AUTOMOTIVE DIAGRAMS
Engine The engine is a mechanical device designed to convert chemical energy (fuel) into kinetic energy (motion), which powers your vehicle. Almost all vehicles (including hybrids) use internal combustion engines that burn fuel. In an internal combustion engine, air and fuel are ignited inside a cylinder and the pressure that is created forces pistons to move up and down. This rotates the crankshaft, which del ivers power to the wheels via the drivetrain.
Piston
A piston is a cylindrical piece of metal that moves up and d own inside each cylinder, compressing the air-fuel mixture and capturing the force created by the combustion process. This force is then transferred to the crankshaft, crankshaft, via the connecting connecting rod. More >>
Crankshaft
The crankshaft is a long, steel shaft that transfers the up-and-down motion of the pistons and connecting rods into rotational motion. More >>
Related Systems
Ignition System The ignition system supplies the "spark" to each cylinder, which is necessary to begin the combustion process. Ignition systems have evolved from using a mechanical distributor and special wires to transmit the spark from the ignition coil to each spark plug, to a fully electronic system which has an ignition coil mounted directly on top of each spark plug. Routine maintenance has been reduced from a "tuneup" every 12,000 miles to simply replacing the spark plugs every 100,000 miles.
Fuel System The fuel system provides the fuel necessary for the engine to operate. In years past, a mechanical fuel pump and carburetor were used. In order for engines to run better and produce less harmful emissions, electronic fuel injection systems have taken their place. On modern vehicles, fuel is supplied by an electric pump and metered to the cylinders by computer controlled fuel injectors.
Crankshaft
The crankshaft is a long, steel shaft that transfers the up-and-down motion of the pistons and connecting rods into rotational motion. More >>
Related Systems
Ignition System The ignition system supplies the "spark" to each cylinder, which is necessary to begin the combustion process. Ignition systems have evolved from using a mechanical distributor and special wires to transmit the spark from the ignition coil to each spark plug, to a fully electronic system which has an ignition coil mounted directly on top of each spark plug. Routine maintenance has been reduced from a "tuneup" every 12,000 miles to simply replacing the spark plugs every 100,000 miles.
Fuel System The fuel system provides the fuel necessary for the engine to operate. In years past, a mechanical fuel pump and carburetor were used. In order for engines to run better and produce less harmful emissions, electronic fuel injection systems have taken their place. On modern vehicles, fuel is supplied by an electric pump and metered to the cylinders by computer controlled fuel injectors.
Engine Cooling System The cooling system helps regulate the amount of heat in the engine. If it’s to o hot, the engine can overheat. If it’s too col cold, d, the engine emits more pollutants and engine components components prematurely wear wear out. If the cooling system fails to keep the engine at the right temperature, temperature, it can suffer suffer significant damage and, in some cases, fail entirely.
Air Filter In order to run, the engine needs a precise mixture of fuel and air. When outside air is d rawn into the engine, the air filter prevents harmful dirt and debris from entering the system. Symptoms of Wear or Failure
Poor gas mileage
Reduced engine power Related Repair Advice
The air filter should be inspected, cleaned, and/or replaced every 12,000 to 15,000 miles
When replacing the air filter, dirt and debris should be removed from the air filter housing
If oil has contaminated the air filter, it should b e replaced; oil contamination may indicate a problem with the PCV system
Air filters will need to be replaced more often in vehicles driven in dust y and sandy areas
Coolant Coolant is the fluid that flows through the engine’s cooling system. Its main pu rpose is to transfer heat generated by the en gine to the radiator so the engine doesn’t overheat. Symptoms of Wear or Failure
Temperature gauge may read very high
Engine overheating
Low coolant warning light may illuminate
Dirty or smelly coolant indicates that a system flush may be needed Related Repair Advice
Over time, coolant gets dirty and breaks down; it should be replaced following the manufacturer's recommendation
Make sure to use the coolant the manufacturer recommends; the wrong coolant can damage your vehicle
A pressure check of the cooling system should be performed to determine where a coolant leak is originating. After repairs, the system should be pressure tested again again to verify that the repair is successful. successful.
If you have a pro blem with the coolant level dropping, but no signs of an external leak, the issue may be an internal engine leak. This type of leak may be due to a leaking intake manifold gasket, head gasket, or oil cooler. A shop will need to conduct various tests to find these types of leaks.
After the cooling system has been serviced or repaired, it's important to verify that the system is no t leaking, the radiator fans are op erating properly, and all air bubbles and air pockets are bled from the cooling system.
To help prevent future issues, we recommend replacing the thermostat when the cooling system has been opened for repairs (e.g. water pump or radiator replacement) or during a system flush
Crankshaft The crankshaft is a long, steel shaft that transfers the up-and-down motion of the pistons and connecting rods into rotational motion. Symptoms of Wear or Failure
Knocking noise from engine
Low engine oil pressure Related Repair Advice
If a crankshaft or connecting rod b earing fails, the crankshaft should be thoroughly inspected before reuse
In some cases, a failed crankshaft can be repaired or replaced. However, on higher mileage vehicles, engine replacement is often recommended.
Camshaft Driven by the crankshaft, the camshaft has multiple elliptical lobes (cams), one for each intake and exhaust valve contained in the engine. As the camshaft rotates, the lobes regulate the opening and closing of the valves. Symptoms of Wear or Failure
Abnormal noise from the valve train
Engine misfires Related Repair Advice
The camshaft oil seals should be inspected and replaced as n ecessary when the timing belt is replaced
Crankcase Mounted between the engine block and the oil pan, the crankcase supports the crankshaft, allowing it to spin freely while transmitting power (torque) from the engine. Symptoms of Wear or Failure
Engine oil leak
Knocking noise from engine Related Repair Advice
Engine-specific oil sealing procedures must be employed when installing the crankcase
Cylinder Head Mounted to the top of the engine b lock, the cylinder head houses the intake and exhaust valves, as well as the spark p lugs. Symptoms of Wear or Failure
Engine misfire
Engine overheating
Excessive oil consumption Related Repair Advice
The cylinder head mounting surface should be thoroughly inspected when replacing the head gasket
To avoid damage to the cylinder head, manufacturer's recommendations should be followed when removing sp ark plugs from an aluminum cylinder head
Drive Belt/Fan Belt These belts can be used individually or grouped together as p art of the belt/pulley system that is driven by the engine crank shaft to run such items as the air conditioning compressor, alternator, and power steering pump. Symptoms of Wear or Failure
Belts may become dry, cracked, or glazed
Belts may emit a chirping or squeaking sound Related Repair Advice
On older vehicles, belts with a “V" profile were the unive rsal drive belt design, but more modern vehicles use the flat "ribbed" design
The term "serpentine belt" referrers to a ribbed belt that d rives multiple accessories.
For optimal performance and reliability, belts should be replaced at the interval recommended by the manufacturer. We recommend replacing all of the drive belts as a set, so that they wear evenly.
We recommend replacing drive belts if related components are being repaired and the belts have signs of wear or have over 30, 000 miles on them
High-quality drive belts are less likely to squeak and/or prematurely fail
Leaking valve cover gaskets can cause p remature drive belt failure. Engine oil will damage even a new belt.
A water pump will require replacement if it begins to leak coolant or b ecome noisy. Leaking coolant can damage the drive and timing belts.
Engine Block The engine block is the main body of the engine assembly. It contains the cylinders that accommodate pistons and connecting rods. Symptoms of Wear or Failure
Abnormal knocking or rattling noise
Engine oil leak Related Repair Advice
Engine replacement is often recommend when problems are encountered with the engine block
A "short b lock" replacement may also be recommended — this replacement only includes the lower parts of the engine and leaves out the cylinder head and intake manifold
Engine Cylinder Engine cylinders are machined round bores (tubes) inside the engine block that house the pistons. As the engine operates, the pistons move u p and down within the cylinders. Symptoms of Wear or Failure
Engine misfire
Excessive oil consumption
Engine overheating Related Repair Advice
Engine replacement is often recommend when p roblems are encountered with a cylinder
A "short b lock" replacement may also be recommended — this replacement only includes the lower parts of the engine and leaves out the cylinder head and intake manifold
The cylinders may be machined inserts (sleeves) that are fit into the engine block or cast and machined as an integral part of the engine block
Head Gasket The head gasket creates a working seal between the cylinder head and the engine block. Symptoms of Wear or Failure
Check Engine Light may illuminate
Engine runs roughly when first started
Engine overheating
White, sweet smelling smoke from exhaust
Coolant or oil leak Related Repair Advice
Head gasket failures are often due to an overheated engine, but can also be caused by high mileage and/or age
If the head gasket(s) is replaced, the cylinder head(s) will need to be inspected and machined. Additional repairs may be needed after the inspection, which can add several hundred dollars to the repair.
To prevent an expensive, recurring problem, the integrity of the entire cooling system should be inspected and tested when a head gasket is replaced. Due to the damaging effects of coolant entering the combustion chamber, oxygen sensor and/or catalytic converter replacement may be prud ent or even necessary. This is especially true if head gasket failure was severe or prolonged.
Lower Radiator Hose After the radiator has cooled the coolant, the lower radiator hose carries it from the radiator back to the engine. Symptoms of Wear or Failure
Coolant leak
Temperature gauge may run high
Engine overheating Related Repair Advice
Radiator hoses, like all hoses, should be checked periodically for cracks and swelling. Being constructed of rubber, they are suscepti ble to dry rot and cracking as they age, and also deteriorate when they come into contact with oil.
The entire cooling system should be inspected when replacing coolant hoses. If any other hoses or cooling system parts show signs of wear, they should be replaced at this time.
We recommend replacing the hose clamps when the hoses are replaced, as the clamps will weaken over time and new clamps will help prevent coolant leaks
To help prevent future issues, we recommend replacing the thermostat when the cooling system has been opened for repairs (e.g. water pump or radiator replacement) or during a system flush
Upper Radiator Hose The upper radiator hose carries hot coolant from the engine into the radiator for cooling. Symptoms of Wear or Failure
Coolant leak
Temperature gauge may run high
Engine overheating Related Repair Advice
As hot engine coolant leaves the thermostat housing, it first contacts the upper radiator hose. This added stress makes the upper radiator hose the most common coolant hose to fail.
Radiator hoses, like all hoses, should be checked periodically for cracks and swelling. Being constructed of rubber, t hey are susceptible to dry rot and cracking as they age. They also deteriorate when they come into contact with oil.
The entire cooling system should be inspected when replacing coolant hoses. If any other hoses or cooling system parts show s igns of wear, they should be replaced at this time.
We recommend replacing the hose clamps when the hoses are replaced, as the clamps will weaken over time and new clamps will h elp prevent coolant leaks
To help prevent future issues, we recommend replacing the thermostat when the cooling system has been o pened for repairs (e.g. water pump or radiator replacement) or during a system flush
Oil Filter The engine oil filter removes contaminants from the engine oil before it circulates throughout the engine. Symptoms of Wear or Failure
Abnormal knocking noise from engine
Engine oil leak Related Repair Advice
Manufacturers differ in their recommended guidelines for when engine oil and oil filters should be changed. As a general rule, however, engine o il should be changed every 3,000 miles to keep the engine healthy and to prolong its life.
We recommend using a high-quality engine oil filter. Cheap filters wear more quickly and may not prop erly keep contaminants out of the engine.
We recommend replacing the drain plug gasket along with the oil and oil filter
Oil Pan Mounted to the bottom of the crankcase, the oil pan is a reservoir where engine oil is stored and drawn from. Symptoms of Wear or Failure
Oil may leak onto the ground and be seen on the underside of the vehicle Related Repair Advice
The oil pan is sealed with a gasket, which can be made of paper, rubber, or a sealing liquid (liquid gasket)
Some engines have an upper and lower oil pan gasket; the upper oil pan may also be referred to as the crankcase
The oil pan is on the bottom of the engine, so any oil leaks from the top or front of the engine could drain down and look like an oil pan leak. It's important to verify that there are no other leaks before having the oil pan resealed.
Over-tightening of the oil drain plug can d amage the oil pan threads, requiring replacement of the oil pan
Oil Pan Gasket The oil pan gasket is the working seal between the o il pan and the lower part of the engine. Symptoms of Wear or Failure
Engine oil leak Related Repair Advice
The oil pan gasket can be made of paper, rubber, or a sealing liquid (liquid gasket)
Some engines have an upper and lower oil pan gasket; the upper oil pan may also be referred to as the crankcase
The oil pan is on the bottom of the engine, so any o il leaks from the top or fron t of the engine could drain down and look like an oil pan leak. It's important to verify that there are no other leaks before having the oil pan resealed.
Oil Drain Plug Gasket The oil drain plug gasket seals the oil drain p lug where it connects to the oil pan. Symptoms of Wear or Failure
Engine oil leak Related Repair Advice
The oil drain plug gasket is commonly inspected and replaced when the engine o il is changed
Oil Pump The oil pump creates the pressure necessary to circulate oil throughout the engine. Symptoms of Wear or Failure
Oil light may come on or engine oil p ressure gauge will read low
The engine may make loud clicking or knocking no ises Related Repair Advice
Low oil pressure can be caused by u sing the incorrect type of engine oil. Be sure to check with your owner's manual to ascertain the correct type for your engine and climate.
The oil pressure should be checked before condemning an o il pump. A good quality repair shop will perform an oil pressure check and record the readings on the repair order.
Low oil pressure can be caused by a plugged oil pick-up screen, leaking seals, or worn bearings in the engine. It is important that these items are inspected before replacing the oil pump.
If the oil pump is located in the engine oil pan, the pan must be removed to replace it
If the oil pump is d riven directly by the crankshaft, the accessory belts, timing cover, timing belt, and crankshaft pulley must be removed in order to access the oil pump
PCV Filter The positive crankcase ventilation (PCV) filter, or crankcase emission filter, is connected to the fresh air side of the PCV system. Its pu rpose is to filter outside air before it enters the engine crankcase. Symptoms of Wear or Failure
Accumulation of dirt on filter Related Repair Advice
PCV filters should be inspected whenever the PCV system or air filter is serviced
PCV Hose The positive crankcase ventilation (PCV) hose carries crankcase gases from the engine to the intake manifold, where they are drawn into the cylinders for combustion. Symptoms of Wear or Failure
Engine vacuum leak
Rough or high engine idle
Illumination of the Check Engine Light Related Repair Advice
The PCV hose should be inspected whenever the PCV system is serviced
PCV Valve
The positive crankcase ventilation (PCV) valve controls the pressure of accumulating gases in the engine crankcase by venting them back into the intake manifold. Symptoms of Wear or Failure
Engine may run rough or stall
Excessive oil consumption
Engine oil leak
High emission levels
Check Engine Light may illuminate Related Repair Advice
The PCV valve should be replaced every 30,000 to 50,000 miles
The engine should be tested to verify normal operation after a P CV repair. This is to ensure that no additional problems exist that may have contributed to PCV failure.
A plugged PCV system can cause engine oil leaks. It's important that the shop checks and eliminates any issues with the PCV system while repairing engine oil leaks.
Piston A piston is a cylindrical piece of metal that moves up and d own inside each cylinder, compressing the air-fuel mixture and capturing the force created by the combustion process. This force is then transferred to the crankshaft, via the connecting rod. Symptoms of Wear or Failure
Engine misfire
Excessive oil consumption
Knocking or slapping noise from inside engine Related Repair Advice
A failed piston can cause internal engine damage; the engine might need to be replaced
A "short block" replacement may also be recommended — this replacement only includes the lower parts of the engine and leaves out the cylinder head and intake manifold
Radiator The radiator's job is to allow heat to be removed from the engine. As hot coolant passes through the radiator it is cooled before returning to the engine, where it absorbs heat and returns to the radiator. This cooling process keeps the engine from overheating. Symptoms of Wear or Failure
Coolant may leak or boil over
Temperature gauge may get really high
Illumination of the engine temperature warning light
Engine may run hot or overheat Related Repair Advice
We recommend replacing the thermostat and the radiator cap along with the radiator. The radiator hoses should also be replaced if they show signs of age or wear.
The entire cooling system should be inspected and tested when the radiator is replaced
Most radiators are made of metal and plastic. The plastic parts can become brittle and crack over time, leading to radiator replacement.
Removal of the front bumper, as well as removal of engine bay components such as hoses, ducting, and additional plumbing, are often required in the course of this repair
Radiator Fan Assembly The radiator fan assembly, which helps to cool the hot coolant in the radiator, is comprised of cooling fan(s), cooling fan motor(s), and a fan shroud. Symptoms of Wear or Failure
Fan may become noisy
Engine may overheat, especially when idling and driving in traffic
A/C may perform poorly, especially when idling and in stop -and-go traffic Related Repair Advice
If a new fan assembly is required, the engine may have been overheated and should be checked for damage before replacing the fan
If only some parts of the fan assembly are replaced, those that are not should be thoroug hly inspected to make sure they are still in good shape. If not, the parts should be replaced, too.
Radiator Cap The radiator cap seals the main filling point of the cooling system. It also allows a set pressure to build in the system, which increases the boiling point — and thus, the efficiency — of the cooling system. Symptoms of Wear or Failure
Coolant may leak or boil over
Temperature gauge may get really high
Illumination of the engine temperature warning light
Engine may run hot or overheat Related Repair Advice
The term "radiator cap" refers to the cap that regulates the coolant pressure in the cooling system. Standard pressure is usu ally 14 to 16psi.
The cooling may have multiple "radiator caps" located at the various fill points
Whenever the cooling system is serviced for any reason, the radiator cap(s) shou ld be inspected and replaced as necessary Be very cautious when removing the radiator cap. Don't remove the cap when the engine is hot.
Spark Plug The spark plug uses the energy prod uced by the ignition coil to generate the spark necessary to ignite the air/fuel mixture in the combustion chamber. Symptoms of Wear or Failure
Check Engine Light may come on or blink
Engine may run roughly
Abnormal engine noise due to loose or missing spark plug Related Repair Advice
Failing spark plugs can cause the engine to run r ough and misfire, which can trigger the Check Engine Light. Continuing to dr ive under these conditions can damage the catalytic converter.
Engines may have one or two spark plugs per cylinder and each spark plug can have from one to four electrodes
Replacing spark plugs can be labor intensive on some late model vehicles
To prevent ignition misfires and Check Engine Light problems, we recommend using only high -quality spark plugs, and preferably spark plugs from the OEM
Spark plugs have different ratings and it's important that the correct type are used
Spark plug terminals wear down over time and can lead to engine misfires. At a minimum, they need to be replaced at the mileage specified by th e vehicle manufacturer.
Manufacturer's instructions should be followed when removing spark plugs. Cylinder heads made from aluminum can be damaged if the correct procedures are not followed.
Thermostat The thermostat is a mechanical device that controls engine temperature. It blocks coolant flow to the radiator until the engine reaches a predetermined temperature. This allows the engine to warm up quickly and efficiently. Symptoms of Wear or Failure
Thermostat housing may leak coolant
Engine may overheat or never reach normal temperature
Higher exhaust emissions
Check Engine Light may illuminate
Poor fuel mileage Related Repair Advice
A high-quality OEM thermostat should be used. Poor quality thermostats may not function properly and can cause damage to the engine or components of the emission system.
We recommend replacing the thermostat any time major repairs are performed on the cooling system
Thermostat Gasket The thermostat gasket is a working seal between the thermostat housing and the engine. Symptoms of Wear or Failure
Thermostat housing may leak coolant
Engine may overheat Related Repair Advice
We recommend replacing the thermostat any time major repairs are performed on the cooling system
Throttle Body The throttle body is a housing containing a valve(s) that regulates the airflow entering the intake manifold on its way to the combustion chamber. The valve(s) opens and closes based on driver input via the gas pedal. Symptoms of Wear or Failure
Stalling problems
Engine may run roughly
Illumination of the Check Engine Light
Gas pedal hard to push as a result of a worn throttle shaft Related Repair Advice
Residue build up on the throttle bore can result in lower than normal engine idle and engine stalling, especially after battery replacement Newer vehicles are using an electronically-controlled throttle body in place of the older cable-operated system When replacing an electronic throttle body, the related connectors and wiring should be thoroughly inspected
Timing Belt The rubber timing belt connects the camshaft to the crankshaft of the engine. It helps the crankshaft drive the camshaft. Symptoms of Wear or Failure
Broken belt
Engine will stop running and internal engine damage can occur Worn or loose belt
Belt may "jump time" (skipping a tooth or more, usually on the cam gear). This results in a loss of synchronization and engin e performance.
Trouble codes from the camshaft or crankshaft sensors, causing Check Engine Light to illuminate
Slapping or scraping noises from engine Related Repair Advice
It is crucial that the timing belt be replaced at or before the interval recommended by the vehicle manufacturer. Failure to do so can result in a broken timing belt, which can turn off your engine and leave you stranded. It could also lead to severe engine damage.
Timing belts are used in lieu of timing chains in many engines. Since they are made ou t of rubber, they have a limited lifespan.
It is often recommended that you replace items like the water pump, front engine seals, drive belts, idlers, and tensioner along with the timing belt
Timing Chain The metal timing chain connects the camshaft to the crankshaft of the engine. It helps the crankshaft drive the camshaft. Symptoms of Wear or Failure
Engine may stall or run rough Noise in the front of the engine (a rattle or rumble, associated with engine speed) Check Engine Light may illuminate and set misfire, camshaft sensor, and crankshaft sensor codes Related Repair Advice
On certain engines, the water pump is driven by the timing chain. It should be replaced if the timing chain is replaced.
When replacing a timing chain, replace the whole timing chain set, which includes all of the chains, the gear set, the tensioner(s), and the guides
An engine may have multiple timing chains; replacing all of the chains and their related components is recommend if one chain re quires replacement
Using high quality, fully synthetic engine oil may extend the life of the timing chain and related components
Sometimes, a defective water pump, a loose or defective harmonic balancer, a defective drive belt tensioner, or a cracked flex plate can exhibit symptoms that may be misdiagnosed as a worn timing chain assembly
Timing Cover A timing cover is a metal or plastic enclosure that covers and pro tects the timing components from dirt, dust, and debris. Symptoms of Wear or Failure
Engine oil and/or coolant leak
Scraping or rattle noise from front of engine
Missing timing mark Related Repair Advice
When replacing the timing belt or chain, the timing cover should be inspected for d amage and replaced, if necessary
If the timing cover is removed to correct a leak, the timing components should be thoroughly inspected and replaced, if necessary
Timing Cover Gasket The timing cover gasket is the working seal between the timing cover and the engine block. Symptoms of Wear or Failure
Oil or coolant leak Related Repair Advice
The timing cover gasket may be made from standard gasket material, an O-ring style seal, or it may be sealed with a simple silicone-type sealant
If the timing cover is removed to correct a leak, the timing components should be thoroughly inspected and replaced, if necessary
Vacuum Pump The vacuum pump produces the vacuum power needed for vehicle functions such as braking and some HVAC functions. Symptoms of Wear or Failure
Brake pedal may be hard
Heating, ventilation, and AC (HVAC) system may malfunction
Abnormal noise Related Repair Advice
It's a good idea to u se a factory quality (OEM) vacuum pump. If the p ump is belt driven, replace the drive belt as well.
Components that rely on the vacuum pump (climate control and/or brake system components) may be incorrectly replaced if there is an issue with the vacuum pump
Vacuum pumps are used on Diesel engines (since they do not produce vacuum) and o n some gasoline engines that produce little vacuum, such as turbos
Valve Cover A valve cover is a metal or plastic covering that protects the valve train and camshaft(s) in each cylinder head. It keeps oil from leaking out into the engine compartment and debris from getting into the cylinder head. Symptoms of Wear or Failure
Engine oil leak
Burning smell due to oil on exhaust manifold Related Repair Advice
Many new vehicles use plastic valve covers. These can crack and cause an oil leak.
A leaking valve cover or gasket can drip oil all over the engine. In some cases, it's necessary to repair the valve cover lea k before any other oil leaks can be properly diagnosed.
Valve Cover Gasket Set The valve cover gasket set is the complete set of gaskets required to create the working seal between the valve cover(s) and the cylinder head(s). Symptoms of Wear or Failure
Engine oil may leak
Burning smell due to oil on the exhaust manifold
Engine misfire Related Repair Advice
Valve cover gaskets and seals need to be replaced when they begin to leak oil. This type of leak can damage other engine comp onents, especially belts, hoses, and spark plug wires.
Using high-quality valve cover gaskets will reduce the chance of recurring leaks and additional repairs
An engine misfire can result from oil leaking into the spark p lug tubes. The tube seals and valve cover gasket should always be replaced together.
When replacing the valve cover gasket, we recommend having a valve adjustment performed, if applicable. Since the valve cover is removed to adjust the valves, this will save in labor costs.
Water Pump The water pump, also known as the coo lant pump, circulates coolant through the engine’s cooling system. Symptoms of Wear or Failure
Noise from engine area, including a rumbling sound
Coolant leak
Engine overheating Related Repair Advice
When replacing the water pump, the drive belts may need to be removed. The belts should be replaced if they show signs o f wear.
The water pump may be driven by the timing belt or chain. It these cases, it is common to replace the water pump when the belt or chain is replaced.
Water pumps require replacement if they begin to leak coolant or become noisy. A leaking water pump can result in damage to th e drive and timing belts.
A failed water pump can be caused by pr oblems in the cooling system, such as a failing thermostat, radiator, or head gasket
The entire cooling system — including all of the coolant hoses and fittings, radiator, coolant fan(s), and fan clutch (if equipped) — should be inspected when replacing the water pump
To help prevent future issues, we recommend replacing the thermostat when the cooling system has been op ened for repairs (e.g. water pump or radiator replacement) or during a system flush
Most water pumps are either driven independently via their own belts or are driven by a serpentine belt that also drives many other components. Some current designs use the timing belt to drive the water pump. In these cases, it is advisable to replace the water pump in conjunction with scheduled timing belt replacement.
