Monthly Archives: March 2017

Tips To Fix Common Brake Problems

Brake problems usually indicate the need for certain repairs or replacement parts, so here is a quick review of some common fixes:

LOW BRAKE FLUID This may be the result of worn disc brake pads, or it may indicate a leak in the brake system. If the BRAKE WARNING LIGHT is also on, most likely the problem is a leak (though the Brake Warning light may also come on if the master cylinder reservoir has a fluid level sensor). Leaks are dangerous because they can cause brake failure. The brake calipers, wheel cylinders, brake hoses and lines, and master cylinder all need to be inspected. If a leak is found, the defective component must be replaced. Your vehicle should NOT be driven until the leak can be repaired.

LOW BRAKE PEDAL The brake pedal may be low if the shoe adjusters on rear drum brakes are rusted or sticking and not compensating for normal lining wear. Adjusting the rear drum brakes may restore a full pedal. But unless the adjusters are cleaned or replaced the problem will return as the linings continue to wear. Other causes include worn brake linings or a fluid leak.

SPONGY OR SOFT BRAKE PEDAL This is usually caused by air in the brake system, either as a result of improper bleeding, fluid loss or a very low fluid level. The cure is to bleed all of the brake lines using the sequence recommended for your vehicle. Another possible cause is a rubber brake hose that is “ballooning” when the brakes are applied.

EXCESSIVE BRAKE PEDAL TRAVEL Possible causes include worn brake linings front or rear (or both), misadjusted drum brakes, or air in the brake lines. This can be dangerous because the brake pedal may run out of travel before the brakes are fully applied. Pumping the pedal when you apply the brakes usually helps, but you need to diagnose and fix the problem.

PEDAL SINKS TO FLOOR This may occur while holding your foot on the brake pedal at a stop light. If the pedal goes slowly down, it means the master cylinder is not holding pressure. This is also a potentially dangerous condition because a worn master cylinder or a leak in the hydraulic system may cause the brakes to fail.

BRAKE PEDAL PULSATION Indicates a warped brake rotor (one that is worn unevenly). The rotor needs to be resurfaced or replaced. The faces of a rotor must be parallel (within .0005 inch on most cars) and flat (no more than .003 inches of runout as a general rule on most cars and trucks, but some cars cannot tolerate any more than .0015 inches of runout). Excessive runout can be corrected by resurfacing the rotors in place with an on-car brake lathe, or by installed special tapered shims between the rotors and hub to correct the runout.

SCRAPING NOISE FROM BRAKES Usually indicates metal-to-metal contact due to worn out disc brake pads (or shoes on rear drum brakes). Your vehicle needs a brake job now! In fact, it is overdue for a brake job. Your vehicle is also dangerous to drive in this condition because it may take longer to stop. The rotors and/or drums will likely have to be resurface or replaced because you waited too long to replace the pads and shoes.

BRAKE SQUEAL Can be caused by vibrations between the disc brake pads and caliper, or the pads and rotor. Harder semi-metallic brake pads tend to be noisier than nonasbestos (NOA) or ceramic brake pads. The noise can usually be eliminated by replacing the old pads with new ones (ceramic pads are usually the quietest, but may not be available for some applications because the vehicle requires semi-metallic pads), and resurfacing or replacing the rotors. Installing noise dampening shims behind the pads, spraying the rotors with some type of aerosol brake noise control compound and/or applying a small amount of high temperature brake grease (never ordinary grease) to the backs of the pads can also help suppress noise. Also, if any pad mounting hardware such as shims or anti-rattle clips are missing, these should be replaced.

BRAKE CHATTER Can be caused by warped rotors or rotors that have been improperly finished.

GRABBY BRAKES Oil, grease or brake fluid on the brake pads will cause them to slip and grab. This may create a jerky sensation when braking. The cure is to inspect the pads for contamination, replace them if they have oil, grease or brake fluid on them, and eliminate the cause of the contamination (such as replacing a leaky brake caliper or curing a nearby oil/grease leak). Badly scored drums or rotors can also cause uneven or grabby braking. Resurfacing may be needed.

DRAGGING BRAKES This can cause a steering pull and/or increased fuel consumption. The constant drag will also accelerate brake wear and cause the brakes to run hot (which can increase pedal effort and the risk of brake fade if the brakes get too hot). Dragging brakes can be caused by weak or broken retracting springs on drum brakes, a jammed or corroded disc brake caliper piston, a floating caliper with badly corroded mounting pins or bushings (uneven pad wear between the inner and outer pads is a clue here), overextended drum brake self-adjusters or a sticky or frozen emergency brake cable.

BRAKES PULL TO ONE SIDE If your vehicle suddenly swerved to one side when you apply the brakes, there is uneven braking side-to-side. This usually means one front brake is not working properly. The pull will be toward the side with the good brake (because it is doing all the work). Brake pull can be caused by brake fluid, oil or grease on the brake pads, a stuck caliper, a blockage in the brake line to one of the front calipers, or sometimes loose wheel bearings. A brake pull can also be caused by different types/brands of brake pads side-to-side on the front brakes. Different friction materials have different friction characteristics, so the brakes will pull toward the side that generates the most friction.

HARD BRAKE PEDAL Lack of power assist may be due to low engine vacuum, a leaky vacuum hose to the brake booster, or a defective brake booster. The booster is located between the master brake cylinder and firewall in the engine compartment. Sometimes a faulty check valve will allow vacuum to bleed out of the booster causing a hard pedal when the brakes are applied. This condition can be diagnosed by starting the engine (to build vacuum), shutting it off, waiting four or five minutes, then trying the brakes to see if there is power assist. No assist means a new check valve is needed.

A quick way to check the vacuum booster is to pump the brake pedal several times with the engine off to bleed off any vacuum that may still be in the unit. Then hold your foot on the pedal and start the engine. If the booster is working, the amount of effort required to hold the pedal should drop and the pedal itself may depress slightly. If nothing happens and the vacuum connections to the booster unit are okay, a new booster is needed (the vacuum hose should be replaced, too).

On vehicles equipped with “Hydroboost” power brakes, a hard pedal can be caused by a loose power steering pump belt, a low fluid level, leaks in the power hoses, or leaks or faulty valves in the hydroboost unit itself (the latter call for rebuilding or replacing the booster).

On vehicles that use the ABS pump to generate brake boost, a problem with the ABS pump or high pressure accumulator can cause a loss of power assist. This will usually cause the ABS WARNING LIGHT to come on. The ABS system will also set a fault code that corresponds to the problem, which requires a scan tool to read.

More Information About Silencing Disc Brake Squeal

Like fingernails scraping across a blackboard, disc brake squeal is enough to make anybody’s hair stand on end. For some neurological reason that is not fully understood, human beings react negatively to high-pitched squeals like crying babies, sirens and screeching breaks. So if your brakes are squealing, you want the noise to go away.

Brake squealing is produced by high-frequency vibration in the brakes. With disc brakes, vibrations can occur between the pads and rotors; the pads and calipers; the calipers and mounts; and/or within the rotors themselves. With drum brakes, the vibrations can originate between the shoes and the backing plates, and/or within the drums.

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The noise is not dangerous as long as there is no metal-to-metal contact, the brakes are working properly and there is adequate lining thickness. But, it sure can be annoying. So, to get rid of it, you first have to figure out what is causing the brake noise.

DISC BRAKE SQUEAL

Complaints about brake squeal became a problem when front-wheel drive and semi-metallic brakes arrived on the scene in the 1980s. Semi-metallic pads are harder than their asbestos counterparts, and thus are more apt to chatter and squeal if there are any irregularities or roughness on the rotor surface, or if you notice looseness between the pads and calipers.

Some types of caliper designs are more apt to be noisy than others. The pads in these calipers may not be held as tightly and/or the caliper itself may move around a lot when the brakes are applied. And, as we said earlier, the greater the play in the system, the greater the tendency to make noise. That’s why some new car dealers try to dismiss the problem by telling their customers some noise is “normal”, leaving the customer no alternative but to live with the problem or to get it fixed by somebody else.

Trying to fix a squeal problem the wrong way can often make the problem worse. If somebody does a quick brake job and replaces the brake pads but doe snot resurface the rotors, the result can be an even louder squeal. The same can happen if the rotors are resurfaced incorrectly, too quickly or with dull tools. Excessive rotor runout can also cause problems.

DRUM BRAKE NOISE

One of the leading causes of brake squeal in drum brakes is poor contact between the shoes and drum. Heel and toe contact between the shoe and drum is often the culprit, and the cure is to either replace the shoes with new ones or to resurface the drum slightly to increase its inside diameter. New shoes are ground with a slight eccentric to compensate for drum wear.

This moves the point of contact away from the ends of the shoes toward the middle. In the old days, mechanics used to arc shoes to match their shape to the drum. But, with the concerns about asbestos, shoe grinding is pretty much a thing of the past (although some say it will make a comeback as more and more new cars switch to non-asbestos linings on their drum brakes).

INSPECTING THE BRAKES

 

    • Open the hood, and check the brake fluid level and its appearance. A low level may indicate a leak or worn linings. Discoloration indicates moisture contamination and the need for a fluid change. An electronic tester or chemical test strips can be used to check the level of moisture contamination in the fluid.
    • Apply the brakes, and start the engine. Does the pedal drop slightly? It should because it indicates a good vacuum booster. No boost may indicate a leaky booster diaphragm or vacuum connection. How does the brake pedal feel? Is it firm? A soft or mushy-feeling pedal usually indicates air in the lines or leaks. A pedal that slowly sinks is a classic symptom of a worn master cylinder. Is the amount of pedal travel normal? A low pedal may indicate worn linings, the need for adjustment, defective/frozen drum brake adjusters or a low fluid level. Do the brake lights come on when you step on the pedal? No lights may indicate a defective or misadjusted brake light pedal switch or burned out bulbs in the tail lights.
    • On ABS-equipped vehicles, turn the ignition on to verify that the ABS warning light circuit works. The ABS light should come on for a few seconds, then go out if everything is fine. No light? Then you have found a bulb that needs replacing or a wiring problem. If the light comes on and remains on (does not go out), then further diagnosis will be required to find out what’s wrong with the ABS system. On some ABS systems, faults may have occurred that may not be serious enough to cause a continuous ABS warning light. These may be stored in the ABS module memory as “non-latching” or “soft” fault codes. Don’t ignore ABS codes because they may be a clue that more serious problems will be forthcoming.
    • Apply the parking brake. Does the pedal or handle work smoothly? Is it adjusted properly? Does the brake light come on? No brake warning light may indicate a bad bulb or defective or misadjusted parking brake switch. Does the parking brake hold the vehicle? Put the transmission into gear with the parking brake applied. If it fails to hold the vehicle, it needs adjusting. Now release the parking brake. Failure to release fully means the linkage, cables or locking mechanisms need attention.
    • Take a short test drive. DO NOT drive the vehicle if the brakes have failed, if there is insufficient pedal travel or firmness to stop the vehicle safely, or there is a serious fluid leak. While driving, apply the brakes several times to check for noise, pull to either side or grabbing. Also check for drag when the brakes are released. Note pedal feel, especially any pulsation that would indicate warped rotors. If possible, do a panic stop to check for ABS operation.

 

    • Remove a front wheel and measure the thickness of the brake pads. If worn down to minimum specifications or if wear indicators are making contact with the rotor, new linings are needed. If the pads are still above specs, they should probably be replaced anyway if they are near the end of their service life or if they are noisy. Also, note the condition of the rotors. Deep scratches or grooves indicate a need for resurfacing. Measure runout and parallelism, too. If out of specs, resurfacing or replacement is needed. Are there discolored spots, heat cracks or warpage? These symptoms may also indicate a need for rotor resurfacing or replacement.
    • Note the condition of the calipers and caliper mounts. Also note whether or not the pads are worn evenly. Uneven pad wear can be caused by corrosion on the caliper mounting guides or keyway.
    • Pull a drum, and inspect the drum surface, brake shoes, hardware and wheel cylinder. If the shoe linings are at or below minimum specifications, new shoes are needed. If the linings are still above minimum specs but are getting thin, new shoes are recommended to extend the life of the brakes.

Find & Fix Coolant Leaks

Coolant leaks can occur anywhere in the cooling system. Nine out of ten times, coolant leaks are easy to find because the coolant can be seen dripping, spraying, seeping or bubbling from the leaky component. The first symptom of trouble is usually engine overheating. But your car may also have a Low Coolant indicator lamp. If you suspect your vehicle has a coolant leak, open the hood and visually inspect the engine and cooling system for any sign of liquid leaking from the engine, radiator or hoses. The color of the coolant may be green, orange or yellow depending on the type of antifreeze in the system. You may also notice a sweet smell, which is a characteristic odor of ethylene glycol antifreeze.

The most common places where coolant may be leaking are:

Water pump — A bad shaft seal will allow coolant to dribble out of the vent hole just under the water pump pulley shaft. If the water pump is a two-piece unit with a backing plate, the gasket between the housing and back cover may be leaking. The gasket or o-ring that seals the pump to the engine front cover on cover-mounted water pumps can also leak coolant. Look for stains, discoloration or liquid coolant on the outside of the water pump or engine.

Radiator — Radiators can develop leaks around upper or loser hose connections as a result of vibration. The seams where the core is mated to the end tanks is another place where leaks frequently develop, especially on aluminum radiators with plastic end tanks. On copper/brass radiators, leaks typically occur where the cooling tubes in the core are connected or soldered to the core headers. The core itself is also vulnerable to stone damage. Internal corrosion caused by old coolant that has never been changed can also eat through the metal in the radiator, causing it to leak.

Most cooling systems today are designed to operate at 8 to 14 psi. If the radiator can’t hold pressure, your engine will overheat and lose coolant.

Hoses — Cracks, pinholes or splits in a radiator hose or heater hose will leak coolant. A hose leak will usually send a stream of hot coolant spraying out of the hose. A corroded hose connection or a loose or damaged hose clamp may also allow coolant to leak from the end of a hose. Sometimes the leak may only occur once the hose gets hot and the pinhole or crack opens up.

Freeze plugs — These are the casting plugs or expansion plugs in the sides of the engine block and/or cylinder head. The flat steel plugs corroded from the inside out, and may develop leaks that are hard to see because of the plug’s location behind the exhaust manifold, engine mount or other engine accessories. On V6 and V8 blocks, the plugs are most easily inspected from underneath the vehicle.

Heater Core — The heater core is located inside the heating ventilation and air conditioning (HVAC) unit under the dash. It is out of sight so you cannot see a leak directly. But if the heater core is leaking (or a hose connection to the heater core is leaking), coolant will be seeping out of the bottom of the HVAC unit and dripping on the floor inside the passenger compartment. Look for stains or wet spots on the bottom of the plastic HVAC case, or on the passenger side floor. Some Chrysler vehicles have a reputation for developing coolant leaks in the heater core, and repeat heater core failures. Some have found that an aftermarket copper/brass replacement heater core lasts longer in these applications than the original equipment aluminum heater core.

Intake Manifold gasket — The gasket that seals the intake manifold to the cylinder heads may leak and allow coolant to enter the intake port, crankcase or dribble down the outside of the engine. Some engines such as General Motors 3.1L and 3.4L V6 engines as well as 4.3L, 5.0L and 5.7L V8s are notorious for leaky intake manifold gaskets. The intake manifold gaskets on these engines are plastic and often fail at 50,000 to 80,000 miles. Other troublesome applications include the intake manifold gaskets on Buick 3800 V6 and Ford 4.0L V6 engines.

INTERNAL COOLANT LEAKS

There are the worst kind of coolant leaks for two reasons. One is that they are impossible to see because they are hidden inside the engine. The other is that internal coolant leaks can be very expensive to repair.

Bad head gasket –Internal coolant leaks are most often due to a bad head gasket. The head gasket may leak coolant into a cylinder, or into the crankcase. Coolant leaks into the crankcase dilute the oil and can damage the bearings in your engine. A head gasket leaking coolant into a cylinder can foul the spark plug, and create a lot of white smoke in the exhaust. Adding sealer to the cooling system may plug the leak if it is not too bad, but eventually the head gasket will have to be replaced.

If you suspect a head gasket leak, have the cooling system pressure tested. If it fails to hold pressure, there is an internal leak. A “block tester” can also be used to diagnose a leaky head gasket. This device draws air from the cooling system into a chamber that contains a special blue colored leak detection liquid. Combustion gases will react with the liquid and cause it to change color from blue to green if the head gasket is leaking.

Head gasket failures are often the result of engine overheating (which may have occurred because of a coolant leak elsewhere in the cooling system, a bad thermostat, or an electric cooling fan not working). When the engine overheats, thermal expansion can crush and damage portions of the head gasket. This damaged areas may then start to leak combustion pressure and/or coolant.

Cracked Head or Block — Internal coolant leaks can also occur if the cylinder head or engine block has a crack in a cooling jacket. A combustion chamber leak in the cylinder head or block will leak coolant into the cylinder. This dilutes the oil on the cylinder walls and can damage the piston and rings. If the coolant contains silicates (conventional green antifreeze), it can also foul the oxygen sensor and catalytic converter. If enough coolant leaks into the cylinder (as when the engine is sitting overnight), it may even hydro-lock the engine and prevent it from cranking when you try to start it. Internal leaks such as these can be diagnosed by pressure testing the cooling system or using a block checker.

A coolant leak into the crankcase is also bad news because it can damage the bearings. Coolant leaking into the crankcase will make the oil level on the dipstick appear to be higher than normal. The oil may also appear frothy, muddy or discolored because of the coolant contamination.

Leaky ATF oil cooler — Internal coolant leakage can also occur in the automatic transmission fluid oil cooler inside the radiator. On most vehicles with automatic transmissions, ATF is routed through an oil cooler inside the radiator. If the tubing leaks, coolant can enter the transmission lines, contaminate the fluid and ruin the transmission. Red or brown drops of oil in the coolant would be a symptom of such a leak. Because the oil cooler is inside the radiator, the radiator must be replaced to eliminate the problem. The transmission fluid should also be changed.

PRESSURE TESTING THE COOLING SYSTEM FOR LEAKS

There are several ways to find out whether or not your cooling system is holding pressure. One is to top off your cooling system, tighten the radiator cap and start the engine. When the engine reaches normal operating temperature, turn on the air conditioner (to increase the cooling load on the system) and/or take it for a short drive. Then check the radiator, hoses and water pump for seepage or leaks.

WARNING: DO NOT open the radiator cap while the engine is hot! Even if the cooling system is leaking, the coolant will be under considerable pressure — especially if it is low and coolant is boiling inside the engine. Shut the engine off and let it sit about an hour so it can cool down. Then place a rag over the radiator cap and slowly turn the cap until it starts to release pressure. Wait until all the pressure has vented before turning the cap the rest of the way off.

A special tool called a pressure tester can also be used to check your cooling system. The tool is nothing more than a little hand pump with a combination vacuum-pressure gauge and a fitting that is attached to the radiator filler neck. To check for leaks, attach the tool to the radiator and pressurize the radiator to the pressure rating on the radiator cap. For example, if you have a radiator cap that says 12 pounds, you pressurize the radiator to 12 lbs. and wait to see what happens. If there are no leaks, the system should hold pressure for 10 to 15 minutes. If it does not hold pressure, the system is leaking. If you cannot see any visible leaks on the outside, it means the leak is inside (bad head gasket or cracked head or block). See How to Fix a Leaky Head Gasket.

A block Checker is another tool that can be used to detect a leaky head gasket. The gas-sensitive blue liquid changes color if there are any combustion gases in the coolant.

Leak detection dye can also be added to the coolant itself to make a slow leak easier to find. Some of these dyes glow bright green or yellow when exposed to ultraviolet light.

RADIATOR CAP CHECKS

The radiator cap should also be pressure tested, especially if the system has been overheating or losing coolant with no obvious external leaks. A weak cap that cannot hold pressure will allow the system to boil over. If the cap cannot hold its rated pressure, replace it.

REPAIRING A LEAKY RADIATOR

If your radiator is leaking, you have several repair options:

You can try the cheap fix and add a bottle of cooling system sealer to the radiator. These products are designed to seal small leaks. They can also seal internal engine leaks. Some work better than others, but most provide only a temporary solution to your problem.

You can attempt to repair the radiator yourself. Copper/brass radiators on older vehicles can often be soldered to repair leaks. Cracks or pinholes in aluminum radiators in newer vehicles can often be repaired with epoxy glue. But if the core is severely corroded or damaged, the radiator may have to be professionally repaired at a radiator shop, or replaced with a new radiator.

HOW TO FIX A LEAKY HEATER CORE

As with a leaky radiator, you might try the cheapest fix and add a bottle of cooling system sealer to see if that will stop the leak. If the leak is small, the sealer will probably stop the leak – at least temporarily. But if the sealer does not stop the leak, you will have to disassemble the HVAC case to replace the heater core. This is a very time-consuming and difficult job that involves a LOT of labor on most vehicles. The labor to replace a heater core can often run 8 to 10 hours or more!

Some vehicles have had problems with repeat heater core failures (some Chrysler cars, for example). The problem in some cases is the design of the heater core itself, or the metal alloys from which it was made. But a common cause of heater core leaks is Electrolysis Corrosion. One fix is to attach a grounding strap on the heater core. Another is to replace an original equipment aluminum heater core with an aftermarket copper/brass heater core.

COOLANT RESERVOIR LEAKS

Another cooling system component that sometimes needs attention is the coolant overflow reservoir. The coolant overflow reservoir does more than catch the overflow from the radiator. It serves as a storage tank for excess coolant. When the system is hot, coolant will be forced out through the radiator pressure cap and into the reservoir. Then as the system cools down, decreasing pressure will draw coolant back into the radiator.

On many newer vehicles, the coolant reservoir is pressurized and is an integral part of the cooling system. The filler cap for the cooling system is located on the reservoir tank, and the tank is connected to the radiator and engine with hoses. The reservoir is transparent plastic and you can see the coolant level inside.

If the coolant reservoir is cracked or leaking, the system may lose coolant every time the engine heats up. Eventually, this can cause the engine to overheat.

Small punctures or cracks in the overflow reservoir can usually be repaired with silicone sealer. If the reservoir needs to be replaced, make sure the hoses are routed correctly between the radiator and the reservoir, and that it is free from kinks that could block the flow of coolant back and forth.

HOW TO FIX A LEAKY FREEZE PLUG

Freeze plus (also called expansion plugs) are round metal plugs that are pressed into cylinder head and engine block castings. The plug is supposed to push out and save the casting if the coolant does not contain enough antifreeze to prevent it from freezing during cold weather. Over time, the plugs can corrode from the inside and leak, causing the engine to lose coolant and overheat.

One way to temporarily patch a leaky freeze plug is to clean the surface of the plug, sand it lightly with sandpaper, and pack it solid with a high temperature two-part epoxy such as gas tank sealer or JB Weld epoxy. Let it cure overnight. This trick usually seals leaky expansion plugs that would otherwise be very difficult to replace.

To replace a leaky freeze plug, use a hammer and drift to knock out the old plug. Pounding in on one side of the plug will usually cause it to twist. The plug can then be pried out with a large screwdriver. Clean the hole, then apply a liberal coating of sealer to the hole and carefully drive in a new replacement plug. The plug must go in straight or it may not seal.

Another repair option is to replace a solid metal freeze plug with an expandable freeze plug. The expandable plugs have a rubber grommet that expands and seals against the opening when the center bolt in the plug is tightened. It’s easier to install and less apt to leak than a solid plug.

HOW TO FIX A LEAKY COOLANT HOSE

Do not waste your time trying to patch or wrap a leaky radiator or heater hose. Sealers and Stop Leak products also do not work well with hoses. Replace the bad hose with a new one, and inspect all the other hoses because if one has failed the others are probably reaching the end of the road, too.

Old hoses are often hard and stick to their fittings, making them difficult to remove. Use a razor blade or box cutter to slit the old hose so it can be easily pulled off its end fittings.

It is also a good idea to replace the original hose clamps, especially if they are the ring type. Ring clamps can lose tension with age and may not hold the hose tightly. Worm drive stainless steel clamps are best. But quality brand stainless steel worn drive clamps, not the cheap plain steel ones that are made in China. They will rust and fail.

You should also inspect the inside of your old radiator and heater hoses after they have been removed to check for deep fissures or cracks caused by Electrolysis Corrosion. This type of corrosion can be caused by old antifreeze that no longer provides adequate corrosion protection, or by stray electrical currents that use the coolant as a ground path.

HOW TO FIX A LEAKY WATER PUMP

No Stop Leak or cooling system sealer product will seal a water pump that is leaking coolant past the shaft seal. Replacement is your only option. But you can save some money on the job by using a remanufactured water pump rather than a new water pump.

Replacing a water pump is not too hard a job on most engines, but on some it can be tricky. On some engines (2.8L GM V6 engines, for example), the bolts that hold the water pump also hold the timing cover in place. If you are not careful, the timing cover seal can be broken allowing coolant to leak into the crankcase. GM recommends using a special tool (J-29176 or equivalent) to hold the timing cover tight while the pump is being changed.

If your engine has a belt-driven fan with a fan clutch, it is also a good idea to check the fan clutch when replacing the water pump. The lifespan of both is about the same, so the fan clutch may also need be replaced. If the clutch is leaking silicone fluid, or has any wobble in the bearing, it must be replaced.

REFILLING THE COOLING SYSTEM

When refilling the cooling system after making a repair, always use a 50/50 mixture of antifreeze and water. Never use straight water because it has no freezing protection, no corrosion protection and it boils at a lower temperature (212 degrees F.) than a mixture of antifreeze and water (which protects to 240 degrees F.).

Use the type of antifreeze specified by the vehicle manufacturer, or a Universal Coolant that is compatible with all makes/models. Most late model vehicles require some type of OAT or HOAT long life coolant. GM vehicles use Dex-Cool.

On some late model front-wheel drive cars, refilling the cooling system can be tricky unless you “burp” the system by opening a bleeder vent or cracking a hose at a high point in the system to allow trapped air to escape. If you do not get all of the air out, the engine may overheat the first time you drive it.