Description: The cylinder block is a casting generally made out of iron or aluminum and holds the crankshaft, connecting rods, pistons and camshaft (cam-in-block, overhead valves only). The cylinder block has numerous machined surfaces to provide a precision fit to mating parts.
Purpose: The cylinder block serves as the main structural component of the engine and houses what’s commonly referred to as “the bottom end” (crankshaft, rods, pistons). The cylinder block is extremely strong so it can withstand the rigors of engine torque and vibration, while supporting all attached engine accessories and the transmission.
Maintenance Tips/Suggestions: The engine in your car will last for many thousands of miles if driven and cared for properly. The best way to care for the cylinder block is to follow a good maintenance regimen. This includes regular oil and filter changes, engine performance check-ups, and cooling system maintenance. If you notice that engine performance drops off, that the engine is using oil, or observe problems with coolant temperature or oil pressure, it’s wise to have these looked into as soon as possible by a qualified professional.
Description: A cylinder head is a casting generally made out of iron or aluminum that holds the valves, valve springs and retainers and one or two camshafts (overhead cam engines only). The cylinder head has numerous machined surfaces to provide a precision fit to mating parts. Inline four- and six-cylinder engines have one cylinder head. V6, V8, V10 and V12 engines have two cylinder heads.
Purpose: The cylinder head, when used with a head gasket, seals the cylinders so that they’re capable of building compression for engine operation.
Maintenance Tips/Suggestions: The engine in your car will last for many thousands of kilometers if driven and cared for properly. The best way to care for the cylinder head is to follow a good maintenance regimen. This includes regular oil and filter changes, engine performance check-ups, and cooling system maintenance. The main enemy of the cylinder head is overheating. If you notice that the engine temperature is higher than normal, take your car to a good repair shop as soon as possible. Overheating can quickly warp aluminum cylinder heads and contribute to head gasket failure. Any time you notice engine performance dropping off, or observe problems with coolant temperature or oil pressure, it’s wise to have these looked into as soon as possible by a qualified professional.
Valve Train Components
Description: The valve train typically includes the camshaft, valves, valve springs, retainers, rocker arms and shafts. On engines with traditional mounting of the camshaft in the cylinder block, the valve train also includes lifters and pushrods. Overhead cam engines may use more than one camshaft per cylinder head. Engines use different valve configurations, such as two, three, four or five valves per cylinder. These various valve arrangements are used for different engine breathing requirements. Some engines also use variable valve timing, which allows the engine to change breathing characteristics under different operating conditions.
Purpose: The cylinder head’s valves, when synchronized with the crankshaft of the cylinder block, allow the engine to “breathe”. In an engine, this means pulling the air and fuel mixture into the cylinder, then pushing the burned exhaust gases out. The better an engine breathes, the more efficient it becomes.
Maintenance Tips/Suggestions: To best care for the parts of the valve train, stick to a regular maintenance routine of oil and filter changes and proper cooling system care. Also check the owner’s manual to find out what the maintenance interval is for the timing belt (if equipped). If the timing belt breaks on some engines, it can cause major damage to the valve train and other parts of the engine.
Use the right gasoline for your car as recommended in the owner’s manual. In some cases, the use of premium fuel when it’s not needed can cause deposits on the intake valves, which can cause performance problems. Some symptoms of problems in the valve train include an engine that makes a ticking noise, runs rough, bucks, surges, stalls, gets poor fuel economy or fails an emissions test.
Gaskets & Sealing
Description: Gaskets and seals are usually named after their location or function on the engine. For example, a head gasket seals the cylinder head to the cylinder block. A rear main seal prevents the area around the rear crankshaft main bearing from leaking oil. Gaskets and seals can be made from a wide range of materials, many times specifically selected for the specific sealing task.
Purpose: Engine seals and gaskets prevent the leakage of oil, coolant and air between mating surfaces, internal passages and the outside of the engine. Seals and gaskets also prevent the entry of dirt and air into the engine.
Maintenance Tips/Suggestions: The best way to care for the gaskets and seals on your engine is to follow a regular maintenance regimen. This includes regular oil and filter changes, engine performance check-ups, and cooling system maintenance. Check your owner’s manual for positive crankcase ventilation (PCV) maintenance intervals and replace the valve as recommended. Oil leaks are one clue of a faulty PCV system. Overheating can quickly cause head gasket failure and warp aluminum cylinder heads. If telltale oil or coolant drips in your driveway or parking place are making you suspicious about a gasket or seal leak, have it investigated by a qualified service technician.
Description: Many of today’s engines use timing belts, but not all. Some engines still use a timing chain and sprocket arrangement. A timing belt is a precision component with teeth that mesh exactly with its mating sprockets. Especially critical is uniformity of the teeth and their spacing. The belt’s teeth are precision melded from a special rubber compound for good mesh and long life. The belt’s inherent tensile (stretch-resistant) qualities come from high strength cords that run parallel with the direction of belt travel.
Purpose: The timing belt maintains crankshaft-to-camshaft synchronization, keeping valve operation matched to piston position. On some engines, the belt also drives other components. These include the oil pump, water pump, and balance shafts.
Maintenance Tips/Suggestions: Check your car’s owner’s manual for information on timing belt maintenance. Manufacturers generally recommend a certain mileage for belt replacement. If the timing belt is not replaced at the suggested interval, the belt could break, leaving you stranded and possibly causing major engine damage. If you’re having the timing belt replaced, consider replacing other parts that may be accessed at the same time. The water pump, timing belt sprockets and tensioning pulleys are good examples.
Turbo & Supercharger
Description: A turbocharger uses an exhaust-gas driven turbine wheel, which drives a compressor wheel to boost air delivery to the engine. A supercharger uses mechanically driven rotors, usually from a belt, to boost air delivery to the engine.
Purpose: Turbochargers and superchargers enable increased burning of air and fuel by forcing more of it into the engine’s cylinders, thereby improving an engine’s breathing characteristics.
Maintenance Tips/Suggestions: Check your car’s owner’s manual for maintenance requirements of the turbocharger or supercharger. The turbocharger or supercharger on your car’s engine will last for many thousands of kilometers if cared for properly through a regular engine maintenance regimen. This includes regular oil and filter changes, engine performance check-ups, and cooling system maintenance. If you notice that engine performance drops off, that the engine is using oil, or notice other problems with coolant temperature or oil pressure, it’s wise to have these looked into as soon as possible by a qualified professional.