; short and long extensions and a ¹³/₁₆ in. or ⁵/₈ in. spark plug socket (depending on plug type).

§ Click-type torque wrench for tightening bolts to proper specifications.

§ Hydraulic jack (with the capacity to lift at least half of your vehicle’s weight). Invest in a good jack, because if it fails, your vehicle may fall to the ground when you are not prepared to place it there.

§ Jack stands that can easily support the weight of the vehicle. Don’t scrimp on jack stands either; they can save your life.

§ Oil filter wrench. Check your oil filter size and type before buying this wrench. The strap-type wrench doesn’t fit all filters. You might not even need a special wrench for cartridge-type filters.

§ Spout or funnel for pouring fluids.

§ Large container for catching oil and other draining fluids; even better is a recycling container system, which some local governments distribute to encourage used oil recycling.

§ A shop light. It should be small enough to fit in tight spaces, tough enough to withstand some knocking around, and convenient enough to attach under the hood or anywhere it is needed so your hands are free to work.

Here is one final word about how much to pay for your tools. All the tools above, if purchased new, should cost several hundred dollars. Add a rollaway tool box to keep them in and the total will exceed a thousand dollars. But they can pay you back in just a few repair jobs. If you buy quality tools, they will last longer than your cars—or even you. I still use some hand tools that were given to me by my father, and some of those were given to him by his father.

Chilton Partners with WHI Solutions to Add Real-Time Parts Pricing and Inventory to ChiltonEstimating and ChiltonPRO

chilton_marketing — Fri, 17 Aug 2012 18:08:00 GMT

Clifton Park, NY – April 26, 2012 - Chilton, part of Cengage Learning and an established leader in reference sources for automotive professionals and Do-It-Yourself (DIY) automotive enthusiasts, today announced an agreement with WHI Solutions to provide updates to Chilton’s ChiltonPRO and ChiltonEstimating products. Through this new agreement, all ChiltonPRO and ChiltonEstimating users with WHI/Nexpart credentials will now have the ability to create estimates using real-time parts prices and have access to distributor’s inventory.

Now the industry standard, Nexpart from WHI Solutions has accelerated Internet parts ordering and allows service dealers, car dealerships, fleets, national accounts, government agencies and distributors to order parts quickly and easily over the Internet from their parts suppliers. This service, now incorporated into ChiltonPRO and ChiltonEstimating, allows customers to obtain immediate parts pricing and inventory to include in customer estimates. Chilton customers will simply need to add their WHI/Nexpart credentials (provided by distributors) into the administration page of ChiltonPRO or ChiltonEstimating to access these new features.

“We are excited to incorporate the proven technology of WHI Solutions with two of our best-selling products,” said Greg Clayton, vice president, Cengage Learning. “We work hard to continually add content and increase the functionality of our products – in this case ChiltonPRO and ChiltonEstimating. Users will find that it is now easier than ever to diagnose, repair and create accurate estimates for their customers, with these new features from WHI Solutions.”

ChiltonPRO is a cost-effective, electronic repair information system for professional technicians. The product provides Chilton’s entire suite of content including technical service bulletins (TSBs), repair information, diagnostics, maintenance schedules, labor times and estimating. Similarly, ChiltonEstimating is a convenient online tool to aid professional automotive technicians with estimates, work orders and invoices, using Chilton’s trusted labor times. It provides easy access to current labor times with all content available online and can be easily accessed through any web-enabled computer. Both of these products will now also feature integrated, streamlined parts pricing and distributor inventory through Nexpart.

For more information on this new partnership, ChiltonPRO, ChiltonEstimating or any other product from Chilton, please visit www.chilton.cengage.com.

About Cengage Learning and Chilton

Cengage Learning delivers highly customized learning solutions for colleges, universities, professors, students, libraries, government agencies, corporations and professionals around the world. These solutions are delivered through specialized content, applications and services that foster academic excellence, professional development, and measurable learning outcomes. Chilton, part of Cengage Learning, is an established leader in reference sources for automotive professionals and Do-It-Yourself automotive enthusiasts. For more information on Cengage Learning please visit www.cengage.com. For more information on Chilton products, visit www.chilton.cengage.com.

How Tire Professionals Replace Tires

Ryan Lee Price — Mon, 13 Aug 2012 02:46:00 GMT

Story and Photography by Ryan Lee Price

So, you’ve got a set of four new tires and you want them wrapped around the wheels that are already on your car. It’s a common situation, but the trouble is your old bald tires; they’re still on the vehicle, right? If you happen to own tire irons, a big hammer and some sizeable biceps, you might be able to break the tire bead seals, but you could damage the wheels quite easily. Plus, the odds are good that you don’t have a tire balancing machine… they’re expensive and take up a lot of room. Instead of going DIY, in this case, it is much more fun to watch it being done. Let’s take an inside look at how professionals replace tires.

The first step, of course, is removing the wheels from the car. At a shop, they jack the whole car off the ground to make it easier to balance the tires on the car itself (more on this later). Most of the action takes place around two machines. The first piece of equipment the tire visits is the tire changer, which costs a couple grand. After the air is let out of the tire (by removing the valve stem completely), the tire is lined up with the side-mounted bead loosener, which uses a pneumatic arm to pinch the tire enough to break its seal on the wheel. The shovel-sized head on this mechanism replaces you hitting the tire with a hammer.

Once the bead is broken on both sides and the tire is flopping around the rim, it is hoisted up on the table top of the tire changer, and a pickup truck or SUV wheel/tire combination weighs nearly 100 lbs., so it can be rather cumbersome to wield around. There are four rubber-tipped clamping arms that grab and secure the wheel without scratching it, while the operator slips between the wheel and tire separation head that has a polymer insert to further protect the wheel. With a flick of the foot petal, the wheel begins to turn, while the stationary separation head pulls the tire from the inside of the rim to the outside. Sometimes, the tire needs a little coaxing with the tire irons.

The process is repeated for the inside bead as well, pulling the tire completely off of the rim from the top. A brand new inflation valve is inserted and the new tire is prepped for its place on the rim by bathing the bead with soapy water. This helps the tire slip over the rim easier. With the help of a couple of tire irons, the tire changer's separation head becomes a joining head, pushing the tire's beads over the rim. With a tire this size, it can be a tough job.

The pin in the new valve stem is temporarily removed so 50 lbs. of air can be pumped into the tire quickly. Then it is off to the balancing machine. The process is simple in a shop but virtually impossible to do at home without special equipment. Balanced tires not only ride smoother and safer but last longer and offer an even wear throughout the tire's life. The tire and wheel are clamped onto the spoke via the wheel's lug pattern and the machine verifies electronically that the wheel is perfectly centered.

Once the balancer is started, it only takes about 10 seconds for the machine to measure the tire's balance and not only suggest the amount of weight needed to fix the imperfection in the tire but it also shows exactly where the weights need to be added. Each square of weight equals one-quarter ounce and is glued to the inside of the wheel, out of sight.

Now the new tire/wheel combination is ready to be fitted back on the car, where it will be tightened to the correct specification. Normally, we encourage you to tackle projects yourself with the help of our extensive database at http://www.chiltondiy.com. However, some things — like replacing tires — are best left to the professionals with the big, expensive machines.

Top 5 Brake Complaints and How to Resolve Them

Jim Marotta — Wed, 25 May 2011 16:14:00 GMT

Story and Photography by Jim Marotta

I think we can all agree that the braking system is the most important safety device on any vehicle. Since people place such a high value on their car's ability to slow and stop, it is smart to pay attention when they complain about the brakes.

Let's review the five most common brake complaints and how to resolve them.

1. Noise

Brake noise, or squealing, is the most obvious problem to drivers. Unwanted movement of brake components causes the noise. What's the solution? Keep brake components in place per factory specifications and properly prepare surfaces during service.

According to Chuck Kennedy, Bendix Technical Training Manager, "Today's brake systems are very sensitive to rust and corrosion and should receive a thorough cleaning in preparation for fresh lubricant, hardware, and friction material. Residual rust or corrosion left in critical areas can begin to cause brake issues almost immediately."

In addition to the normal inspections for binding, corrosion, lack of lubrication, and worn or damaged components, clean the caliper moving parts and retaining hardware. Clean pin bores with a round wire brush and cleaner to remove old lubricant and corrosion.

Caliper pins can cause binding. Clean the caliper moving parts and retention hardware of dirt, corrosion and rust. Clean pin bores with a round wire brush and cleaner to remove old lubricant and corrosion.

Pad abutments need to be clean and smooth, whether they are part of the caliper bracket or steering knuckle. If there are notches or grooves caused by pad movement, replace these parts. Damage like this can cause excessive pad movement that leads to noise and vibration.

It may be counterintuitive to clean a new or freshly machined rotor with soap, warm water, and a stiff brush, but this simple step removes fine metal particles from the surface and pores, which if left there, can embed in the friction material, causing brake noise.

Clean, inspect and adjust rear calipers or drum brake systems before the vehicle gets back on the road. If there are grooves on the backing plate shoe support pads, replace the backing plates. This prevents shoe chatter and improper brake shoe return, which leads to grabbing and premature shoe failure.

2. Pulsation

Pulsation is another issue that is obvious to the driver. Check for rotor lateral runout and thickness variations that point to pulsation issues. Do not forget to check the hubs. Hubs can be the culprit while the rotor shows the symptoms.

Checking for rotor thickness variations will help diagnose pulsation issues.

Use a polishing pad to clean as much rust as possible from the hub face and next to the studs. Leaving corrosion in these areas is one of the top causes of pulsation.

An often overlooked area is the wheel hub mounting pad. If there is rust or debris in this area, it can lead to rotor distortion and pulsation just as easily as if debris were left on the hub.

Another common cause of pulsation is uneven tightness of wheel lugs. Lighter components on today's vehicles can be easily distorted. Eliminate this issue by lightly seating and then torquing wheels to specification in two stages. On wheels with lug-centric hubs, rotate the wheel as the lugs are seated to help keep the wheel centered on the hub.

What do you do if all else fails and there is still pulsation? Check the tire and wheel assemblies for speed-dependent, loaded, radial force variations. A tire or wheel rim out-of-round or imbalanced can cause a pulsation similar to the pulsation caused by rotor problems.

3. Dust

When applying braking force, small amounts of material gradually abrade from the brake pads. This material, known as "brake dust," usually deposits on the braking system and the surrounding wheel.

The proper friction material choice can affect dusting. Different brake pad formulations create different amounts of dust, and some formulations, particularly metallic brake pads, create more dust than others. Ceramic brake pads contain significantly fewer metal particles, and therefore produce less abrasion of surrounding metal parts.

Rob Backode, Director of Product Management for Bosch Automotive Aftermarket Brake Components reports that "The number of complaints about brake dust is far, far fewer with more service shops installing ceramic-type brake pads."

Brake dust can be more than just a visual nuisance; it can badly damage the finish of most wheels if not washed off. Removing brake dust can eliminate other problems and avoid customer complaints.

Some technicians tape off the brake shoes to prevent contamination during service.

4. Excessive Wear

Common complaints due to excessive wear are usually due to lack of maintenance, hard driving style, or vehicle usage characteristics. Brakes on one vehicle may last substantially longer if the owner drives it easy or takes more highway trips. If the owner overloads the vehicle, makes short, stop-and-go trips, or leaves one foot on the brake pedal while driving, the pads will have more wear and failures from the abuse.

Common complaints due to excessive wear are usually due to lack of maintenance, driving style, or the way the vehicle is being used.

Residual pressure trapped in the hydraulic system can lead to excessive wear and premature failure of friction materials. Quickly determine whether it is a mechanical or hydraulic issue by cracking a bleeder screw on a caliper that shows drag. If fluid comes out and the caliper releases, then a component is restricting fluid return to the master cylinder reservoir. If no fluid escapes and the drag remains, then it is a mechanical issue within the caliper or slides.

Residual pressure trapped in the hydraulic system can cause excessive wear and premature failure of friction materials and surfaces.

5. Stopping Performance

Stopping performance is crucial for today's high performance vehicles and driving conditions. Poor performance can be related to a previous brake job that was done improperly, failing components, vehicle overloading, or installing the wrong type of friction material. Proper inspection, preparation, and break-in are the best ways to overcome these issues.

Pad burnishing or break-in is recommended by many original vehicle manufacturers, but not all. When recommended, a proper burnishing or break-in of the friction material and rotor surface will enhance brake performance, reduce noise, and give the best life possible for the pad materials installed. Burnishing works by mating the two surfaces together to allow proper heat dissipation. It also transfers a film from the friction material to the rotor surface that will enhance its performance.

Old Concerns, New Problems

While there are issues we no longer have to deal with on today's vehicles thanks to technological advancements, some changes create new challenges. Improvements in materials such as rubber and composites lengthen the service life of brake components. Modern, synthetic lubricants give more protection, last longer, withstand higher temperatures, and are compatible with rubber components.

Lubricants have improved in recent years, give more protection, last longer, sustain higher temperatures, and the synthetic compounds are compatible for use with rubber components.

The smaller components and lighter weight of the brake components and the vehicle itself drive many of the changes. Less mass increases the chance for noises to occur. Vehicle manufacturers use more anti-rattle clips and hardware to help control brake noise. Brake systems run at much higher temperatures, requiring improved lubricants.

Pulsation issues increased when rotors went from integral hub/rotor assemblies to over-the-stud mounted assemblies. Corrosion between the assembled hub, rotor, and wheel gives rise to runout and pulsation issues.

As vehicles continually change, we may leave some problems in the past, but we look for new tools, procedures, and information to solve issues on modern cars and trucks. Servicing modern vehicles is more exacting and detail-oriented. Leaving out important steps increases the chance for customer complaints and comebacks. Thorough inspection, diagnosis, and repair procedures are the best way to keep customers satisfied and their vehicles performing up to their expectations.

Resolve your customer's major and minor brake complaints with a subscription to ChiltonPRO, the smart technician's guide to new technologies and old. Just click here to see ChiltonPRO and learn what's coming next to your service bay.

A muscle car enthusiast and drag racer, Jim Marotta is a freelance automotive writer with more than 20 years experience in the automotive industry.

Eight A/C Service Mistakes That Can Make You Sweat

Jim Marotta — Tue, 29 Mar 2011 20:24:00 GMT

By Jim Marotta

What was once a basic system to heat and cool the interior of a vehicle has become a multi-zone, automatic temperature control system with cabin air filtration. No longer are a few tools and some basic knowledge adequate to diagnose and service modern climate control systems. Without proper tools and up-to-date information, mistakes are inevitable.

Let's take a look at the eight most common mistakes techs make when servicing climate control systems.

1. Not Identifying the System Refrigerant

Do you know what type of refrigerant is in your A/C system? This is important information because if you mix refrigerants, the system will not function properly and the wrong refrigerant may damage components. More importantly, if there are non-approved hydrocarbon blend refrigerants in your A/C system, it could be explosive!

The only way to know what is in an A/C system or container is to use a refrigerant identifier. Owning one also helps you to avoid damage to your air conditioning service equipment from contaminated refrigerant and prevents contamination of your refrigerant supply, warranty loss on recovery equipment, and even risk of injury.

The identifier found contaminants in the system and registered "FAIL," telling the tech to evacuate and replace the refrigerant.

2. Not Using the Specified Lubricant

The manufacturer of the vehicle or A/C compressor designs each air conditioning system for a specific viscosity and type of lubricant. While some aftermarket lubricant suppliers claim their oils are universal for every application, these lubricants will usually work best for one situation, but not nearly as well for others.

If you are servicing an older vehicle and CFC-12 is the refrigerant, manufacturers specify the use of mineral oil as the lubricant. A vehicle retrofitted for use with HFC-134a uses polyalkaline glycol (PAG) oil. For vehicles originally equipped with HFC-134a use the OEM-specified viscosity PAG lubricant.

In general, manufacturers offer three viscosities, or thicknesses, of PAG oil. The smaller number indicates less viscous oil. Many Nippon-Denso style compressors use the 46 centistoke lubricant; this includes many of the Ford and Chrysler compressors. Several import and aftermarket compressors use the 100 centistoke lubricant. General Motors uses the 150 centistoke lubricant primarily on the Delphi-Harrison compressors.

The manufacturer of the vehicle or compressor determines the viscosity and lubricant type. While lubricant suppliers claim their oils are universal, each lubricant will usually work best for one situation.

3. Improperly Recharging Systems

Early A/C systems required large quantities of refrigerant; 3 lbs. or more was not uncommon. Charge tolerances for these systems were also reasonable. A simple digital scale and charging station could easily handle the service.

Today most passenger cars and light duty trucks carry less than 20 ounces of refrigerant, or just over 1 lb. One of the smallest capacity systems on the market is the Toyota Yaris, which runs on approximately 11 ounces. With the accuracy of some older scales at plus or minus 0.2 lbs., or more than 3 ounces, the possibility of over- or undercharging a system becomes a definite possibility.

Just 2 ounces of over- or undercharging reduces performance, and 2 ounces of undercharging also affects compressor lubrication. For greater accuracy, use a charging station certified to SAE International standard J2788.

Just 2 ounces of over- or undercharging reduces system performance, and 2 ounces of undercharging also affects compressor lubrication. For greater accuracy use a charging station certified to SAE standard J2788, such as the one shown.

4. Not Using Approved Refrigerants

At present, there are only two OEM recommended refrigerants; CFC-12 and HFC-134a, with a third to come shortly. OEMs specify CFC-12 for use in vehicles manufactured prior to 1992, when they changed to HFC-134a. Currently HFC-134a is the only refrigerant automakers specify for use as a retrofit refrigerant for CFC-12 vehicles. Automakers and compressor manufacturers design current HFC-134a mobile A/C systems only for HFC-134a refrigerant and the specific lubricant, polyalkaline glycol (PAG).

Although companies market a number of other refrigerants that contain hydrocarbon blends, the EPA does not accept them. Beware of inexpensive refrigerants being advertised as "Accepted." Use trustworthy brands.

5. Using Components with Incorrect Performance Specifications

In many cases when servicing an air conditioning system, replacement parts are expensive and there's an incentive to save money by purchasing inferior parts. In a typical expansion valve type air conditioning system, refrigerant absorbs heat in the evaporator. Afterwards, the refrigerant gives up the heat in the condenser and the process continues in a cycle.

If either of these heat exchangers, or the radiator-the third heat exchanger- does not match OEM specifications for performance, the system will not operate properly. A part may look the same as the original and bolt in place correctly, but that does not mean it meets OEM performance. Check the specs and avoid the hassle.

6. Not Performing a Thorough System Evacuation

Depending on the ambient temperature, many older recovery/recycling machines in operation today may only recover 50% of the refrigerant from a system. Even the best machines that far exceed the old SAE J2210 standard requirements may leave up to 30% of the refrigerant behind.

Here is an example: In a system with a 16-oz capacity and 12 ounces remaining in the system, you might unknowingly recover only half the charge. That leaves six ounces of refrigerant remaining in the system. When you recharge the system with 15 oz. of fresh refrigerant, the system will have 21 ounces and be overcharged by 38%.

Fortunately, if you purchased a recovery/recycle machine that conforms to the SAE J2788 standard, you will recover 95% of the refrigerant. Testing also indicates that these new machines' more powerful compressors draw down to far deeper vacuums.

If you are using any older recovery/recycling machine to evacuate the A/C system, it may only recover 50% of the refrigerant, while newer machines recover 95%.

7. Improperly Flushing the System

When any mechanical component of the system has a catastrophic failure, debris may spread throughout the refrigerant loop. Flushing to remove debris that could cause failure of the replacement compressor and to remove debris that could impede refrigerant flow through the condenser is only natural. But flush with the wrong product or use the wrong procedure and you could do more harm than good.

Once again, this is the time to follow the manufacturer's recommendations, which can vary considerably. For example, General Motors recommends flushing with liquid refrigerant, while Ford recommends a liquid flushing solvent. Both manufacturers also recommend using a closed loop flushing machine.

While the flushing agent may be different, flushing with a closed loop flushing machine is the best method for removing all debris from the system.

8. Not Checking for Leaks

Depending on when you make a repair, the owner might not use the system again for months. If a small leak exists, the system might operate well right after repairs, but not months later. Refrigerant escapes easily from small leaks in a damaged system, and it's not always easy to notice the leak. Electronic leak detectors can find leaks effectively and are one of the most efficient ways to check your repairs or deal with a problem leak.

Since the EPA tightly regulates gas release and can fine violators heavily, performing a proper leak inspection after making repairs is advisable.

Refrigerant escapes easily from small leaks in a damaged system, and the evidence of the leak isn't always easy to notice. Electronic leak detectors can find leaks efficiently.

Make sure you have the information you need to avoid A/C service mistakes. A subscription to ChiltonPRO, with comprehensive service information and capacity specifications, will give you all the information you need to keep your A/C system in top shape for the warm weather.

A muscle car enthusiast and drag racer, Jim Marotta is a freelance automotive writer with more than 20 years experience in the automotive industry.

Oil Change: What is the best maintenance interval?

Jim Marotta — Wed, 16 Feb 2011 23:05:00 GMT

By Jim Marotta

The 3,000 mile oil and filter change is as much a part of the American car culture as hot rods, car hops and whitewall tires. Whether we perform it ourselves in the driveway or watch while the family “mechanic” puts the car up on the lift and drains the oil, we think of the 3,000 mile number as the standard interval for oil change service. But, look at a current maintenance interval chart; manufacturers are gradually extending service intervals.

What is the best interval for an oil change? Manufacturers are extending service intervals. Photo by Jim Marotta.

The move toward extended service intervals coincides with new oil technologies that allow manufacturers and refiners to create more stable oils that will endure longer service, and a decrease in the frequency of other services such as tune-ups.

Conventional vs. Synthetic

Traditionally, manufacturers made conventional engine oils from a mineral base oil stock derived from crude oil. Synthetic base oil stocks are produced by either highly processing and refining mineral based oil stock, or by chemically engineering synthetic base oil stock. Current additive packages blended into conventional oils allow them to function longer than oils of the past, but it is primarily the synthetic base stocks that allow greatly extended intervals.

Synthetic oil offers many advantages in durability versus conventional petroleum oil and it is all based on the synthetic oil’s superior resistance to heat and oxidation while requiring little or no viscosity index improvements which are the most vulnerable to degradation as oil ages. Synthetic oil is more accurately controlled at the molecular level and therefore can be engineered to resist the forces in an engine that work against oil durability.

How Long Does Engine Oil Last?

Clearly there is a degree of ambiguity about how long motor oil actually lasts. Traditionally vehicle owners have felt more comfortable with convenient mileage or time-based schedules while others prefer seasonal changes, but the question still remains – how long does engine oil last?

Many factors contribute to the degradation of motor oil. Extreme heat breaks down oil molecules which evaporate and leave deposits on internal engine surfaces, inhibiting the transfer of engine heat to the oil. Oxidation, which is accelerated by heat, further inhibits heat transfer. Environmental contaminants such as dust and dirt enter the engine through improperly maintained filters, and normal engine wear produces metallic particles that travel through the engine increasing wear. Byproducts of normal combustion – soot, dirt, and sludge – contaminate the oil and change viscosity. Finally, internal pressure breaks down the oil film between moving parts which agitate the oil, trapping and suspending air and promoting oxidation.

Lubricant manufacturers continually research and experiment with various chemical additives that in some cases comprise 20 percent of a typical multi-grade oil. In addition to viscosity index improvements, which are the primary additives that allow for multi-grade oils, manufacturers use rust and corrosion inhibitors to neutralize acidic oxidation of the oil. Manufacturers use detergents and dispersants to minimize sludge buildup, along with anti-foaming agents and pressure additives to prevent oil barrier breakdown between internal engine parts. This is known as the shear factor. Manufacturers use additives to aid the base oil in the protection of engine components, but each has limitations and can be affected by the same factors that degrade base oils.

Chemical additives can comprise 20 percent of a typical multi-grade oil. Photo by Jim Marotta.

How Do I Know When My Oil Needs To Be Changed?

One solution presented by the automobile manufacturers is an oil life monitor. Several types of systems exist that use technology to directly “read” the oil. The most popular of these systems rely on capacitance. Using two conducting plates separated by the oil, which acts as an insulating fluid, the system calculates a base capacitance number. As the oil degrades, the system measures the change in capacitance.

Other systems use algorithms to predict oil change intervals.The algorithms are based primarily on factors such as driving habits, driving speed, and failure to replenish low oil levels. Research determined that these factors contribute to oil breakdown. The algorithm method systems also monitor time between oil changes, vehicle speed, coolant temperature, load signal, engine rpm, engine oil temperature and engine oil level to determine the remaining time and mileage before the next oil change. General Motors' Oil Life System and Chrysler Corporation’s Flexible Service System (FSS) are good examples of this type of system.

General Motors’ Oil Life System is based on algorithms that attempt to predict oil change intervals. Photo courtesy of GM.

Goodbye Dipstick?

A new multifunctional system determines oil level and oil condition. The system determines viscosity using a piezoelectric listening device. When this sensitive surface comes into contact with the oil, the oscillation frequency and damping change according to the oil’s mechanical properties, allowing viscosity to be measured. The addition of oil level sensing capability may allow vehicle manufacturers to remove the oil dipstick from the engine.

So, the best answer to our question of how long engine oil lasts is, “it all depends.” Follow the manufacturer’s fluid specifications and maintenance intervals when servicing your vehicle. Get them at www.ChiltonDIY.com or www.ChiltonPRO.com, where a valuable subscription to comprehensive service procedures, specifications, and wiring diagrams, gives you all the information to do the job right.

A muscle car enthusiast and drag racer, Jim Marotta is a freelance automotive writer with more than 20 years experience in the automotive industry.

Cylinder Head Gaskets - Sealing Under Pressure

Jim Marotta — Tue, 21 Dec 2010 18:14:00 GMT

By Jim Marotta

A head gasket's job is to seal combustion gases within the combustion chamber and to prevent coolant and oil from escaping the engine at the head-to-block joint. These requirements have not changed over the years, but the engine operating environment has. Increased cylinder pressures and temperatures, the use of dissimilar block and head materials, and the trend toward lighter-weight engine castings and reduced head clamp loads result in operating conditions that cause much higher levels of horizontal and vertical motion between the head and block.

After only a few thousand miles of operation the finishes and flatness of engine surfaces are no longer virgin castings: the engine has the engine has heated and cooled repeatedly, making the job of sealing much more difficult.

Another challenge facing modern-day head gaskets is zero tolerance for even minor combustion or fluid leaks, primarily due to emissions requirements. Today's head gaskets have to provide a perfect, lock-tight seal in spite of ever increasing pressures, temperatures and other dynamic forces.

Evolving Head Gasket Technology

The original head gasket technology is known as a sandwich-style gasket. Sandwich gaskets combine metal-faced materials with a filler material in between. Since engines of the day were low horsepower and low compression, these gaskets sealed engines adequately into the late 1950s.

As engines grew bigger and more powerful in the early 1960s, some manufacturers started using embossed steel shim-style gaskets. While the steel shim gaskets were even lower tech than their predecessors, they led the way to today's multi-layer steel head gaskets.

The later '60s saw the rise of a new type of composite gasket featuring a perforated steel core with a composite face material applied to each side. These were the first head gaskets that didn't need a secondary (spray-on or brush-on) coating to create a micro-seal between cylinder head and block, or re-torquing.

As engine technology progressed, conventional composite-style head gaskets couldn't withstand the increased casting motion in the new smaller, lighter, and more powerful engines. Lateral motion between the aluminum head and iron block was destroying the facing material through a shearing action, and the vertical motion - in which the head was actually moving away from the block - was over-compressing the gasket.

During the late 1970s and early 80s gaskets contained expanded graphite facing material mechanically clinched to a steel core, offering excellent conformability to surface finish variations. The natural lubricity of expanded graphite accommodated some casting motion, which occurred frequently in the early days of bi-metallic engines.

In the early 1990s, manufacturers introduced Multi-Layer Steel (MLS) head gaskets. Engines using these gaskets featured higher combustion temperatures and pressures, lighter-weight castings, and reduced head-to-block torque loads to prevent bore distortion and combustion blow-by.

An MLS gasket is composed of stacked and embossed multiple layers of full-hard stainless steel, which allow it to act as a "spring" between the head and block to maintain sealing stress against the castings. MLS technology is now the industry standard.

Diagnosing Cylinder Head Gasket Leaks

When a leak occurs externally it is easy to diagnose, as you will see the coolant, oil or carbon soot. But what if no external leak turns up? It is time to check for an internal one.

Dye Tests

The first and easiest check is a dye test. Use a special tool that looks like a turkey baster, to draw air from the top of the radiator. The air passes through a dye that changes color if exhaust gases are present. This is usually a reliable test, as long as the dye is fresh.

Alternatively, use an exhaust analyzer to sniff the same air. Be careful to not allow any coolant to enter your exhaust analyzer.

Cylinder Leak-Down Test

The most accurate test is the cylinder leak-down test. Bring each cylinder to TDC (top dead center) and pump compressed air into the cylinder via a leak-down tool while observing the coolant level in the radiator. When you pressurize the offending cylinder, it's hard to miss the reaction of the coolant.

The most accurate way to test for cylinder head gasket failure is with a cylinder leak down tester.

If there is no reaction in the radiator, remove the pressure, turn the engine until the next cylinder in the firing order is at TDC, and perform the leak-down test again. This test will diagnose failures that involve the coolant passages, but what about failure between cylinders?

An engine with compression leakage between cylinders will run poorly, yet some will continue to drive their vehicles, resulting in a very expensive engine repair. Aluminum cylinder heads have little tolerance for hot gases and extreme pressures: just a few miles of driving will ruin a casting and the cylinder block.

Once again, connect a leak-down tester, and bring the cylinder to TDC. Adjust the regulator for 100 psi going into the cylinder and read the second gauge showing the pressure held in the cylinder. Two adjacent cylinders that show abnormally high leakage will tell you where your potential leak is.

As a final set of checks be certain that:

The engine is in a proper state of tune,
The turbocharger control is functioning properly,
The EGR ports are clear and the system functions properly,
The cooling system is functioning properly, and
Exhaust backpressure is within limits.

All of these checks are to ensure that cylinder temperature and pressure are not abnormally high.

Why Do Head Gaskets Fail?

Today's OEM (original equipment manufacturer) design standard is 100,000-miles-plus durability, which requires improved manufacturing techniques, better quality control, and closer assembly tolerances to rack up the miles without incident.

Prior to the advent of engine controls, detonation and pre-ignition were frequent causes of head gasket failure. While these issues still arise, they are less common since head gaskets are capable of withstanding much higher combustion pressures and temperatures.

When a head gasket fails, investigate to determine the cause of the failure. Remove the old head gasket and measure the bore diameter from the intake side to the exhaust side of the gasket. If the gasket bore has grown .010" over standard, there's a good chance the engine has seen some detonation. Burning and carbon tracking can also be a good indicator of detonation.

Burning and carbon tracking on this cylinder head may indicate detonation.

Burning and carbon tracking from the cylinder head gasket side.

A damaged sealing ring on a gasket from an engine in which the cylinder head torque was not maintained.

You can gain a great deal of information from the witness marks on the face of the gasket and the corresponding deck surface. These marks are a direct reflection of surface finish. Read them carefully before installing a new gasket. The correct surface finish on the heads and block is critical to a good seal.

Replacing Gaskets

When replacing gaskets, pay special attention to head bolts and block preparation:

Be sure to clean and chase threads. (There is a difference between a tap and a thread chaser: Using a tap to chase the threads on your cylinder block will actually cut new threads instead of cleaning them.)
Lubricate bolts (and washers, if applicable) and the underside of bolt heads.
When it comes to torquing the bolts, always follow the OEM-recommend torque sequence and torque specifications to achieve the correct clamp load.
Most importantly, have your torque wrenches calibrated regularly. Since torque specifications are so important, an uncalibrated torque wrench could leave cylinder head bolts too loose or could possibly overtighten and break them.

Always use the OEM-recommended torque sequence and specifications when replacing a cylinder head gasket. Tap into your data 24/7 at: www.ChiltonPRO.com or www.ChiltonDIY.com.

A muscle car enthusiast and drag racer, Jim Marotta is a freelance automotive writer with more than 20 years experience in the automotive industry.

Ford and Lincoln 4-Wheel Air Suspension

Jim Marotta — Thu, 11 Nov 2010 02:26:00 GMT

By Jim Marotta

History

Ford introduced 4-Wheel Air Suspension (4WAS) on the 1995 Explorer, and has since made it available on all three generations of the Ford Expedition and Lincoln Navigator. These big trucks weigh about three tons, so they already have a relatively comfortable ride using conventional suspension. Air suspension smooths that ride even further, but it's also used to increase off-road ride height and for load-leveling, which enhances stability when towing.

Today, air suspension still costs more than conventional suspension, but thanks to modern materials and electronics, it is simpler, reliable and offers more than just a comfortable ride.

Operation

The 4WAS is basically the same as conventional suspension. Up front, air struts replace the standard strut assemblies. In the rear, air springs replace the standard suspension's coil springs. All four air units have a normally-closed solenoid valve operated by the control module for adding or venting air pressure. Changing pressure not only changes ride height, it also changes spring rate. You can replace the solenoid valves on the rear air springs, but not the valves on the front air shocks.

The air suspension system consists of front air struts (center) and rear air springs (left) with shock absorbers (right).

The electric air compressor is different from the compressor on the Rear Air Suspension (RAS) system. It includes a built-in vent solenoid valve and a replaceable air dryer. The solenoid valve is also a spring-loaded safety valve that opens at 260 psi. A solid-state relay mounted below the headlight supplies battery voltage to the compressor.

In addition to the compressor's vent solenoid and the solenoid valve on each suspension unit, there are four more solenoid valves in the system. The front fill solenoid isolates the front air shocks from the rest of the system, and the rear-fill solenoid isolates the rear air springs. The front gate solenoid isolates the front air shocks from each other so the pressure between them does not equalize as the vehicle rolls in a turn. On smooth roads, this valve opens for a softer ride. Lastly, there is a pressure relief valve mounted on the frame crossmember near the rear height sensor. The control unit can use it to vent the rear air springs without having to open the rear-fill and system-vent solenoids.

On 2006 and earlier models, there are two linear ride height sensors that have a total stroke of about 3 inches. Sensor output is 0.25 volts at full extension and 4.75 volts at full compression.

On 2006 and earlier models, there are two linear ride height sensors, one mounted between the rear suspension panhard rod and the crossmember just forward of the spare tire, and one between the frame and the left front upper control arm. Even with only two sensors, the control unit is still capable of limited left/right height adjustments. The sensors have a total stroke of about 3 inches, which is how far the panhard rod and control arm move though the full 10 inches of suspension travel. Sensor output is 0.25 volts at full extension and 4.75 volts at full compression. Adjusting the sensor or the static ride height of the truck requires a scan tool for storing the new settings in the 4WAS control unit.

Later models have four identical potentiometer-type sensors, one at each corner, but they're permanently mounted to left- and right-side brackets so they can't be interchanged. The bracket is bolted to the frame, and a small ball stud link connects the sensor arm to the suspension arm.

On earlier models use the same control unit for the 4WAS, the Rear Air Suspension (RAS) system and the EVO Steering Control Module. Mounted in the instrument panel above the radio, it supplies reference voltage to the height sensors and controls the ground circuit of the compressor relay and the power circuit of each solenoid valve. Inputs come either directly from sensors or from other modules, including the front Generic Control Module (GEM) and the PCM. Inputs include vehicle height, vehicle speed, steering wheel position, brake and accelerator pedal positions, transfer case gear selection, transmission gear selection and door ajar signals.

On later models the Vehicle Dynamics Module (VDM; mounted above the parking brake handle) controls air suspension.

A manual air suspension switch turns the system off for service or long-term storage. On 1997-02 models, the switch is behind the front passenger side kick panel. On newer models, it's behind an access panel aft of the third-row seat on the driver side. That switch controls power to the control unit. When the switch is OFF, a warning light appears on the instrument panel with the ignition switch ON.

All of the air lines in the system are nylon. Two lines connect directly to the drier mounted on the compressor, one leading to the front fill solenoid valve and the other to the rear fill valve. The system uses quick-connect fittings throughout. You cannot repair or splice the air lines.

When the ignition switch is first turned ON, the control module runs a self-diagnostic test, storing or displaying any electrical or electronic problems detected as B or C codes.Any time a door or the rear hatch opens, the system will remember the height sensor readings. If you add or remove weight, the system will operate as needed to maintain that height. Once the doors are all closed and vehicle speed exceeds 10 mph, ride height will readjust as needed. The system's first priority is load leveling, but that's not all it can do.

The control unit can select from three different programmed suspension heights. "Trim" height is the normal ride height for paved road. Defined as trim plus 1 inch, "off-road" height engages automatically when the ignition switch is ON, the transfer case is in 4X4 LOW and the vehicle speed is less than 25 mph. Defined as trim minus 1 inch, "kneel" engages when vehicle speed is zero, all doors are closed and the ignition switch is OFF. Obviously the kneel height is to ease vehicle entry, and while one inch doesn't seem like much, it can make a difference. If the system detects a malfunction, the system will default to trim height, either by operating the compressor or by venting pressure as needed.

Servicing

As noted earlier, there is a switch to turn the system off for service. It should be turned off whenever you lift the wheels off the ground. Failure to do so can cause expensive damage, especially to the rear air springs. The only service required by the 4WAS itself is a visual inspection. Look for physical damage to the air springs, cut or crimped air lines or evidence of something rubbing the lines. There is no pressure sensor in this system, so the self-diagnostic test can't detect a leak. Symptoms of a leak include excessive compressor operation, failure to reach or maintain commanded height, and most commonly, a sagging rear end.

Leaking, dry-rotted air bags will cause excessive compressor operation, failure to reach or maintain commanded height, and most commonly, a sagging suspension.

A quick visual check for physical damage, like this torn airbag can make quick work of diagnosis.

Use soapy water to leak-check the fittings, and check the whole system with a smoke machine. Smoke is especially handy for finding a solenoid valve that's open when it shouldn't be, and vice-versa. Do not, under any circumstances, disconnect any fittings without venting the system first.

Check height sensors for damage and to make sure they're securely mounted. With the vehicle at trim height, sensor output should be 2.66 volts. Repairing, adjusting or replacing a sensor requires a scan tool to recalibrate the system.

Historically the most troublesome part of the system is the compressor. Failures tend to be gradual rather than catastrophic, and tell-tales signs are noise, rough running and excessive current draw. The sagging rear end noted earlier is what commonly drives owners to seek help. When replacing a compressor, techs often replace the solid-state relay too.

After replacing a sensor or the control unit, calibrate the control unit. This involves setting the mechanical ride height (with the system vented), and then using a scan tool to command specific functions through the control unit. The Ford NGS and the new IDS tools are best for the job, but there are some purpose-built aftermarket tools available from companies that sell air suspension parts.

This brings us to the final point. Since the compressor is the part that fails most often, techs often just install a new part and "get lucky." However if something else is wrong, the lack of proper tools, equipment, information, and parts can turn a potentially profitable job into an ugly situation. Should you decide to make the investment, there are several companies that offer everything you need to become an air suspension specialist.

While compressors (shown) are the part that fails the most frequently, a thorough diagnosis can save you money on replacing parts in the long run.

When you need to maintain or service a vehicle, get a valuable subscription to Chilton’s comprehensive service procedures, specifications, technical service bulletins, graphics, and wiring diagrams at www.ChiltonDIY.com or www.ChiltonPRO.com. A subscription, designed for professional technicians and for do-it-yourselfers, can save you many hours of frustration and pay for itself as soon as you use it.

A muscle car enthusiast and drag racer, Jim Marotta is a freelance automotive writer with more than 20 years experience in the automotive industry.

Which Antifreeze is Right for Your Vehicle?

Jim Marotta — Thu, 29 Jul 2010 20:00:00 GMT

By Jim Marotta

Back in the day, no matter which brand you chose, antifreeze was green. The glycol-based formula contained silicates as corrosion inhibitors. You mixed the antifreeze 50/50 with water and poured it in the radiator. As the engine operated, the antifreeze performed its primary duties of carrying heat to the radiator, preventing freezing (hence the name) and protecting against corrosion in the cooling system. You simply changed the antifreeze at the prescribed service interval.

Today, with three types of antifreeze technology in a rainbow of colors, confusion abounds among automotive people and consumers alike as to what color antifreeze is best. The easy part is that most antifreeze manufacturers still make coolant with ethylene glycol (EG), a type of alcohol made from ethane. Manufacturers also make more environmentally friendly versions with less-toxic propylene glycol (PG), a similar compound made from propane.

Evolving Antifreeze

Inorganic Acid Technology (IAT) is the chemical basis for the traditional green antifreeze. IAT contains either EG or PG and is usually fortified with silicate or phosphate additives to make it compatible with metal cooling system components. The generally recommended replacement interval is every three years or 36,000 miles. The owner's manual or maintenance chart from ChiltonPRO.com and ChiltonDIY.com shows what the vehicle manufacturer recommends for each specific vehicle.

Inorganic acid technology is the chemical composition for the traditional green or yellow antifreeze (right). Organic acid technology is the orange coolant on the left.

Organic Acid Technology (OAT) is a Long Life Coolant (LLC) / Extended Life Coolant (ELC) widely used in Europe before its introduction in North America. OAT is usually EG. The generally recommended replacement interval is five years or 150,000 miles; find out what the vehicle manufacturer's recommendations are for your car or truck.

An example of an organic acid technology long life/extended life coolant.

Hybrid Organic Acid Technology (HOAT) combines IAT and OAT with nitrites. Antifreeze manufacturers often refer to it as "global," indicating on the bottle that it meets or exceeds the specification "G-05" for most vehicles newer than 2002 and "G-11" or "G-12" for Volkswagen and Audi. The generally recommended replacement interval is five years or 150,000 miles, always check your vehicle manufacturer's recommendations for your car or truck.

Why All the Different Coolant Formulations?

In the early 1980's Ford was working with antifreeze manufacturers to come up with a formulation to meet global needs. European countries had very hard water and since water is 50% of the antifreeze mix, water quality dramatically affects the overall mix. As European manufacturers were abandoning phosphate-based technology because phosphates tend to form scale, Japanese manufacturers were moving away from silicates, which tend to destroy water pump seals.

The first alternate coolants were hybrids combining carboxyl and silicate technologies. Ford started using them after extensive durability testing (more than 40 million fleet test miles on every vehicle platform that Ford had) in the early 1980s. At about the same time, Mercedes and VW were also using hybrid formulations.

In addition to better corrosion inhibitors for the global market, other issues precipitated formula change. Toxicity and environmental concerns are behind the use of PG rather than EG, while the promise of longer-lasting engine protection and less maintenance spur development of the newest formulations, such as Nissan's new blue coolant, which is designed to last ten years or 135,000 miles.

Does Antifreeze Break Down?

Engine antifreeze does break down, forming corrosive organic degradation products. Antifreeze buffering agents inhibit this corrosion. Since most antifreeze leaks out of the vehicle (according to the EPA, only 12% of antifreeze produced in the U.S. is recycled), most systems are "topped off" with fresh antifreeze, extending its life somewhat. How much depends on the type of antifreeze added.

Can You Mix Antifreeze Technologies?

The one universal coolant that all agree on is water. For best performance, water needs a little help. What happens when antifreezes are mixed? A lot of the confusion about mixing coolants stems from early work with carboxyl coolants. In an American Society of Testing and Materials (ASTM) test, mixing IAT and OAT coolants resulted in more corrosion than either antifreeze alone. Subsequent tests revealed a testing error: the corrosive environment occurred because the coolant was too dilute.

It is best to use the same type of coolant originally used in your car or truck, or the vehicle manufacturer's current recommendations. According to industry experts, if you do not know what coolant is in the vehicle and you top off with another brand, nothing bad is going to happen. Only when dilution rates border 50% is the effectiveness of each coolant's inhibitor package compromised. However, when mixing coolants, the recommended coolant change interval will degrade to that of the shorter-life coolant.

Proper Maintenance is Key

As with anything automotive, proper maintenance is the key to longevity. More important than the type of antifreeze you use is to maintain the cooling system properly by maintaining freeze point protection and proper coolant level. Almost all coolants work best at the ideal freeze point mixture, which for most parts of the country means a 50/50 antifreeze-to-water mixture. At this level, antifreeze protects to -34°F and boil-over protection to 257°F. In addition, maintaining proper freeze point protection ensures corrosion inhibitors are present at intended levels.

Maintaining the cooling system properly by maintaining freeze point protection and proper coolant level is critical. Here a handy tool provides coolant concentrations.

Vehicle manufacturers design cooling systems to operate full of antifreeze. A system that is constantly low on coolant can create an extremely corrosive environment due to the aggressive nature of the vapors of a glycol/water mix. These steam vapors are more corrosive than either fluid by itself. To check your coolant system capacity, simply refer to your vehicle's capacities chart at ChiltonDIY.com, ChiltonPRO.com, or your owner's manual.

If you choose to maintain your cooling system yourself, keep in mind that all types of antifreeze are poisonous. Animals and humans can be attracted by its sweet taste. Used coolant is extremely toxic and an environmental hazard, always recycle it properly.

Tap Water Won't Do

In almost every part of the country, tap water contains minerals such as magnesium and calcium that can form deposits in a cooling system, especially on the engine's hottest parts. The water you use to mix the antifreeze is critical. Premixed coolants are mixed at the factory with distilled water. Use distilled water, not tap or filtered water, when you refill any cooling system.

A system that is constantly low on coolant can create an extremely corrosive engine environment.

Coolant Keeps Working After the Engine Quits

Having the proper coolant level is still important after shutting off the engine. As the coolant stops flowing and the engine temperature increases dramatically, areas of localized boiling can send large shock waves through the engine wreaking havoc on components, especially those made of aluminum.

A subscription to ChiltonDIY or ChiltonPRO, with comprehensive maintenance charts and fluid capacity specifications, will give you all the information you need to keep your cooling system in top shape this summer.

A muscle car enthusiast and drag racer, Jim Marotta is a freelance automotive writer with more than 20 years experience in the automotive industry.

Maintaining and Inspecting Your Automotive Lift

Jim Marotta — Fri, 16 Jul 2010 02:50:00 GMT

Fourth in a Series of Occasional Posts on Shop Maintenance

Photography and Story by Jim Marotta

Whether you use the in-ground or above-ground variety, a lift is one of the most important pieces of equipment in your shop and should be foremost on your inspection and maintenance list. Not only do malfunctioning lifts pose a safety concern, but it's difficult to perform your work without one.

Weight Capacity

Every type of lift requires specific safety procedures for safely lifting vehicles.

The most common type of vehicle lift is the two-post, above ground style. Weight capacity on these lifts can range from 7000 lbs. and higher, so consider the total lift capacity as well as the individual arm capacity (total capacity of the lift divided by the four swing arms) so you will not overload an arm.

Let us say a contractor's pickup truck is in the bay for an oil change. Our 10,000 lbs. lift (each arm lifting up to 2500 lbs.) can easily lift the 1-ton truck into the air. However, the truck's toolboxes and ladder racks make the rear of the truck heavier than the front. If the truck and tools have a total weight of approximately 9000 lbs. and the front/rear weight distribution on the truck is approximately 30/70 (3000 lbs. front and 6000 lbs. rear), we could overload the lift's rear arms and cause the lift to fail.

To ensure safety, manufacturers offer scales on lifts. The scales alert operators to overloaded lift conditions and avoid situations like the rear-heavy work truck scenario.

Proper Lifting

Once we know our lift can handle the vehicle we are lifting, we need to determine proper lifting points. A two-post lift engages the vehicle's frame or lifting points, so it is critical to know the specific lifting points for every vehicle.

Lifting a vehicle at the wrong points can damage components under the vehicle, such as brake lines, suspension components, or body parts. Failure to use the vehicle manufacturer recommended lifting points might cause the vehicle to slip off the lift, resulting in severe vehicle damage and personal injury.

It's critical to know the specific lifting points for every vehicle as specified by the manufacturer. (Photo: Jim Marotta)

As the vehicle's weight comes to rest on the lift arms, a mechanical safety lock system bears the weight of the vehicle at rest, rather than the hydraulic pressure of the lift pistons.

A mechanical safety lock system bears the weight of the vehicle at rest rather than the hydraulic pressure of the lift pistons. (Photo: Jim Marotta)

Maintenance and Inspection

Why is maintenance so important? What shop can afford to have jobs stacked up in the parking lot and employees standing idle? More importantly, you want to ensure the safety of anyone underneath or near your lifts.

How often should you inspect your lift? According to the Automotive Lift Institute (ALI), an association of automotive lift manufacturers promoting the safe design, construction, installation, service, and use of automotive lifts, an automotive lift should receive comprehensive annual inspections, or more frequently when specified by the manufacturer. In addition, ALI lists critical items to inspect every day:

Make sure the operating procedures, safety tips and generic safety material are accessible and legible.
Check for proper operation of the lift controls, restraints and locking devices.
Look for deformation or excessive wear of any of the lift structural components.
Inspect for deformation or excessive wear of other components such as hoses, electrical wires, drive chains, cables, or screws.

By keeping the lift components well lubricated, you can prevent excessive wear. Lubricate the lift cables with an all-purpose silicone lubricant. (Photo: Jim Marotta)

Look for damage or excessive wear on any of the lift contact points, which engage the vehicle during lifting.

The lift pads are where the rubber meets the vehicle. Prevent vehicle damage by replacing cracked or worn pads. (Photo: Jim Marotta)

Inspect for evidence of hydraulic or pneumatic leaks.

Oil seepage past the seals and down the hydraulic pistons is a good sign of a leak. (Photo: Jim Marotta)

Check for unusual noises, sudden movements, erratic operation or evidence of chips or filings during use.
Visually inspect for cracks or loose concrete around floor anchor bolts.

Follow the lift manufacturer's specified inspection and maintenance schedule and in addition, the ALI recommends these periodic inspections:

Confirm there is enough clearance around the lift.
Check all fastening devices for tightness, including the floor anchor bolts.
On lifts equipped with lateral synchronization or equalization systems, check the operation of the systems.
Operate the lift and check the operation of the positive stop and the lift locks.
On lifts with pumping units, confirm there is sufficient oil when the lift is fully raised.

Keeping the pump oil at the proper level is vital to smooth lift operation. Always check the level with the lift fully raised. (Photo: Jim Marotta)

With the lift loaded, stop the load at the midpoint of travel and observe that the load is being properly carried and that the lift does not change position.
With a representative vehicle on the lift, check the lowering speed.

By properly and consistently maintaining your equipment, and properly mounting vehicles on the lift, you will be taking care of one of your most important tools and paying yourself back many times over.

For more information on lifting points, just turn to www.ChiltonPRO.com. A subscription to Chilton's comprehensive service procedures, specifications, and wiring diagrams, gives you the information to do the job right the first time.

A muscle car enthusiast and drag racer, Jim Marotta is a freelance automotive writer with more than 20 years experience in the automotive industry.

How Hybrids Sip Gas, Save Money and Sweeten the Air

David Koontz — Wed, 16 Jun 2010 00:08:00 GMT

By David Koontz

A smug 2009 Toyota Prius, preens and greens in the desert.

More than one million hybrid vehicles quietly navigate America’s roads now, energizing proponents of this technology. Their popularity is no longer in question. Increasingly technicians see them in service bays, car enthusiasts learn how they work, and ecologically-conscious, if not economically-concerned drivers, wish they owned them. There is even unified government, industry and union support for the technology.

From the sweet air of the White House Rose Garden on May 19th, President Obama announced a deal brokered with the auto industry, United AutoWorkers union, the State of California (and other states that want to adopt more stringent standards), that would limit greenhouse gas emissions. The agreement would effectively reduce America’s oil consumption by 5% per year from 2011 to 2016, and increase the average fuel economy of new vehicles sold in America to 35.5 miles per gallon (mpg) by 2016. $50 billion in federal loans will entice automakers to meet that goal over the next seven years.

The current corporate average fuel economy (CAFE) stands at 25 mpg, so we have a lot of work to do to gain those additional 10.5 mpg. It will be met with a variety of technologies and consumer choices, including gasoline-electric hybrids, plug-in hybrids, diesel engine variants, engines that breathe better through more valves, superchargers, or turbochargers, vehicle downsizing, improved aerodynamics and weight-saving techniques.

A 2010 Honda Insight smiles at the road ahead.

Let’s look at how hybrids sip less fuel while belching fewer pollutants. Basically hybrids use battery power to augment gasoline engine power to propel the vehicle. When the vehicle is stopped in traffic, the gasoline engine is shut off. On full hybrids such as the Toyota Prius or Honda Insight, the battery propels the car until it reaches a certain speed or the driver stomps on the accelerator. As more speed is demanded, the gasoline engine restarts and both power sources propel the car. On a mild hybrid such as the Chevrolet Silverado or Saturn Vue, the gasoline engine is shut off when the vehicle is stopped, but it restarts as soon as the driver presses the accelerator. During hard acceleration, a combination starter/alternator provides additional electronic power.

Full hybrid technology usually adds about 10% to the vehicle’s price, while a mild hybrid adds a little less. So, is a hybrid vehicle worth the price differential with a similar sized, gasoline-engine vehicle? That depends on several variables: how much, how long and where you drive; the price of gasoline; insurance price differences; and whether you’ll need to replace the battery during your ownership of the vehicle. A mild hybrid increases fuel economy a modest 10-15% compared to a standard gasoline engine vehicle. But a full hybrid increases mpg by 25-30% compared to a similar-sized vehicle.

Gasoline in my neighborhood costs about $2.85 for a major-branded, standard 87-octane brew. A year ago the same fuel cost about $4.25. Most economists say gas will not get much cheaper and will likely cost more in the future. So, if we predict that the average price of gasoline will increase 10% per year, our sample hybrid vehicle yields 38 mpg while a similar gasoline engine version gets 29 mpg (about 30% more efficient), and we drive 15,000 miles per year, it would take about six years to pay back a vehicle price differential of about $2,500. That example considers fuel savings alone. Consider also that the 2009 federal tax incentive for purchasing certain hybrid vehicles can save you from $1,950 for a four-wheel drive Ford Escape or Mercury Mariner, for example, to $3,000 for two-wheel drive versions of the same vehicles. Now you could get your investment back in as little as one or two years.

This 2007 Ford Escape Hybrid has paid for its price premium already.

Are hybrid vehicles as reliable as standard gasoline engine models? In short, yes. Most vehicle manufacturers offer extended vehicle warranties to cover repairs and, other than the early Saturn Vues, hybrids have been very reliable. While most batteries are safely tucked behind panels on hybrid vehicles, we recommend following precautions such as these when working with the high-voltage battery and electrical circuits. As with any vehicle, when you need to maintain or service them, click on www.ChiltonDIY.com or www.ChiltonPRO.com to obtain a valuable subscription to Chilton’s comprehensive service procedures, specifications, graphics and wiring diagrams. These subscriptions, designed respectively for do-it-yourselfers and professional technicians, can save you many hours of frustration and pay for themselves as soon as they are used.

Now those are truly sweet deals.

David Koontz is the publisher of Chilton. He enjoys writing in all genres — from technical to poetry. In addition to a few domestic vehicles, he has owned, repaired and rebuilt some intriguing imported cars from makes such as Alfa Romeo, BMW, Fiat, Jaguar, Merkur, MG and SAAB. David has spent most of his life in southern California and resides there with his wife, Donna.

Kicking the Dirt to the Curb: The Never-Ending Battle to Keep Your Car Clean

Ryan Lee Price — Tue, 08 Jun 2010 17:44:00 GMT

Detailing: Part One

Story and Photography by Ryan Lee Price

Once the water evaporates, what is left are rings of crystals bonded to the paint and crusted with dirt.

The Shiny Side

On the first day, God created sunlight and dirt; four days later, He added bugs and birds. Some time after that, the car came along, and the four have been locked in mortal combat ever since. Like a game of Paper, Scissors, Rock: car kills bug; bug kill paint; bird kills bug; bird poops on car, kills paint (occasionally, car kills bird). It is a vicious cycle, and if you've been on a long drive anywhere out of town, you're familiar with the Technicolor insect necropolis on your windshield as a testimony to the damage it can do to your car's shiny side.

The main enemies of a pristine paint job are acid rain, bird droppings, alkaline-laden water drops (hard water) and plain old-fashioned dirt. Thanks to the industrial revolution, nitrous oxide and sulfur dioxide emissions from power plants, car exhaust and air pollution from industry are now trapped in rain water and dumped on your car during a storm. Called acid rain, it's basically a very dilute form of nitric and sulfuric acids. The sun dries the water droplets containing these acids and they are left behind to concentrate on your car's surface. Soon the concentrated acid penetrates the clear coat, dissolving the resin and forming a microscopic pit. Left untreated, the pit collects moisture and the concentrated acid can continue into the basecoat, destroying the pigment and eventually, the whole car.

Bird droppings contain a byproduct called uric acid. This alkaline, if left non-neutralized, can penetrate the clear-coat and cause damage similar to acid rain. Alkaline watermarks are all too familiar: What amounts to hard water spots are calcium and magnesium salt deposits on the paint after the water has evaporated. These white rings of minute crystals bond to the paint and cannot be re-dissolved by water; only a good degreaser can break up that relationship.

Every car enthusiast should have a cabinet in their garage just like this, with something to handle every car care situation that may arise.

Wash your car regularly. When the car is clean, unwanted moisture will dry up quickly, but when it's dirty, moisture accumulates with the dirt and causes corrosion. Use soap intended for a car's paint, not for washing dishes. You don't eat off of your car and you don't drive your plates, so leave the dishwashing soap in the kitchen. Wash your car in the shade and never in direct sunlight.

Wash the rims first (tires and windows last), and make sure they're cold before applying any rim cleaner. Hot wheels will burn the cleaner onto the rim and cause discoloration and/or permanent damage. Use a good quality cleaner designed for your car's rims. Don't rinse the rims and tires first, so you can apply the cleaner full-strength. Check the service information for special recommendations for your specific vehicle.

Use different a sponge for your tires (and any exterior rubber) and always start at the top of the car and wash down, so you're not dragging dirt over clean panels-plus the closer you get to the street, the dirtier the car is. Use a degreaser on tough areas, like oil spots, salt damage, and bug splatter.

Avoid any product that contains formaldehyde or any harsh preservatives, as they will harm tires.

When the car is mostly dry, apply a good tire dressing to the tires and bumpers. If you do this before you wax the car, and spray the dressing onto a rag, airborne droplets won't mar your freshly washed car. Avoid any product that contains formaldehyde or any harsh preservatives, as they will harm tires.

Instant detailer acts as a wax and gives you a great start toward a glossy shine.

While the car is still wet, mist it with instant detailer and chamois it dry. Instant detailer acts as a wax and gives you a great start toward that glossy shine. Never use a terrycloth towel, unless you love thousands of little scratches caused by dirt trapped in the loop pile. Many stores offer microfiber towels that work perfectly. At this point, the car doesn't have to be 100 percent dry, but just make sure you remove most of the water so it doesn't get a chance to bead up. Take a quick spin down the street and wipe off any water that has been blown from the mirrors, tires, or molding.

The Inside Story

Start by vacuuming the floor, the pockets, cup holders, anywhere that something can fall into (e.g., the glove box). For best results, remove everything from the car, from the floor mats to the coffee coupons in the console. Start with a small brush and get the dust and dirt out of the speaker grills and around the dash joints. To achieve professional results when cleaning carpets, always brush the carpet in one direction. Check the service information for specific recommendations as in this Technical Service Bulletin example from General Motors and Saab. Vehicle manufacturers may also have tips for leather care, check updated service information to learn what's recommended for your year, make and model.

Keep vinyl seats clean with a non-oil-based cleaner and a coarse towel to reach into crevices.

Clean Streaks

Never use a window cleaner that has ammonia, especially if you have a leather dash or trim. Ammonia overspray blocks the pores of the leather so it can't breathe properly, which will fog up your windows and leave streaks. Clean windows horizontally on the outside and vertically on the inside, so if it does streak, you'll know which side.

Now what you're left with is a clean car, complete with protection from the elements. However, like life, the concept of clean is fleeting, so keep this article handy for reference.

Cars that have been recently waxed or those that are somewhat new only need a good one-step cleaner/sealant/wax. If you wax the car often (every two to three months) use a quality carnauba wax or a quality cleaner wax. (Look for the second article of this series on Detailing for tips to achieve an amazing finish for older vehicles.)

Get comprehensive information about most any car on the road with a subscription to www.ChiltonDIY.com. Whatever your skill level, keeping your car clean is almost as important as keeping it running strong. To help reach that goal, keep your Chilton handy; it's especially tailored for you and your vehicle.

Achieving Better Fuel Economy and High Performance with Gasoline Direct Injection

Jim Marotta — Tue, 26 Jan 2010 21:00:00 GMT

By Jim Marotta

Trying to choose between performance and economy is often a very difficult decision, and usually there has to be a compromise between the two. However, one technology is helping to power gasoline engines to new heights of performance, while pushing fuel mileage forward by leaps and bounds: gasoline direct injection. The photos below from Bosch illustrate the key elements of a gasoline direct injection system.

Back in the Day

Direct fuel injection is not a new idea. Diesel engines have always used the technology, which squirts fuel under high pressure into an engine’s cylinders rather than into the intake manifold. In a diesel engine, the process of injecting fuel directly into the combustion chamber at the top of the compression stroke initiates and controls combustion. The Robert Bosch Company perfected the modern mechanical injection pump for small diesels in Germany in 1927.

Bosch developed the first automotive direct injection system using gasoline, and Mercedes introduced it on the 1955 Mercedes Benz 300SL. Engine power was double that of its carbureted counterparts and allowed a top speed of up to 161 mph, making it the fastest production car of its time.

How Direct Injection Works

It might be easiest to see how direct injection works by comparing it to traditional fuel injection methods. With conventional fuel injection, injectors supply all cylinders with a mist mixture of air and fuel, averaging a constant 14.7:1 ratio, known as a stoichiometric mixture. Vacuum draws the mixture into the cylinder where the spark plug ignites it. The throttle valve determines how much of the air/fuel mixture enters each cylinder, keeping the mixture at an optimum 14.7:1 ratio. Lean air/fuel mixtures won’t ignite well, creating excessive NOx and hydrocarbon emissions which the catalytic converter must then capture and process.

In a direct injection engine, the injection nozzle is located inside the combustion chamber and injects a finer spray, like that from an atomizer bottle. Each solenoid-controlled injector has minute outlet holes which exude a fine mist. Injectors positioned to the side of each cylinder, aim the fuel into the cylinder, adjacent to the spark plug, and alongside the intake and exhaust valves.

Like an atomizer bottle spray, the fine mist generated by each solenoid-controlled injector's tiny outlet holes creates a well-atomized air/fuel mixture. Injectors spray fuel into the cylinders at pressures of up to 2,150 psi, about 35 times more intense than port fuel injection. (Courtesy of Bosch.)

A high-pressure fuel rail feeds each bank of cylinders using individual injectors and a fuel rail pressure sensor to help the powertrain control module precisely control fuel pressure. Some systems fire the injectors multiple times during one injection event at pressures of up to 2,150 psi, which is about 35 times more intense than port fuel injection.

Each bank of cylinders has a high-pressure fuel rail that feeds the individual injectors, and a high-pressure pump with a rail pressure sensor that helps the vehicle powertrain control module precisely control fuel pressure. (Courtesy of Bosch.)

When the injectors spray fuel into the cylinder, a relatively small, precisely-shaped volume of ignitable air/fuel mixture surrounds each spark plug. Areas inside the combustion chamber, but away from the spark plug, merely contain air or recirculated exhaust gas. This stratification of the charge allows the engine to burn mixtures with a much higher rate of air than conventional engines. The cushion of non-combustible gas around the combustion chamber also means less combustion heat to evacuate. This improves the thermal efficiency of the engine, increasing fuel economy.

To control injection valves, new common-rail injectors use a rapid-action actuator made of piezo crystals. Piezo package movement is transmitted non-mechanically and without friction to the rapidly switching nozzle needle. This doubles the injector's switching speed, allowing a more precise measurement of fuel injected, and thus reducing harmful combustion by-products. (Courtesy of Bosch.)

Since direct injection charge stratification works best at low and medium loads in the lower half of the engine speed range where traditional gasoline engines are least efficient, it allows direct injection engines to obtain up to 21 percent better fuel economy.

How Working Together Improves Performance and Economy

The future of direct injection involves coupling the system with other technologies, such as turbocharging and automatic engine stopping and restarting. By integrating multiple technologies, automakers can develop smaller, more fuel-efficient engines, while improving performance.

Turbocharging direct injection engines is a promising fuel economy technology. A turbocharged, direct-injection engine combines existing and proven technologies, allowing manufacturers to meet future emission standards using existing catalytic converters. Automakers can apply this technology across a manufacturer’s entire engine portfolio, including flexible fuel applications.

Other technologies maximize direct injection engine thermodynamics. In economy mode, an insulating blanket of air and recirculated exhaust gas helps keep heat away from the cylinder walls and head. In high-powered mode, the engine creates more heat. By controlling the operating speed of the water pump, especially during economy mode operation, a reduction in drag on the engine provides improved fuel economy. Variable intake and exhaust timing is especially efficient with gasoline direct injection and turbocharging systems. The variable engine timing enabled by camshaft phasing can optimize the combustion process. Also, valve overlap at low rpm can be adjusted by the engine controller to increase the turbocharger response, reducing turbo lag.

Servicing

With almost every manufacturer offering at least one direct injection engine, technicians should be seeing these vehicles in their bays for service.

“The biggest item to consider when servicing (direct injection) systems is the high voltage and fuel pressures the systems generate,” says Al Krenz, director of service for Bosch North America. A direct injection system typically will operate between 725 psi up to 2050 psi, so bleeding down the fuel system properly is important.”

“Always follow the manufacturer’s procedure to relieve the fuel system before performing any repairs to the system,” Krenz recommends.

Carefully diagnose the fuel injector voltage signals. High-pressure injectors typically actuate at approximately 70 volts and 10 amps, with the capability to rise over 120 volts.

As with diesel direct injectors, carbon can build up on the injector tip and interfere with fuel distribution and atomization. While typical port injectors produce a fuel droplet of approximately 165 microns, direct injectors atomize a much smaller fuel droplet size of only 65 microns, so even the slightest loss of fuel delivery will adversely affect engine drivability, power output, fuel economy and exhaust emission.

Direct injection and other complementary systems provide performance and economy by using very complex technologies. If you want to learn more about how specific direct injection and other technologies work, become a ChiltonPRO.com subscriber and receive all system service instructions.

A muscle car enthusiast and drag racer, Jim Marotta is a freelance automotive writer with more than 20 years experience in the automotive industry.

Maintaining Your Shop's Computer Equipment

Jim Marotta — Wed, 25 Nov 2009 02:34:00 GMT

Third in a Series of Occasional Posts on Shop Maintenance

Photography and Story by Jim Marotta

A clean temperate climate and a consistent flow of electricity

Where would we be today without our computers? They power our shop management systems, provide our diagnostic and service information and enable us to order parts without picking up the phone. The only thing they require is a clean, temperate climate and a consistent flow of electricity. What most shop owners don't know is that the electrical power supplied from the wall outlet may not be stable enough to power their computers.

Depending on where your shop is located, power line disturbances strong enough to disrupt computer operation can occur frequently, resulting in hardware damage and more importantly, lost data. Unfortunately, equipment like your compressor and brake lathe are electrically "noisy" enough to cause disturbances.

Installing an Uninterruptible Power Supply (UPS) to the power supply for your computer equipment will not only provide backup AC power, allowing an orderly shutdown of computer equipment in the event of a power failure or blackout, but better units will also condition the electricity and allow for an uninterrupted supply of power.

The UPS system (left) used on this shop office computer provides backup AC power in the event of a power failure and conditions the electricity, allowing for a consistent supply of power to the computer. (Photography by Jim Marotta.)

Keep it clean

Shops are dirty, especially for computers. Use a computer vacuum or clean, dry, low pressure shop air monthly to prevent dust from accumulating on the power supplies, fans, heat sinks and vents. A gentle cleaning with appropriate cleaners will keep all surfaces of the computer, keyboard, mouse and screen fresh. Consider covering equipment when not in use.

Computers used on the shop floor require regular maintenance to prevent dust and dirt from accumulating on the power supplies, fans, heat sinks and vents. (Photography by Jim Marotta.)

Update and backup regularly

Now that the outside of the computer is maintained, let's turn our attention to the inside. For security and reliability purposes, update programs regularly. Install large updates, such as Service Packs, only after checking with software vendors to make sure there are no compatibility issues. Update your anti-virus software regularly, as the software is fully protecting the computer only if it is receiving updated virus signatures.

What would happen if you lost your building and all its contents to fire? You may be able to temporarily relocate but how would you contact your customers if all their information was on your (now melted) shop computer? Backup daily and weekly to insure none of your data is lost. Here is how to do it:

Contact all hardware and software vendors for documentation regarding which files to back up.
Perform daily on-site backups of all computers containing shop management and accounting software data files to correct accidental deletion of files, hardware failures, and system crashes.
Perform weekly backups of all computers containing shop management and accounting software data files and keep these discs in a secure place offsite to recover from catastrophic disasters such as fire or flood.
Both Microsoft and Apple provide free built-in backup utilities that are more than capable of satisfying the backup needs of all but the most complex computer systems and networks.

Every day the consequences of neglected maintenance appear on the vehicles that roll or are towed into the shop; the reasons for maintaining your shop equipment are equally clear. Protecting and maintaining our computers includes the simple tasks of keeping it clean and temperature-controlled, giving it an uninterruptible power source, and updating and backing up regularly. When you subscribe to Chilton for your automotive service, repair, and estimating information, Chilton takes care of the updates and backups for you. Just sign on to www.ChiltonPRO.com and www.ChiltonDIY.com, anytime.

A muscle car enthusiast and drag racer, Jim Marotta is a freelance automotive writer with more than 20 years experience in the automotive industry.

What You Need to Know About Tire Pressure Monitoring Systems

Jim Marotta — Wed, 18 Nov 2009 03:08:00 GMT

By Jim Marotta

A Tire Pressure Monitoring System (TPMS) is an electronic system designed to monitor the air pressure inside automotive tires. The system transmits real-time tire pressure information to the driver of the vehicle using a simple low pressure warning light in the instrument cluster.

Luxury becomes necessity

The first passenger vehicle to adopt TPMS was the Porsche 959 in 1986. Due to the increased use of Run Flat Tires, TPMS quickly became optional equipment for many luxury passenger vehicles, such as the Audi A8, Mercedes Benz S Class, BMW 7 Series, and the Chevrolet Corvette.

In the fall of 2000, following several fatal accidents involving underinflated tire failure and vehicle rollover, Congress signed into law the Transportation Recall, Enhancement, Accountability and Documentation Act (TREAD). This law mandates the use of a suitable TPMS technology to alert drivers of a severe underinflation condition of their tires. The law requires that all new vehicles produced for the US market after September 2007 have TPMS.

Direct and indirect TPMS

There are two types of tire pressure monitoring systems on the market today - direct and indirect.

Direct TPMS

Direct TPMS systems employ pressure sensors inside each tire to transmit air pressure information from inside the tire to a receiver and then to illuminate a light on the vehicle's instrument cluster. The system can identify simultaneous underinflation in all four tires in any combination with a typical trigger point of 25% below the recommended cold psi rating.

Direct TPMS systems employ pressure sensors inside each tire to transmit air pressure information from inside the tire to a receiver. (Courtesy of Toyota.)

High-line and low-line direct tire pressure monitors

Two types of direct tire pressure monitors are currently in use: high line and low line. High-line systems use low frequency transmitters near each wheel to force wheel-mounted sensors to transmit air pressure information when the ignition is switched on and then periodically as the vehicle is in motion. The transmitters are activated one at a time in sequence so that the system can determine the location of the wheel with low pressure. Some vehicles use only three transmitters to save money. High-line direct tire pressure systems tend to be used on higher-end models.

Low-line system sensors transmit their own signals. Since two or more sensors on a vehicle may transmit simultaneously, individual systems use different methods to ensure signals are received by the vehicle. On some systems the message is re-transmitted in a random or pseudo random pattern multiple times to reduce the effect of interference on communication. Another method is to simply transmit signals more frequently. When sensors detect a rapid change in pressure or a temperature that is too high, they start to transmit immediately. Low-line systems are used on the majority of vehicles due to their lower cost.

How indirect systems work

Indirect systems do not use physical pressure sensors but rather measure the apparent air pressure, by monitoring individual wheel rotational speeds, and other signals available outside the tire itself. An underinflated tire has a slightly smaller diameter than a correctly inflated tire and therefore has to rotate at a higher velocity to cover the same distance as a correctly inflated tire. The system functions in combination with wheel speed sensors for anti-lock braking systems (ABS), and electronic stability control systems (ESC).

Indirect systems do not use physical pressure sensors but rather measure the apparent air pressure, by monitoring individual wheel rotational speeds (Courtesy of Toyota.)

One disadvantage of indirect TPMS is that the driver must calibrate the system by pushing a reset button on the dashboard or through the onboard computer and if this is performed when any tire is in an underinflated condition the system will not report correctly.

TPMS Evolution

Recently, electronic systems manufacturer Johnson Controls introduced a new TPMS that uses an adaptive auto-learn capability to automatically detect the sensors and determine their positions. The system automatically calculates the positions of each tire sensor, analyzing signal input from the ABS and ESP control unit at the start of a journey. There is no need for a manual learning procedure, even after a tire change.

Techs can calibrate new sets of tires within two to three minutes. The system can also permanently save additional sensor IDs, increasing the calibration speed of a set of winter tires. After the system detects the saved IDs, the sensors calibrate quicker, even if these tires are mounted in different positions than before.

The system reports low pressure just as precisely for one individual tire as for all four tires. The sensor technology can even detect a minimal 1 psi change in pressure. While the system is direct-measuring, it is unlike comparable systems in that it only uses a single antenna which is integrated directly into the TPMS control unit. Because the receiver software calculates all of the information needed to analyze the signals, it requires no other components apart from the tire sensors.

Avoid service mishaps

On direct TPMS systems, any service requiring the dismounting and mounting of tires can damage a sensor unit, including new tire installation and flat repairs. Other common service mishaps include inappropriate tool use, incorrect valve stem sensor installation and torque, and not replacing the nickel-plated valve core and rubber grommet in the valve stem.

Incorrect valve stem sensor installation and torque, and not replacing the nickel-plated valve core and rubber grommet in the valve stem can cause problems with the sensor. (Courtesy of Toyota.)

Another issue that seems to be a common concern is the weather, specifically in the climates of the northern US. The harsh winter weather affects the aluminum sensors causing them to oxidize on the inside.

Any service that requires the dismounting and mounting of tires can damage a sensor unit, including new tire installation. Proper tire machine technique is critical to not damage the sensor. (Courtesy of Toyota.)

Most indirect TPMS systems require resetting to recalibrate the system. A reset is typically required after adding air to a low tire, after changing or servicing a tire, or after rotating the tires on a vehicle. Finding the reset button and determining the reset procedure are the only difficult points to service.

With so many different reset procedures, it's important to make sure you are using the right procedure for the vehicle being serviced. Since GM has over 10 different procedures depending on application, consult www.ChiltonDIY.com or www.ChiltonPRO.com, for the proper procedure and the location of the reset button. You can access Chilton's comprehensive service procedures, specifications, and wiring diagrams online 24/7.

While TPMS systems offer increased safety to drivers through low pressure warnings, they are not meant to be a substitute for proper tire pressure maintenance. How frequently should you be checking tire air pressure? Certainly any time the ambient temperature changes dramatically, and follow the manufacturer's maintenance intervals and specified inflation pressures. Get them at www.ChiltonDIY.com or www.ChiltonPRO.com.

A muscle car enthusiast and drag racer, Jim Marotta is a freelance automotive writer with more than 20 years experience in the automotive industry.

Why You Need to Maintain Your A/C Recovery and Recycling Machine

Jim Marotta — Sun, 15 Nov 2009 03:28:00 GMT

Second in a Series of Occasional Posts on Shop Maintenance

Photography and Story by Jim Marotta

It's a sweltering August afternoon and an overheated customer comes in saying the A/C isn't working. Earlier this week you convinced him to pay for needed A/C system maintenance. What went wrong? Could it be deferred maintenance on your refrigerant recovery and recycling machine? Recovery and recycling machines have come a long way from their simple beginnings. However, with more complexity, there is more to go wrong.

Back to Basics

Surprisingly, basic maintenance on today's complex recycle/recovery machines has not changed that much. You still need to change the filters regularly and change the vacuum pump oil, if the machine has a vacuum pump. Also, you must purge the air from the tank. Draining the refrigerant oil recovery bottle after each use is a required daily maintenance task.

Changing the filters, O-rings, oils, and leak checking the unit can usually be done in about 1 to 1-1/2 hours with the parts costing under $100. Some machines will even prompt you when it is time for maintenance. Even the older machines use an hour meter that indicates usage between maintenance intervals.

When it comes to changing the filters, most are easily changed with common hand tools. Some even have knurled fittings and do not require hand tools at all. Changing vacuum pump oil is just as simple. While each manufacturer has a specified procedure, most are simply a drain and refill. Changing out the oil ensures efficient operation, reducing the amount of time the machine takes to evacuate the system. Another item, keeping a machine clean, is simply a matter of wiping up spilt oil or covering the machine to keep dust out of the electronic circuit boards.

Replacing a typical filter is a matter of loosening the tubing nuts and replacing the filter. Photography by Jim Marotta.

With repair bills for recovery/recycling machines averaging $400 and up, and the cost of a new automatic machine averaging $2500, plus the lost revenue from the absent machine, you can see that maintenance is the answer.

Common problems and failures

Oil drain bottle is not drained after each recovery - If the oil bottle is not drained and allowed to fill up, it will allow liquid refrigerant to enter the compressor. The compressor is made to pump gas and when liquid is allowed to enter the compressor it will damage the valves. The only repair at that point is to replace the compressor.

A twist of the wrist after each service keeps oil from building up and causing damage to the machine. Photography by Jim Marotta.

Air in the refrigerant - When air finds it way into your storage tank it can be troublesome: it can shut the machine off due to excessive pressure and slow down the recovery process. You can tell if air is present by comparing the pressure and temperature in the storage tank to the manufacturer's table. Follow the manufacturer's instructions and purge the air regularly; you don't want air in your customer's A/C system and you don't want it in your recycler.

The machine is left dirty or dusty - Keep it free of dust to protect the circuit boards in the machine. Too much dust can cause the circuit boards to short circuit and fail. Some of the boards are $500 to $800 just for the part.

A buildup of dust on circuit boards may cause them to short circuit and fail. Photography by Jim Marotta.

Dirt drawn in through the compressor air intake will eventually cause accelerated wear on this unit. Photography by Jim Marotta.

Tank valves leak - When you have a tank valve leak it is usually due to overtightening or overopening the valve, which damages the valve seats. The tanks are required to meet DOT certifications and if a valve is replaced in the original tank or if the tank is older than five years send it out to be recertified, just like a welding cylinder. The cost of a new tank is most often less than or about the same cost of replacing the valve and sending it out or recertification. You can get a new tank on the machine a lot quicker.

Excessive force when closing a service valve wears out the valve seat, causing the valve to leak and refrigerant to escape. Photography by Jim Marotta.

Hoses and O-rings leak - Inspect hoses regularly and replace them if they are bad. If working with pressure in the line, the refrigerant will most likely leak out like air through a leaky fitting on a shop air fitting. However if you are working with vacuum in the lines you may experience the symptoms of a compressor or vacuum pump failure. Symptoms include the unit not pulling down adequately. If the machine is in recovery, this will fill your recovery tank with air pressure and eventually should shut the machine down.

Why replace O-rings? Take a look at this comparison. The one on the left is new. The one on the right is swelled and could allow refrigerant to escape or air to enter the system. Photography by Jim Marotta.

The other common problem with O-rings, and this one is much more overlooked, is people tend to overtighten the hose connections especially when the O-rings have deteriorated and are in need of replacement. This causes the O-rings to over-compress and seal off the flow of the hose, resulting in slow or no charging, recovery, and evacuation depending on which hoses are affected.

This is not a reliable seal under pressure or vacuum. Under pressure refrigerant will leak out and under vacuum air will leak in. Photography by Jim Marotta.

Another byproduct of overtightening the O-rings and not replacing them is that small pieces of the O-rings may break apart creating fragments which tend to get stuck in the valve cores and solenoids causing recycler malfunction.

Keypads fail - Keypads will wear out with use, but take care not to use screwdrivers or other items to push the keys.

Scales require calibration - Overcharging or undercharging a system usually results in a comeback and a hot, angry customer. Calibrate the scales frequently.

Save yourself the aggravation of comebacks caused by neglected maintenance of your recovery and recycling machine. Good tools, available when you need them are essential to your professional image and your business. Don't neglect your service information. Subscribe to ChiltonPRO and access the information you need when you need it. For those who only need information on only one or a few models, ChiltonDIY is available.

A muscle car enthusiast and drag racer, Jim Marotta is a freelance automotive writer with more than 20 years experience in the automotive industry.