1. BELT TENSIONERS
Most late-model engines have serpentine belt drives for the engine-driven accessories. And most people know that belts are a maintenance item and eventually have to be replaced. But many don’t know the spring-loaded automatic tensioner that keeps a serpentine belt tight is also a wear item. Consequently, the automatic tensioner may also have to be replaced when the time comes to change the belt.
The automatic tensioner has a coil spring inside that applies just the right amount of force against the belt to keep it tight. The tensioner also provides a little “give” so it can absorb and cushion shock loads on the belt that occur when the A/C compressor clutch cycles on and off. What’s more, the tensioner automatically compensates for wear and keeps the belt under constant tension.
But nothing lasts forever, not belts and not automatic tensioners. The typical service life of a serpentine belt is about 60,000 miles or five years. When the belt nears the end of its life, it may become cracked, glazed and noisy.
If an aging belt is not replaced, it may break, causing a loss of drive torque to all of the engine’s accessories. When the water pump stops turning, the flow of coolant stops and the engine begins to overheat. When the alternator stops turning, there is no charging output and the battery starts to run down. When the power steering pump stops turning, the steering suddenly gets very stiff and hard to control.
All too often, an old serpentine belt (or a broken belt) will be replaced with a new one. But the automatic tensioner is not inspected to make sure it is still working properly and is in good condition. This mistake can lead to rapid belt wear and repeat belt failures if the tensioner is weak or worn out.
Belt tension is critical. Too little tension may allow the belt to slip and squeal. Slippage also causes the belt to run hot and age prematurely. And if the belt is really loose, it may come off its pulleys. Too much tension on a belt may overload it as well as the shaft bearings on the water pump, alternator, power steering pump and air conditioning compressor, possibly leading to premature failures in these components.
Belt tensioners were first used back in the late 1970s. These early units were fixed tensioners that required manual adjustment. Then automatic belt tensioners arrived in the mid-1980s. The spring-loaded design eliminated the need for manual adjustments and assured proper belt tension for the life of the belt. Because of this, the tensioner is often overlooked when a belt is replaced. Even so, the tensioner should always be inspected when changing a belt because:
Rust or corrosion can jam the tensioner housing and prevent it from rotating freely. A frozen tensioner cannot maintain proper belt tension. Corrosion is usually a result of road splash, especially in areas where roads are heavily salted during the winter.
Dirt or mud can also jam the tensioner housing.
A loose or worn pivot arm can allow unwanted movement that results in belt noise and misalignment. Over time, this will increase belt wear and lead to premature belt failure.
A worn bushing in the tensioner pulley can cause vibrations and noise. If the bushing seizes, it may cause the belt to snap.
A weak or broken spring inside the tensioner can’t maintain proper tension and the belt will slip. Springs lose tension over time from exposure to heat.
Cracks or damage to the tensioner housing or pulley arm may prevent it from rotating smoothly and maintaining proper belt tension.
Symptoms that typically indicate an automatic tensioner has reached the end of the road include:
Belt slipping (due to loss of tension).
Belt glazing (caused by slipping).
Excessive movement or rocking of the tensioner pulley or “belt flutter” when the engine is running. This means the spring inside the tensioner is weak and/or the bushing is worn. The tensioner needs to be replaced.
Wobble in the tensioner pulley (or idler pulley). Wobble means the bearings are shot.
Belt or tensioner noise. The tensioner should be quiet when the engine is running. Any squealing, rumbling, growling or chirping noises should be investigated to determine the cause. A mechanic’s stethoscope can be used to pinpoint the source of the noise. The probe should be placed against the bolt in the center of the tensioner pulley wheel to listen for bearing noise. The idler pulley(s) should also be checked because the bearings in this component can wear out, too. The same goes for all the engine-driven accessories (water pump, alternator, PS pump and A/C compressor).
Pulley damage. Physical damage of any kind on the automatic tensioner pulley may indicate excessive tension or physical interference. If the pulley is damaged, replace the tensioner assembly not just the pulley. If an idler pulley is damaged, inspect the tensioner also because vibrations caused by a bad idler pulley may damage the tensioner.
Check the movement of the tensioner arm with the engine off. Use a socket with a long handle ratchet or breaker bar on the tensioner pulley center bolt to rotate the tensioner. There are no specifications for measuring the amount of resistance offered by the tensioner spring, but if the tensioner offers little resistance it may indicate a weak or broken spring. If it fails to move at all, the tensioner is jammed and needs to be replaced.
Watch for looseness in the arm when the tensioner is rotated. The arm should not wobble or twist. If it does, the tensioner bearings are worn and the unit needs to be replaced.
Also note the position of the arm on the automatic tensioner. Many units have marks on the housing that show the normal range in which the arm can pivot. If the position of the arm is outside these marks, it indicates a problem (the belt may be too long or too short, or the tensioner may be jammed).
Note the wear pattern on the tensioner and idler pulley(s). Misalignment and bearing wear can cause the belt to track off-center. This will cause the belt to wear quickly. The tensioner and idler pulley bearings can be checked by removing the belt and spinning the pulleys by hand. All pulleys should turn freely with no binding, roughness or wobble. Any binding, roughness or wobble means these parts are bad and need to be replaced.
Pulley alignment should also be checked to make sure there isn’t a mounting problem in the belt drive system. Pulley alignment can be checked by placing a straight edge against the pulleys, or with a special laser alignment tool designed for this purpose.
If the automatic belt tensioner has failed (and the engine has a lot of miles on it), it’s probably a good idea to replace the idler pulley(s) at the same time. Why? Because the shaft bearings on all the pulleys will have the same amount of wear. If they are reaching the end of their service life, replacing them now will restore the pulleys to like-new condition and reduce the risk of a breakdown because of a belt or pulley failure.
Aftermarket automatic tensioners are often a better replacement choice than an original equipment tensioner, especially on older vehicle applications. Some OEM tensioners (Chrysler 3.0L, 3.3L and 3.8L, for example) were not very robust and have experienced a high failure rate over the years. Rather than simply copy these OEM tensioner designs with their inherent flaws, some aftermarket manufacturers have re-engineered their parts to overcome the weaknesses of the original design. As a result, some aftermarket replacement tensioners may not look exactly the same as the original. But there’s a reason for this these parts have been redesigned to outperform and outlast the original parts they replace.
A special tool that may be needed when replacing a serpentine belt or automatic tensioner on a transverse-mounted engine in a front-wheel drive vehicle is a special serpentine belt removal tool. The tool has a long, flat extension handle that allows a socket to be placed on the tensioner bolt, so the tensioner in a tight engine compartment, can be easily rotated to relive pressure on the belt. Without this tool, the job is nearly impossible on some vehicles.
2. CABIN AIR FILTERS
They call it the “hidden filter” because many motorists don’t realize their vehicles have separate air filters for the passenger compartments. Cabin air filters first appeared back in the mid-1980s. The earliest applications were on Audi and other European makes. Today, about 80 percent of all new import and domestic vehicles have a cabin air filter or a slot where one can be installed.
Cabin air filters are put there for the health of the vehicle’s occupants. The filter can trap pollen, dust, smoke and other pollutants that would otherwise enter the vehicle and possibly irritate the nose and lungs of the driver and passengers.
Most of these filters are highly efficient and have electrostatically charged fibers that do an excellent job of trapping even the smallest particles (down to 0.3 microns!). A human hair, by comparison, is about 40 to 70 microns across. Most cabin air filters will stop 100 percent of all particles that are 3 microns or larger in size and 95 to 99 percent of particles in the 1 to 3 micron size range.
Some cabin air filters also trap odors and are called “combination” filters. These type of filters have an extra layer of activated carbon that reacts with odors and other airborne pollutants to neutralize them before they become objectionable. The filters can even reduce the levels of carbon monoxide and oxides of nitrogen from the exhaust of other vehicles. The levels of these pollutants can be quite high in heavy stop-and-go traffic, and it’s not unusual for the concentration of these pollutants to be several times higher inside a vehicle than outside. Studies have shown that driver reaction times are slower when the driver is being affected by poor air quality.
Cabin air filters also prevent leaves, dirt, bugs and other debris from entering the HVAC (Heat Ventilation and Air Conditioning) system. This prevents the fan and control doors from becoming jammed with debris that could cause fan noise or affect the operation of the heater, air conditioner and defroster. Keeping the HVAC system clean also helps reduce the growth of odor-causing mold and other microbes on the A/C evaporator.
WHEN TO REPLACE
The recommended replacement interval for a cabin air filter depends on the type of filter (pleated paper or a combination filter with activated carbon) and the filter’s exposure to environmental pollutants.
As a general rule, most cabin air filters should be changed every 20,000 to 30,000 miles or more often depending on the size and capacity of the filter. Some vehicle manufacturers recommend replacing an odor-absorbing cabin air filter every 12,000 to 15,000 miles or once a year to keep the filter working at peak efficiency. Refer to the vehicle owner’s manual for specific service interval recommendations.
If a cabin air filter is neglected and is not changed for a long period of time, it can become clogged with dirt and debris. This will create an air restriction that can reduce airflow and the output of the heater, defroster and/or air conditioner. A complaint of poor heating or cooling, therefore, may be the result of a clogged cabin air filter that is long overdue for replacement.
Most cabin air filters are flat panel filters, but some have unusual shapes so they will fit the HVAC inlet duct. The filter is usually located behind the glove box or at the base of the windshield in the cowl area over the HVAC inlet duct. The exact location can be found in the vehicle owner’s manual or a filter reference guide. On some applications, the filter may be in two sections to make installation easier.
Replacing a cabin air filter is fairly easy on most vehicles once its location has been determined, but on some, the glovebox or console must first be removed.
A related item your customer might want to buy would be an air freshener or some scented aerosol spray to mask smoke, animal odors or other smells. A cabin air filter can remove odors from incoming air but it won’t do anything for odors that may already be inside the vehicle. So if someone has been hauling around a wet dog or delivering pizza, it will take more than a cabin air filter change to get rid of the aromas.
3. CERAMIC AND NAO BRAKE PADS
Friction materials are made from a variety of ingredients. These include various types of fibers for reinforcement and heat management, fillers for friction control and wear resistance, other ingredients to suppress noise and resin to bind all of the other ingredients together. Up to 20 different ingredients may be used to achieve the optimum balance between the material’s friction coefficients, stopping power, pedal feel, wear resistance and noise characteristics. As a result, many brake pads and shoes are marketed according to the ingredients they contain. These include nonasbestos organic (NAO), ceramic, low-metallic and semi-metallic.
When the use of asbestos was discontinued in the U.S. because of concerns over possible health risks of asbestos dust, NAO friction materials were developed to replace asbestos. NAO materials contain kevlar and other kinds of fibers and generally provide good braking performance and quiet operation (no brake squeal). NAO is typically used for both “standard” and “economy” grade replacement linings and for rear linings on most drum brakes, as well as the pads on front disc brakes in many cars and trucks.
NAO linings are often dark gray or black. The “softer” nature of NAO linings helps dampen vibrations that can cause noise. But a softer lining usually lacks the wear resistance of harder materials. Because of this, NAO linings tend to wear faster, especially at high brake temperatures. They also give off black brake dust as they wear. The dust can stick to alloy wheels, giving them a dirty appearance. NAO friction materials work well at ordinary brake temperatures, but are more likely to suffer heat fade when the brakes get really hot. Consequently, NAO pads that are fine for everyday driving are not the best choice for performance cars, heavier vehicles (large SUVs and pickup trucks) or “severe use” applications such as police, taxi and emergency vehicles.
Friction materials that contain ceramic (silica-based) fibers or particles are usually referred to as “ceramic” linings. Ceramic brake pads were first used as original equipment on a few import cars back in 1980s. Today, nearly 75 percent of all new vehicles come factory equipped with some type of ceramic linings. This has created a growing demand for ceramic replacement linings in the aftermarket, which brake suppliers have responded to by introducing their own ceramic product lines.
Ceramic fibers are a good choice for brake linings because they have stable and predictable friction characteristics. The coefficient of friction doesn’t drop off as quickly as semi-metallics, nor does it fade as quickly as NAO as the brakes heat up. This is called “Mu Variability.” The more stable the friction characteristics are, the more consistent the brake pedal feels whether the brakes are hot or cold.
There is no standard industry definition for what constitutes a ceramic friction material, so the actual ceramic content can vary a great deal from one brand of ceramic friction linings to another. The ceramic content may vary from double-digit percentages to less than a few percent. The size of the fibers or particles may also range from 0.4 to as much as 80 microns in diameter (smaller is better say some suppliers, but others disagree).
Like any friction product, the real-world performance will vary according to the brand, formulation and application. As a rule, ceramic linings are marketed as premium grade linings that provide better braking performance, longer life and quiet operation. The lighter color of the ceramic friction material also produces less visible brake dust, so alloy wheels stay cleaner longer.
Most brake experts recommend replacing linings with same linings as before (or better, in the case of NAO). On vehicles that are originally equipped with ceramic linings, ceramic replacement linings should be installed. On vehicles that were originally equipped with NAO linings, ceramic linings can be used as an upgrade. But ceramic linings are usually not recommended as a replacement for semi-metallic brake pads in larger, heavier vehicles.
The type of brake pads that are installed on a vehicle also affect how long the rotors last. Rotors often have to be resurfaced or replaced because of excessive grooving, heat cracking, uneven wear, runout and warpage. Resurfacing can clean up minor surface imperfections, but every cut that’s taken reduces the thickness of the rotor and brings it closer to discard thickness. But if the rotors are badly worn, replacement is the only option.
Ceramic brake pads are marketed as being “rotor friendly” because they reduce rotor wear. Consequently, rotors last longer and may not have to be resurfaced or replaced when the pads are changed that can add up to significant savings over the life of a vehicle.
Many ceramic pads also have other special features that help reduce vibrations and noise. These include chamfers, slots and insulator shims.
Chamfers are angled or beveled edges on the leading and trailing ends of the pad that reduce “tip-in” noise when the brakes are first applied. Chamfers also reduce the surface area of the brakes slightly, which increases the clamping force applied by the pads against the rotors. This further helps to dampen sound-producing vibrations.
Slots are grooves cut vertically, diagonally or horizontally in the pads to reduce noise by changing the frequency of vibration from an audible level to a higher, inaudible frequency beyond the range of the human ear. Slots also help reduce brake fade by providing a path for water, dust and/or gas to escape.
Insulator shims provide a dampening layer to absorb and dissipate vibrations before they can cause noise. Some shims are installed on the backs of the pads, while others are molded into the pads themselves, or laminated onto the backs of the pads.
Other products a customer may need when replacing brake linings include brake grease for the backs of the pads, caliper mounts and shoe pads, new brake hardware for drum brakes and brake fluid.
4. FUEL PUMP
The fuel pump is the heart of the fuel system. On most late-model vehicles, an electric pump is mounted inside the fuel tank to supply fuel to the fuel injectors. The pump runs continuously after the key is turned on and the engine starts unless something goes wrong with the pump and it quits. A fuel pump failure causes the engine to stall and will prevent it from restarting.
Back in the days when engines had carburetors, replacing a fuel pump was not a big deal nor a major expense. The pump was mounted on the side of the engine and usually sold for $20 or less. Diagnosis was relatively simple, too. If it leaked or failed to pump fuel to the carburetor, it was bad.
With electric fuel pumps, it’s a different story. The pumps typically cost $150 to $300. The in-tank location also makes them difficult and expensive to replace. Labor alone can add a couple hundred dollars to the repair bill. Diagnosis can also be a challenge, even for experienced technicians.
For a fuel-injected engine to run properly, the fuel pump must be capable of generating pressure that meets the system’s operating requirements. Close enough is not good enough. The pressure delivered by the pump must meet specifications because that’s the way the engine is calibrated to run. If fuel pressure is even a couple pounds less than the specifications, it can cause problems. A weak pump that isn’t delivering adequate pressure can cause an engine to run lean, misfire and hesitate when accelerating.
The volume of fuel is just as important as pressure. A good fuel pump is usually capable of pumping at least 750 ml (3/4 quart) of fuel in 30 seconds. If it can’t, there’s a problem. The pump might be getting wear, a clogged fuel filter might be restricting fuel flow to the engine, or the pump might not be getting enough volts through its power circuit to run at normal speed. Loose or corroded wiring connections in the pump circuit, a bad relay or low system voltage can all affect the operation of the fuel pump.
Low fuel pressure can be caused by any of these factors, as well as a bad fuel pressure regulator. The regulator is a small valve with a spring-loaded diaphragm inside. The regulator’s job is to control fuel pressure to the injectors.
On most applications, the regulator is mounted on the engine’s fuel injector supply rail. But on engines with “returnless” fuel injection systems, the regulator is located in or on the fuel tank near the fuel pump. On the engine-mounted applications, the regulator has a vacuum line connection to the intake manifold. At idle, high vacuum in the intake manifold causes the regulator to bleed off fuel pressure and route the excess fuel back to the tank through a return line. As engine load increases and vacuum drops, the regulator bleed off less pressure to maintain the same relative pressure differential between the injectors and intake manifold.
If the regulator leaks internally, it may bleed off too much pressure, causing symptoms that mimic a bad fuel pump. Consequently, if the operation of the regulator isn’t checked, someone may replace the fuel pump unnecessarily. The regulator can be checked by pinching off or disconnecting the vacuum hose. This should cause an increase in fuel pressure. If fuel pressure is low, and pinching off the return line causes it to rise to normal levels, the regulator is leaking and should be replaced.
All too often, these “other” causes are overlooked and the fuel pump is replaced unnecessarily. When the new pump fails to perform any better than the old one, your customer may want to exchange the “defective” pump he just bought for another pump, or he may want to return it for a refund. Either way, it creates extra work for you, extra work (and cost) for your pump supplier (who has to warranty the returned pump) and extra work for the installer who has to change the pump a second or third time.
Misdiagnosis is a major issue with electric fuel pumps and costs everybody time and money. Unfortunately, to date there has been no easy way to bench test an electric fuel pump. Pump pressure can be tested on a vehicle by connecting a fuel pressure gauge to the fuel rail service connection or the fuel rail supply line. Fuel volume can be measured by disconnecting the supply line to see how much fuel the pump can delivery in 30 seconds, or by measuring fuel flow with a special flow meter.
Bench testing a fuel pump is a great way to verify its condition and can eliminate comebacks and unnecessary warranty returns. But until recently, there has been no way to safely bench test an electric fuel pump in a store. At least one aftermarket tool supplier is currently developing a fuel pump bench tester that should be available this fall. Several fuel pump manufacturers have also developed bench testing equipment that may be made available to jobber stores soon. When this equipment becomes available, it should be used to test every old pump, and to verify the operation of every new pump before it goes out the door.
WHY GOOD PUMPS GO BAD
A fuel pump is engineered to last the life of a vehicle, but it often fails to go the distance because of other factors. Dirt or rust inside a fuel tank can ruin a pump very quickly (which is why the fuel tank should always be inspected and cleaned or replaced if any contaminants are found inside when replacing a fuel pump).
Many motorists also have a bad habit of driving around with a low fuel level in their tank (under 1/4 tank). This can shorten the life of the pump and cause it to fail prematurely because the pump relies on the fuel for cooling and lubrication. Fuel tanks have internal baffles that are supposed to minimize fuel sloshing. Even so, whipping around a sharp corner, or braking or accelerating hard can sometimes starve the pump for fuel. And when the pump sucks air, it suffers the consequences.
As a fuel pump ages and its brushes wear, the pump may pull more amps than normal thorough its power supply circuit. This may cause the pump wires to run hot and melt or short out! If the damaged wiring harness is not replaced when the pump is changed, the replacement pump may not work at all or may not spin fast enough to generate normal pressure.
The fuel pump is part of the fuel tank sending unit assembly. The pump can be replaced separately (which costs less but requires more work and increases the risk of misassembly), or it can be replaced as a complete assembly (much easier but costs more).
Note: Some replacement pumps may not look exactly the same as the original. The reason for this is that some aftermarket pump suppliers have replaced “old technology” pumps with newer “turbine” style pumps that are more efficient and reliable.
The fuel strainer sock on the fuel pump inlet inside the tank should always be replaced with a new one when changing a pump. Also, if the old fuel tank is rusty, it should be replaced to prevent a repeat pump failure. The fuel filter should also be replaced.
5. HEAVY DUTY BATTERIES
Batteries store electric power for starting the engine, operating the truck’s lights and electrical accessories and for keeping the memories alive in the truck’s on-board control modules when the engine is not running.
All automotive and truck batteries (except the auxiliary batteries in hybrid vehicles) are lead-acid batteries that generate 12 volts D.C. (direct current). Most cars have only a single battery, but many diesel-powered light trucks have two, and big heavy-duty commercial trucks may have three or four. Truck batteries are built to more rugged standards than car batteries. This reduces the risk of vibration damage that could cause premature battery failure in over-the-road trucks that travel hundreds of thousands of miles a year.
Batteries have two posts: one for negative and one for positive. All trucks today have a negative ground electrical system with the negative battery post connected to the truck frame. Care must be used when connecting, charging or jump starting a battery because reversing the post connections can damage the battery and electrical system.
To function normally, a 12 volt lead-acid battery must be kept at or near full charge. The alternator maintains battery charge when the engine is running and also provides additional current to meet the truck’s other electrical needs. When the engine is not running, any lights or other electrical accessories in the cab or sleeper that are on will pull power directly from the batteries, causing them to slowly discharge and run down. If the batteries are low, they may not have enough reserve power to crank the engine fast enough for reliable starting, especially during cold weather. Batteries that are dead won’t crank the engine at all.
Batteries have a limited service life that depends on usage, temperature and operating conditions. With over-the-road trucks, battery life is typically three to four years. But in hot climates, battery life may be as short as two to three years. High temperatures increases evaporation of the water-acid solution (called the “electrolyte”) inside the battery.
Since water lost through evaporation in batteries with sealed tops cannot be replaced, the water level inside eventually drops below the tops of the cell plates, causing them to dry out. When this happens, the plates lose their ability to hold a charge and the battery’s storage capacity is reduced. Over-charging the battery can also cause increase water loss and damage the battery. Vibration and shock damage can also damage the cells and connections inside a battery, causing it to fail suddenly.
The batteries and charging system in a truck should always be tested if any of the batteries are low or weak. Testing will reveal battery condition as well as any problems with the charging system. As a rule, a good charging system should produce a charging voltage about 1.5 to 2.0 volts higher than battery voltage (about 13.5 to 14.2 volts on most trucks with the engine idling). This will vary by temperature and charge.
Cold Cranking Amps (CCA) - The number of amps the battery can deliver for 30 seconds at 0 degrees F while maintaining post voltage of 7.2 volts. For reliable cold weather starting, most trucks require 700 to 750 cold cranking amps. Larger displacement engines may require more cold cranking amps.
Cranking Amps (CA) - Same as CCA except it is measured at 32 degrees F.
Reserve Capacity (RC) - The battery’s staying power, as measured by how many minutes the battery will deliver 25 amps and still maintain a post voltage of 10.5 volts. The recommended RC for most truck batteries is 180 to 190 amps.
Amp Hour Rating (A/H) - This measures low current draw for 20 hours while maintaining a minimum post voltage of 10.5 volts at 70 degrees F.
Disconnecting the batteries will cause the radio, engine computer and other modules to forget certain settings. If a battery charger or auxiliary power source (such as a 9-volt “memory saver”) is not connected to the electrical system before the batteries are disconnected, a scan tool or other special procedure may be required to reset the affected module(s).
Replacement batteries must be a compatible “group size” so it will fit the battery tray and holddowns. Group 31 fits most Kenworth, Mack, Peterbilt and Western Star trucks. Also, the batteries must have the same or better CCA capacity as the original.
Most batteries are “dry charged” (pre-charged) at the factory for maximum shelf life. Even so, all batteries should be put a charger to bring them up to full charge before the are installed in the vehicle. This will reduce the risk of overworking the alternator should one or more batteries below.
Finally, batteries contain lead, which is a hazardous metal. Old batteries should be recycled to keep lead out of the environment.
Nothing lasts forever and headlights and other bulbs are no exception. After 1,000 or more hours of operation, the light-emitting tungsten filament eventually burns out, causing the lamp to fail. Vibration is another factor that can shorten the life of any bulb and headlights are always vulnerable to stones and debris kicked up by other vehicles, not to mention collision damage.
The loss of a headlight makes nighttime driving hazardous and may even attract the unwanted attention of the local police. A burned-out taillight, stoplight or turn indicator lamp creates a hazard for other motorists because these lamps signal a vehicle’s directional intentions to other drivers. Bulbs that provide illumination for instrumentation are also important because they allow the driver to monitor the speedometer and other gauges. Even something as simple as a failed trunk light or dome light can create an inconvenience when operating a vehicle after dark. So your job is to help customers see the light when they need a replacement lamp or bulb.
Years ago, all headlights were sealed beams. So if a customer needs a replacement headlight for a 1980s vintage or older vehicle, there are only a few basic sizes of round and rectangular beams: Those for two headlight applications (6014 round hi/low sealed beam and 6052 rectangular hi/low beam) and those for four headlight systems (4000 round low beam, 4001 round hi beam, 4652 rectangular low beam and 4651 rectangular high beam).
Most of these older style sealed beams were originally standard incandescent lamps. In 1978, the federal government revised its headlight regulations to allow the use of “halogen” sealed beams. Halogen lamps are brighter and last longer than regular lamps because the bulbs contain a small amount of bromine gas (one of five elements in the halogen chemical family). The bromine gas allows the use of a smaller, hotter tungsten filament because bromine redeposits the microscopic particles of tungsten that boil off the filament back onto the wire. This extends the life of the bulb and prevents the glass from darkening as the bulb ages.
Halogen lamps are a good upgrade for these older sealed beam applications because halogen lamps produce more light with the same or less current. Halogen sealed beams have an “H” prefix on their part numbers and are available in various sizes for round, rectangular and low-profile rectangular headlights.
How much brighter are they? A conventional incandescent bulb generates 16 to 18 lumens of light per watt, compared to 20 to 22 or more lumens per watt for a standard halogen bulb (some high output halogen bulbs produce as much as 28 to 33 lumens per watt!). The higher output of a halogen headlight throws more light on the road to improve nighttime visibility and extend the driver’s visual range. The light is also whiter than a regular incandescent bulb, which improves visibility too.
In 1983, the feds approved the use of “composite” headlight assemblies with plastic covers and replaceable bulbs. This gave the vehicle manufacturers more design freedom, reduced the lighting system’s vulnerability to stone damage and made it easier in many instances to replace a headlight. But it also spawned the introduction of a growing number of new halogen bulb configurations.
Some of the more popular replacement halogen bulbs include 9004, 9007, 9008 and H4 for two headlight systems, 9006, H1, H7 and H11 for low beam quad headlight applications, and 9005 and H9 for the high beam on quad lamp systems. For fog and auxiliary lamps, other popular halogen replacement lamp sizes include 9040, 9045, 9055, 9140, 9145, 9155, H3 and H8.
XENON: A STEP UP
In the late 1990s, two new types of “xenon” headlights were introduced. One type is the “High Intensity Discharge” or HID lighting system that uses a special high voltage bulb that contains no filament. Inside the HID bulb are two electrodes separated by a gap and a mixture of xenon gas, mercury and halide salts. A ballast unit steps up the base voltage supplied to the HID lamp to create an electrical arc between the electrodes. This produces a “plasma discharge” inside the bulb that gives off a very bright, bluish-colored light for better night vision and range.
HID lighting systems are much more efficient than standard halogen headlights, producing about 75 lumens per watt. And because an HID bulb has no filament to burn out, they last three to five times longer than a standard halogen bulb. But the required ballast electronics also makes HID lighting systems very expensive so they are used primarily on high end luxury cars and SUVs. HID replacement bulbs include D1S, D1R, D2s and D2R. Aftermarket HID lighting kits are also available to upgrade a vehicle’s lighting system.
A more affordable upgrade alternative are blue xenon headlights that can replace standard halogen bulbs. The blue bulbs have a tungsten filament like a standard halogen bulb, but also contain xenon gas that allows the bulb to burn hotter and brighter (up to 30 percent more light depending on the application). The special coating also gives the light a bluish cast that appears similar to that of a real HID lighting system.
FINDING THE RIGHT ONE
With all types of lighting applications, finding the right replacement bulb is essential. Small bulbs, in particular, can be difficult to match. Always refer to a lighting catalog or database for the vehicle application. Comparing bulbs and referring to the number on the old bulb is also a good idea, but keep in mind that the old bulb may not be the correct one for the application if it has been replaced before (maybe that’s why it burned out!). Two bulbs that appear to be the same may have different wattage and resistance ratings. Using the wrong bulb may cause premature bulb failure, circuit overloads or other problems.
On some newer vehicles, “light out” modules are used to sense failed bulbs and alert the driver when a lamp fails. If a replacement bulb does not have the same resistance and wattage rating as the original, it can sometimes cause the module to illuminate the “light out” warning lamp even though the bulb is working.
With halogen and xenon headlights, the lamp receptacle in the headlight housing and wiring connectors are configured differently to eliminate the risk of installing the wrong replacement bulb. Customers should be warned, though, not to touch the bulb itself because fingerprints can cause a high-temperature bulb to fail prematurely.
7. MOTOR OIL
Most people think motor oil is only a lubricant that reduces friction and wear inside an engine. But it also helps cool bearings, pistons and other parts, and helps prevent rust and corrosion. It also contains detergents that help keep the engine clean.
Motor oil is made up of various hydrocarbons refined from petroleum. The hydrocarbons are blended with other ingredients to create motor oils with unique properties for specific engine applications. Additives improve the lubricating qualities of the oil, reduce friction and extend the life of the oil and the engine.
Motor oils must meet certain requirements set forth by the vehicle manufacturers and the American Petroleum Institute (API). The API “service rating” of an oil certifies that it meets specific OEM quality and performance standards. The service rating is shown in the API “Service Symbol Donut”on the product label. There may also be an “API Certified for Gasoline Engines” seal on the label.
The current service category rating for gasoline engines is “SM,” introduced in November 2004 for 2005 and newer engines. SM-rated oils along with the previous “SL” (2001) and “SJ” (1997) ratings, are backwards compatible and can be safely used in older engines.
For diesel engines, API has a separate rating system. The current category is “CI-4” (introduced in 2002 for newer diesels that have exhaust gas recirculation). The previous CH-4 (1998), CG-4 (1995) and CF-4 (1990), can all be used in older four-stroke diesel engines. CF-2 (1994) is the API classification for two-stroke diesels. API also gives oils an “Energy Conserving” rating if the oil meets certain criteria for reducing friction and oil consumption and for improving fuel economy.
Motor oils that meet the current API SM rating may also meet the International Lubricant Standardization and Approval Committee (ILSAC) “GF-4” specifications for North American and Asian vehicles. Meeting this specification is indicated on the label by the API Certification Mark, commonly referred to as the Starburst Symbol.
Motor oils are also graded according to their “viscosity” (thickness). Viscosity refers to how easily oil pours at a specified temperature. Thinner oils have a water-like consistency and pour more easily at low temperatures and thicker oils have a more honey-like consistency. Thin is good for easier cold weather starting, reducing friction and improving fuel economy, while thick is better for maintaining film strength and oil pressure at high temperatures and loads.
The viscosity rating of a motor oil is determined in a laboratory using various test procedures. The viscosity of the oil is measured and given a number, which refers to the thickness of the oil (which some people call the “weight” of the oil, but has nothing to do with the oil’s actual weight in kilograms or ounces). The lower the viscosity rating, the thinner the oil and the higher the viscosity rating, the thicker the oil.
Viscosity ratings for commonly used motor oils typically range from zerp up to 50. A “W” after the number stands for “Winter” grade oil, and represents the oil's viscosity at zero degrees Fahrenheit. Low viscosity motor oils that pour easily at low temperatures typically have a “5W” or “10W” rating. There are also 15W and 20W grade motor oils.
Higher viscosity motor oils that are thicker and better suited for high temperature operation typically have an SAE 30, 40 or even 50 grade rating.
These numbers, by the way, are for “single” or “straight” weight oils. Such oils are no longer used in late model automotive engines but may be required for use in some vintage and antique engines. Straight SAE 30 oil is often specified for small air-cooled engines in lawnmowers, garden tractors, portable generators and gas-powered chain saws.
Most modern motor oils are formulated from various base stock oils, which include both conventional and synthetic (polyalphaolefin) oils. Many 5W-30 conventional motor oils, for example, actually contain some synthetic base oil even though the product may not marketed as a synthetic blend.
Blending various base stocks and grades of oil creates a “multi-viscosity” oil that has good cold-flow characteristics and good high temperature film strength. Then the various additives are blended in to complete the formulation. Up to 25 percent of the contents in a quart of conventional oil is additive. In synthetic oil, less additives are needed (maybe only 12 to 15 percent). The additives include detergents, viscosity modifiers, friction modifiers, seal additives, anti-oxidants, anti-wear agents, corrosion inhibitors and pour depressants. Some racing oils typically have a higher dose of zinc to provide extra protection in high-revving, high-load applications.
Most vehicle manufacturers today specify 5W-30 or 10W-30 motor oil for year-round driving. Some also specify 5W-20. Many overhead cam engines require 5W-30 to speed lubrication to the camshaft and valvetrain components after a cold start. Refer to the vehicle manual for specific oil viscosity recommendations, or the markings on the oil filler cap or dipstick.
As mileage adds up and internal engine wear increases bearing clearances, switching to a slightly higher viscosity oil can prolong engine life, reduce noise and oil consumption (switching from say a 5W-30 to a 10W-30).
Oil life depends on many factors including driving conditions (speed,load, idle time, etc.), environmental factors (temperature, humidity, airborne dirt) and engine wear. As the miles add up, motor oil loses its ability to perform and gets dirty. The additives wear out and the oil is no longer able to lubricate and protect like it did when it was new. Short trips and stop-and-go driving (especially during cold weather or extremely hot weather) make the oil wear out more quickly. Many motorists think this kind of driving is “normal.” But it is actually “severe service,” so drivers should follow a severe service schedule. Severe service includes frequent trips under four miles, prolonged high speed driving during hot weather, towing a trailer and driving on dusty roads (gravel roads).
Changing the oil and filter every 3,000 miles or six months, which ever comes first, provides the best all-round protection for the average driver. Some vehicle manufacturers recommend extended oil change intervals of up to 7,500 miles or more. But some have experienced oil sludging and expensive engine damage as a result of pushing the interval too far. Older high-mileage engines (over 75,000 miles) with worn rings and cylinders should have the oil changed at 3,000 miles. Special “high mileage” motor oils with extra wear additives and seal conditioners are a good choice for these applications. Engines that are turbocharged or supercharged, as well as diesels, are also hard on the oil, so 3,000 miles oil changes are usually recommended for these applications, too.
Some late-model vehicles have no specific mileage recommendation for oil changes, but use an “oil reminder light” (not to be confused with the oil pressure warning light) to indicate when the oil should be changed. Be aware that these systems generally do not monitor oil condition or the oil level, but only estimate oil life based on hours of engine operation, temperature and miles driven.
8. RIDE CONTROL
Shock absorbers and struts dampen the motions of the suspension to provide a smooth, comfortable and safe ride. Some OEM shocks have electronic valving that allows the driver or a body control module to adjust the dampening characteristics of the shocks or struts to changing driving conditions. Electronic dampers may use a solenoid or an electric stepper motor for this purpose. The latest technology is to use a special “rheological” magnetic fluid that changes its viscosity when a current is passed through it.
Most shocks and struts today are “gas-pressurized” with nitrogen to minimize fluid foaming when the piston is pumping back and forth. Foaming creates bubbles in the fluid, which offer less resistance to the piston. The result is “shock fade” as the damper loses its ability to provide adequate ride control.
Gas shocks and struts come in one of two basic varieties: monotube and twin tube. Monotube dampers have all the major components contained within a single large tube and typically use a very high-pressure charge. The gas charge is separated from the hydraulic fluid by means of a floating piston in the top or bottom of the tube. Monotube shocks are used primarily on performance vehicles with stiffer handling suspension.
Twin tube shocks and struts are the more common design. The gas charge is contained in the outer chamber (fluid reserve tube) and is typically lower than that of a monotube.
Because the damping characteristics of shocks deteriorate gradually over time, the decline in ride control often passes unnoticed. Consequently, many motorists are unaware how weak their original shocks and struts have become. They get used to the way their vehicles ride and handle, and may not realize they need new shocks or struts.
Although you won’t find a recommended replacement interval for shocks or struts in a vehicle owner’s manual, one leading aftermarket shock supplier says shocks and struts should be replaced every 50,000 miles and has solid research to back up the recommendation.
ASK FOR THE SALE
Asking your customer how his vehicle has been riding lately may get him to thinking and may reveal a need for replacement or upgrading. Ask him how his vehicle handles when cornering, stopping, accelerating or driving in a cross wind. Excessive body sway or rocking is a sure sign of inadequate ride control. How does the vehicle ride over tar strips or on rough roads? A rough or bouncy ride could be improved with new shocks or struts. Does the suspension bottom out when the vehicle is heavily loaded, or does the steering wheel shudder at every railroad crossing?
A “bounce test” is still a valid means of checking the dampening ability of shocks and struts. If the suspension continues to bounce more than once after bouncing and releasing the bumper or body, it indicates weak shocks and/or struts that should be replaced.
If the original dampers are worn out or not up to the task, recommend a new set of shocks and/or struts as a way to rejuvenate or upgrade ride control performance. Replacement would certainly be necessary if a vehicle has a bent or damaged shock or strut piston rod, broken mounting hardware, or fluid leaking from a damper. Struts should be replaced if severely corroded.
Shocks and struts are generally replaced in pairs though this isn’t always necessary if a damaged low-mileage part is being replaced. It is necessary when upgrading a suspension because of differences in valving characteristics. The dampers on both sides of an axle should always offer the same resistance.
Upper strut bearing assemblies on front struts are often overlooked, but may also need replacing. The bearings are sealed assemblies and cannot be lubricated. If rusted, loose, worn, noisy, binding or damaged, they must be replaced. Symptoms include:
Steering noise such as snapping, popping, creaking or groaning sounds when turning.
Suspension noise such as clunking, rattling or popping on rough roads.
Increased steering effort brought on by binding in the bearing plate.
Steering snap back after turning caused by a frozen bearing assembly and spring wind up
“Memory steer” in which the car doesn’t want to go straight after turning due to binding in the upper mount.
If a DIY customer is replacing a strut that has a coil spring around it, he will need an appropriate spring compressor to disassemble the strut or you can sell him a preassembled strut assembly that makes installation much easier (and safer!).
Replacing struts changes the alignment of the front wheels, so a wheel alignment is usually necessary after new front struts have been installed. Also, if brake lines have to be opened to replace a strut, the brakes must be bled after the job is finished to remove trapped air.
Additional chassis parts that may have to be replaced include springs, tie rod ends, lower ball joints, lower control arm bushings, steering rack mounts and wheel bearings.
9. SEMI-METALLIC BRAKE PADS
Semi-metallic disc friction materials are typically designed for hard-working, high-temperature brake applications. They are used for the front disc brakes on many larger SUVs and pickup trucks, as well as the front brakes on larger, heavier cars, performance cars and “severe-use” applications such as police cars, taxis and emergency vehicles.
One way to identify semi-metallic pads is by their appearance. They are usually silver with the chopped steel fibers clearly visible. They are also magnetic. Some semi-met pads also have an outer coating of titanium or some other “transfer” material that aids break-in and helps suppress noise.
Semi-metallic pads are generally considered to be a “premium” grade product with features such as chamfers, slots and insulator shims to reduce vibrations and noise.
The chopped steel and other metal fibers in the pads allow semi-metallic brake linings to handle higher braking temperatures better that most other kinds of pads. Steel is a good conductor of heat and helps pull heat away from the rotors. This allows the pads to handle high brake temperatures with less fade. Nonasbestos organic (NAO) and ceramic friction materials, by comparison, do not conduct heat as well as semi-metallic materials and cannot withstand the kind of heat that semi-metallic pads can.
Above 500 to 600 degrees Fahrenheit, the hot friction coefficient of most NAO and ceramic friction materials drops dramatically. At the same time, pad wear shoots up. Most semi-metallics, by comparison, remain relatively stable at brake temperatures above 500 degrees and do not exhibit the same rate of wear as NAO or ceramic pads. That’s why semi-metallic pads are usually the best choice for hard working, high temperature applications where heat resistance is so important.
The amount of steel used in a “semi-met” formula may range from 20 percent to as much as 60 percent or more. The amount varies depending on the friction formula and application. By comparison, the steel content in “low-met” pads is usually 20 percent or less.
The total metallic content in the material, however, is not as important as how the steel fibers are combined with all of the other ingredients. The total package is what counts because it determines the hot and cold friction characteristics, stopping power, fade resistance, noise and wear attributes of the final product.
Generally speaking, semi-metallic pads with high steel content are fairly hard so they may be more prone to vibrate and squeal when braking than NAO pads or ceramic pads. A rough rotor surface, worn calipers, or missing insulator shims or other hardware can make any type of brake pad noisy. But with semi-metallic pads, it is especially important to make sure the rotor finish:
Meets OEM specifications;
The pads are installed properly;
The calipers are not worn to minimize any noise issues.
Semi-metallic pads with high steel content have good wear characteristics and can last a long time, especially when brake temperatures are elevated. But the pads can also be rough on rotors. Rubbing steel pads against cast iron rotors will produce more rotor wear than rubbing softer friction materials against the rotor. Because of this, the rotors often need to be resurfaced or replaced by the time a set of semi-metallic pads are worn out.
Semi-metallic friction materials typically require a little more pedal effort when they are cold and work best when the brakes are warm or hot.
Vehicles that were originally equipped with semi-metallic pads should usually be relined with semi-metallic replacement pads. This is especially important on larger SUVs and pickup trucks where the brakes tend to run hotter. Substituting any other type of pad could increase pad wear and the risk of brake fade.
Semi-metallic pads can also be a good upgrade from ordinary NAO pads or ceramic pads for performance applications or vehicles that may be subjected to harder than normal driving (police cars, taxis, emergency vehicles, etc.). The best advice here is to always follow your brake supplier’s application recommendations and guidelines.
As with all types of friction materials, other products to recommend include brake grease for the backs of the pads, caliper mounts and shoe pads, brake hardware for and brake fluid.
Computerized engine control systems do an amazing job of keeping engines in good tune, minimizing emissions and maximizing performance and fuel economy. To keep everything humming at peak efficiency, the computer needs good inputs from all of its sensors. Key among these are the oxygen (O2) sensors.
The O2 sensors located in the exhaust manifolds, provide the essential feedback for the fuel control loop that regulates the air/fuel mixture. On V6, V8 and V10 engines, there is one O2 sensor in each exhaust manifold. On four and straight six engines, there is usually only one O2 sensor in the exhaust manifold.
Oxygen sensors read the amount of unburned oxygen in the exhaust. On most applications, the O2 sensor sends either a “lean”signal (too much air going into the engine and not enough fuel to burn it all completely) or a “rich”signal (too much fuel and not enough air) to the Powertrain Control Module (PCM). The computer then adds or subtracts fuel to rebalance the air/fuel mixture.
The feedback process begins shortly after the engine is started and the O2 sensors are hot enough to produce a signal. The O2 sensors have internal heater circuits that bring them up to operating temperature (about 650 degrees Fahrenheit) in a minute or less. The feedback process then continues as long as the engine is running. The constant changes in the air/fuel mixture cause the O2 sensor voltage signal to flip-flop back and forth between rich and lean.
On a growing number of late-model vehicles, a more sophisticated “wide radio air fuel”(WRAF) type of oxygen sensor is now used. Instead of producing a rich/lean voltage signal, this type of O2 sensor tells the computer the exact air/fuel ratio of the exhaust that is coming out of the engine. This improves fuel control and lowers emissions even more.
The signal from the oxygen sensors is very important because of its impact on emissions and fuel economy. If an O2 sensor is not working correctly, it typically causes the engine to run rich, pollute and waste fuel.
On 1996 and newer vehicles (as well as some 1994 and 1995 models), there is one or more additional O2 sensors located in the exhaust system (usually behind the catalytic converter). These are called “downstream” O2 sensors, and their purpose is to monitor the operating efficiency of the converter. The converter reburns pollutants in the exhaust, so if the converter is not working properly tailpipe emissions can rise sharply.
O2 SENSOR PROBLEMS
Oxygen sensors must react quickly for the computer to maintain the best performance, fuel economy and emissions. As the sensors age, they may become sluggish and respond more slowly to changes in the exhaust. This may cause emissions and fuel consumption to rise.
Contamination can also ruin an O2 sensor. Contaminants include silicone from internal engine coolant leaks (bad head gasket or cracked combustion chamber), and phosphorus if the engine burns oil (due to worn valve guides or piston rings).
Replacing a sensor that has died because of contamination may temporarily restore normal engine operation. But unless the underlying problem that caused the sensor to fail is diagnosed and repaired, the replacement sensor will suffer the same fate. Sooner or later the Check Engine light will be back on and the engine will need another O2 sensor.
The operation of the O2 sensors as well as most of the other sensors on a vehicle can be monitored with a scan tool. But the Onboard Diagnostic System II (OBD II) system does the same thing every time the engine is started and the vehicle is driven. As long as the Check Engine light remains out, the sensors should be functioning well enough to keep the vehicle’s emissions within acceptable limits.
Other important sensors include the coolant sensor (monitors engine temperature), throttle position (TPS) sensor (monitors throttle opening), manifold absolute pressure (MAP) sensor (monitors intake vacuum and engine load), mass airflow sensor (monitors air coming into the engine), knock sensor (detects detonation), and the vehicle speed sensor (VSS). Problems in any of these sensors can upset engine operation and cause various emissions and driveability issues.
When a sensor fault occurs that affects emissions, the Check Engine light will usually come on and the computer will set a Diagnostic Trouble Code (DTC) that corresponds to the fault. The code can be read by plugging a code reader or scan tool into the vehicle's diagnostic connector.
The self-checks run by the OBD II system are called “monitors,” and the “ready”status of these monitors can be determined with a code reader or a scan tool. If all the monitors have run and no faults have been detected, the vehicle is within emissions compliance. It should pass an OBD II “plug-in”emissions test, and should probably be running normally.
When a sensor fails, it must be replaced to restore normal engine operation. Diagnosis usually requires some additional testing once a fault code has been read. Accurate diagnosis is absolutely essential to prevent mistakes. Many sensors are replaced unnecessarily because they were misdiagnosed. For example, somebody read a code, assumed the sensor was bad and installed a new sensor. Sometimes it fixes the problem and sometimes it doesn’t. Sensors are expensive, so they should not be replaced unless all other possibilities have been ruled out.
Most sensors do not have a recommended service or replacement interval an most sensors are replaced only after they have failed. Even so, a leading supplier of O2 sensors says replacing high mileage O2 sensors before they fail may improve fuel economy, reduce emissions and avoid annoying driveability issues. They recommend replacing the O2 sensors in 1980s and older vehicles at 50,000 miles, and 1990s and newer vehicles at 100,000 miles.
Replacement O2 sensors must be the same basic type as the original (heated or unheated), have the same number of wires (one to four) and have the same performance characteristics and heater wattage requirements. Installing the wrong O2 sensor can upset engine performance and possibly damage the heater control circuit.
11. SPECIALTY CHEMICALS
It seems that chemical suppliers are trying to outdo each other by expanding lines with more and more new specialty products that are targeted at narrower and narrower potential buyers. It’s vertical marketing that’s squeezing horizontal shelf space to the max.
While this may be giving consumers a broader range of choices, in the real world it creates an overload of choices many consumers find confusing. That’s why you need to know the products on your store shelves, and know how the differ from one another.
Take motor oil, for example. Your store likely carries multiple brands of oil, and each brand not only offers a range of viscosities (5W-30, 10W-30, etc.), but also “specialty” products such as full synthetic oil and blended synthetic oil. Some offer oil specially formulated for SUVs and trucks. Others have special blends for high mileage engines. There are also special oils for easier winter starting (like 0W-30 synthetic or synthetic blend).
Choosing the “right” oil, therefore, means taking a number of things into consideration, such as how the vehicle is driven, the mileage on the engine, climate conditions, whether the customer is willing to spend more for a synthetic, and so on.
Choosing the right automatic transmission fluid (ATF) can also be confusing. Most late-model vehicles use a “friction modified” fluid designed to work with the electronic shift controls and torque converter clutch. But each vehicle manufacturer has its own specifications, and although GM and Ford are similar, Chrysler is different and so are many imports. If your customer chooses the wrong fluid, he may end up with transmission problems.
How about power steering fluid? Some vehicles use ATF in their power steering systems, others require a specially formulated fluid that contains additives that are compatible with the seals in the pump and steering rack. A universal power steering fluid may work in most applications, but there are exceptions.
Helping a customer choose the right product, therefore, means reading product labels and literature so you know how the different products compare and which might offer the best value, protection and/or life for your customer’s vehicle.
Many products that fit into the specialty chemical category are essentially “problem solvers” designed to satisfy one or more specific needs. Some products provide very targeted solutions to specific kinds or problems while others have a wider spectrum of potential applications.
There are specialty chemical products to:
Clean dirty fuel injectors;
Clean dirty throttle bodies;
Clean the entire fuel system;
Boost the octane rating of the fuel to stop engine knock;
Remove fuel varnish deposits from the intake
Remove carbon from the valves, pistons and combustion chambers;
Remove sludge and varnish from the crankcase;
Prevent gas line freeze during cold weather;
Condition diesel fuel so it won’t gel during cold weather;
Replace lead in older engines that required leaded gasoline;
Stop engine oil leaks;
Stop oil burning;
Stop engine noise;
Reduce friction for more horsepower and better fuel economy;
Restore lost pep and power;
Protect engine parts against premature wear;
Soften seals and stop transmission oil leaks;
Condition the transmission fluid for smoother shifts;
Stop power steering leaks;
Helps to find power steering leaks;
Stop coolant leaks;
Lubricate the water pump;
Clean the cooling system;
Improve the cooling performance of the cooling system;
Clean brake parts;
Degrease the engine or other parts;
Loosen rusty fasteners;
Condition belts to stop noise;
Lubricate almost anything;
Undercoat the chassis to deaden sound and prevent rust;
Neutralize rust and corrosion;
Remove and prevent rust and corrosion;
Inflate flat tires;
Clean dirty tires;
Enhance the appearance of the tires;
Remove dirt, spots and stains from carpets;
Clean, protect and preserve
Add shine to upholstery and other surfaces; and
Clean and protect exterior plastic surfaces.
Think of an automotive maintenance, performance or cleaning “need” and you can probably find a specialty chemical product that addresses it. Store shelves are full of such products, so it pays to keep yourself up-to-date with what’s available and what’s new.
Though most specialty chemical products are designed to sell themselves right off the shelf or end-cap display, many customers walk right down the chemical aisle without really taking the time to stop and shop all the possibilities. Customers often have tunnel vision. They are looking for a particular type of product, say a bottle of fuel injection cleaner or a product to stop a leak, but they don’t really look at much of anything else. They may be in a hurry or don’t feel like browsing.
One way to open their eyes to other possibilities is to ask your customer if he has tried a particular product when he makes his purchase. You might mention the product’s unique features or benefits (which you can probably get right off the label or packaging). The product doesn’t even have to be related to what he is buying. The idea is to get him to at least think of the product as something he might buy. Engaging the customer in this type of simple conversation can spark his interest and often results in additional sale especially if a product happens to be on sale.
You should also keep specialty chemical products in mind when selling maintenance and repair parts. If a customer is buying brake parts, he could probably use a can of aerosol brake cleaner. If a customer is buying spark plugs, filters or other maintenance parts, you might recommend a can of fuel system cleaner or engine top cleaner. A customer who is buying motor oil may need a crankcase additive that will slow oil burning and/or reduce oil leakage (so his engine will use less oil). You get the picture. Just think of a specialty chemical that is related to the part a customer is buying or a chemical that might be needed to replace a part (like penetrating oil), then bring it to their attention by mentioning its uses. They may appreciate your suggestion, ask you a question about why the product might be needed or ask how to use it. Many times, this kind of interaction can lead to an additional sale.
Of course, you can legally sell just about any specialty chemical in your store, with one exception: Freon.
Those who work in auto parts stores should know that it’s illegal to sell R-12 to noncertified do-it-yourselfers. Federal law restricts the sale of R-12 to anyone who has not passed an accredited EPA certification course for refrigerant recovery and recycling.
If you’re not asking for credentials, you should be. The EPA is cracking down on jobbers and individuals who sell R-12 to noncertified users. In Maryland, the EPA fined one man more than $15,000 for selling R-12 to an uncertified customer. That’s an expensive mistake to make.
For now, small cans of R-134a may still be sold to anyone who walks in the door, but that may change. The EPA would like to ban R-134a can sales to noncertified individuals in order to reduce the growing problem of refrigerant cross-contamination. Wisconsin has already banned the practice, but in most areas there are no restrictions on R-134a sales. The California Air Resources Board is currently proposing a ban on sales of R-134a to those who are not certified.
Up until 1995, R-12 was used in virtually all automotive A/C systems. The refrigerant was phased out of production in the U.S. and many other industrialized nations because it is a chlorofluorocarbon (CFC), a man-made chemical that contains chlorine. R-12 and other CFCs were banned under the revisions to the Clean Air Act because scientists discovered that the chlorine from CFCs was destroying the Earth’s ozone layer. This region of the upper atmosphere shields us against harmful ultraviolet radiation from the sun. R-12 was replaced with R-134a, a more ozone-friendly gas that does not contain chlorine.
Other gasses cannot be used as refrigerants in automotive applications because they are flammable. Gases such as propane, butane and other flammable hydrocarbons have the right physical characteristics and are used as refrigerants in some nonautomotive applications, but are too dangerous to use in vehicles because of the potential for explosion or fire.
Flammable refrigerants are illegal under federal law and have also been banned by many states and local regulations. Yet flammable “substitutes” for R-12 keep turning up in the aftermarket and are often responsible for contaminating the refrigerant in many older vehicles. Bottom line: don’t sell such products.
12. WATER PUMPS
Engines run hot! Almost a third of the heat energy produced by combustion is absorbed by the engine itself. That’s why engines need a cooling system. The cooling system absorbs the engine’s waste-heat and prevents the engine from overheating and self-destructing.
To get rid of the heat, the coolant inside the engine is pumped to the radiator by the water pump. The pump is usually located on the front of the engine and is driven by either the serpentine belt or the overhead cam timing belt. The pump itself is relatively simple, with a metal or plastic impeller mounted on a shaft. The shaft is supported in the water pump housing by a bearing and seal assembly.
On most engines, the water pump pulls coolant in through the lower radiator hose and routes it into the block and heads. The coolant then circulates back to the radiator through the thermostat housing and out the upper radiator hose. On some engines with “reverse flow” cooling systems, the pump routes the water into the cylinder heads first. Many water pumps also have additional inlet and outlet ports for heater hose and bypass connections.
Water pumps work hard. As the miles add up, so does the wear and tear on the pump shaft bearing, seal and impeller. Erosion inside the pump can wear away the vanes on the impeller, causing it to pump less efficiently as the impeller is eaten away. This may lead to engine overheating on hot days or when the engine is working hard. If the water pump seal becomes worn, coolant will leak past the pump shaft or out of the small vent hole on the housing. The loss of coolant will eventually cause the engine to overheat. If the pump shaft bearing fails or seizes, the shaft may break. Other symptoms of bearing wear may include pump noise (rumbling, chirping or growling) and fan or pulley wobble.
One way to identify a water pump with bad shaft bearings is to check pulley or fan play with the engine off. The pulley or fan should not move when wiggled sideways by hand. Pressure testing the cooling system can also reveal a leaky shaft seal inside the water pump.
Replacing a water pump that is leaking or failing is a repair that can’t be postponed for very long especially if the pump is leaking coolant. Cooling system sealers usually can’t stop a shaft seal leak. Unless the steady loss of coolant is stopped or constantly replenished by adding more coolant, the engine will overheat. This should be avoided because overheating can damage the head gasket and other engine parts that are expensive to replace. Better to replace a failing water pump as soon as possible than to risk major engine damage!
A new or remanufactured water pump may cost anywhere from $20 to $100 or more depending on the application. The supplier your company chooses should offer everthing you need to properly service your customers, and that includes accurate cataloging a dedicated sales force, help with inventory issues and high fill rates.
The labor required to change the pump will vary depending on the pump’s location. On some engines, the pump is relatively easy to change. On others (such as OHC engines where the pump is driven by the timing belt and the pump is located behind the timing belt), pump replacement requires a lot of disassembly. On some OHC applications, it’s probably a good ideal to go ahead and replace the timing belt if the pump has failed. If the belt has never been replaced or it has more than 60,000 miles on it, changing the timing belt and water pump at the same time saves the labor of having to do essentially the same job twice.
The condition of the cooling system should be carefully checked when replacing a water pump. Rust and sediment in the coolant can ruin a new pump, so the system should be flushed and refilled with fresh coolant if the old coolant is dirty or is more than a few years old.
Make sure your customer gets the correct replacement pump before he leaves your store this is where accurate cataloging is essential. If possible, compare the old and new pumps to make sure the pump housing, bolt configuration and fittings are the same. Also, compare the length of the pump shaft. Some engines use similar pumps that have different length shafts. This may cause interference or clearance problems if the wrong pump is installed.
Here’s something else to watch out for: On some engines with serpentine belts, the water pump turns in the opposite direction as the same pump does on an engine with conventional V-belts. The pumps may appear to be the same, but the impellers are backwards and are not interchangeable.
On rear-wheel drive vehicles that have a fan clutch, the lifespan of the clutch and water pump are about the same. Most experts recommend replacing both if either fails. Fan clutches lose their grip as they age and do not cool as efficiently as when they were new. This may lead to overheating on hot days or when pulling a heavier than normal load.
Other parts your customer may need include new hoses (upper and lower radiator loses, heater hoses and clamps), a new thermostat (recommended for high mileage engines or any engine that has overheated), possibly a new radiator cap (pressure test the old one to see if it holds the specified pressure), and fresh coolant.
When the water pump is installed, the pump mounting surface must be perfectly clean (no old gasket remnants) and dry to prevent leaks. The water pump gasket (if used) that fits between the pump housing and engine should be coated with sealer on both sides (sealer is not needed with rubber o-rings or molded rubber gaskets). If the pump mounts without a gasket, your customer will need the specified sealer: either an anaerobic sealer or RTV silicone. Water pump bolt threads that extend into the water jackets must be coated with sealer to prevent leaks. Bolts should be tightened to the recommended specs.