PISTON AS 2959688 - Caterpillar

Cylinder Block and Cylinder Head
The cylinder block has four cylinders which are arranged in-line. The cylinder block provides support for the full length of the dry cylinder liners. The cylinder liners are a press fitted part. The cylinder liners are pressed into the cylinder block. The cylinder liners have a flame ring above the flange.The cylinder block has five main bearings which support the crankshaft. Thrust washers on both sides of the center main bearing control the end play of the crankshaft.A cylinder head gasket is used between the engine block and the cylinder head in order to seal combustion gases, water, and oil.The engine has a cast iron cylinder head. An inlet valve and an exhaust valve for each cylinder are controlled by a pushrod valve system. The ports for the inlet and the exhaust valves are on the right side of the cylinder head.Pistons, Rings, and Connecting Rods
The pistons have a Fastram combustion chamber in the top of the piston in order to provide an efficient mix of fuel and air. The piston pin is off-center in order to reduce the noise level.The pistons have two compression rings and an oil control ring. The groove for the top ring has a hard metal insert in order to reduce wear of the groove. The skirt has a layer of graphite in order to reduce wear.The correct piston height is important in order to ensure that the piston does not contact the cylinder head. The correct piston height also ensures the efficient combustion of fuel which is necessary in order to conform to requirements for emissions.A piston and connecting rod are matched to each cylinder. The piston height is controlled by the length of the connecting rod. Seven different lengths of connecting rods are available in order to attain the correct piston height. The different lengths of connecting rods are made by machining the small end bearing off-center in order to form an eccentric bearing. The amount of the eccentricity of the bearing creates the different lengths of the connecting rods. Two heights of pistons are available in order to attain the correct piston height. The piston heights match specific lengths of pistons.Each cylinder has a piston cooling jet that is installed in the cylinder block. The piston cooling jet sprays engine oil onto the inner surface of the piston in order to cool the piston.Crankshaft
The crankshaft changes the combustion forces in the cylinder into usable rotating torque in order to power the engine. Vibration is caused by impacts from combustion along the crankshaft. The vibration forces are minimized by the use of a vibration damper. The vibration damper is located on the front of the crankshaft.A gear at the front of the crankshaft drives the timing gears. The crankshaft gear turns the idler gear which then turns the following gears:
the camshaft gear
the fuel injection pump
a lower idler gear which turns the gear of the lubricating oil pumpLip type seals are used on both the front of the