SOFTWARE GP-POWER TRAIN 2904774 - Caterpillar

Illustration 8 g03411247
(9) Injection Pump GearGovernor Gear
(10) Idler Gear
(11) Camshaft Gear
(12) Crankshaft Gear
(13) Oil pump drive gear The crankshaft is the hub around which other parts of the engine can be timed and driven. This is done by the meshing of gears as shown in the Illustration 8.The timing gears transmit torque from the crankshaft to the oil pump and injection pump and, at the same time, correctly control fuel injection to the cylinders and valve timing.Each gear has a mating mark inscribed on the gear for correct and easy assembly and is spherical with teeth set obliquely to the axis of rotation to rotate smoothly and reduce noise.Flywheel
Illustration 9 g03394119
(14) Crankshaft
(15) Flywheel Ring Gear
(16) Flywheel The flywheel (16) is made of heavy cast iron or steel and has gear teeth around the outer rim (15), which mesh with the drive pinion of starter.The flywheel mounted on the rear of the crankshaft (14) is a stabilizer for the whole engine.The flywheel stores the rotating force in the combustion stroke as inertial energy, reduces crankshaft rotating speed fluctuation and maintains the smooth rotating conditions.The flywheel periphery is inscribed with the marks showing fuel injection timing angle lines and top dead center mark "TC" for 1# piston.Rocker Arm
Illustration 10 g03394125
(17) Rocker Arm Shaft
(18) Rocker Arm
(19) Exhaust Valve
(20) Intake Valve
(21) Push Rod
(22) Adjusting Screw The rocker arms (18) are mounted on a rocker arm shaft (17) at the top of the engine.When the push rods (21) move up, the mating rocker arm is moved down, contacting the valve stem tip and opening the valve.These engines possess 2 intake (20) and two exhaust valves (19) per cylinder.Lubricating oil pressurized through the rocker arm bracket to the rocker arm shaft, which serves as a fulcrum so that the rocker arm and the entire system are lubricated sufficiently.Piston
Illustration 11 g03394192
(23) Concave Head Piston The reciprocating motion of a piston in the engine cylinder creates the forces for the suction, compression, power, and exhaust cycles.To be strong yet light, pistons are constructed of cast iron or aluminum alloys. Reinforcing ribs are used to keep the piston as light as possible.The piston head shape depends on the combustion chamber of the engine. A relatively deep concave head (23) is used for direct injection engines.The ring grooves are cut around the piston to fit the piston rings. The grooves are shaped to the proper rings for good control of oil and blow-by. The lower groove in which the oil ring is inserted has many holes for oil collected by oil ring to flow back to the crankcase.The piston lands are the areas between the ring grooves which hold and support the piston rings in the grooves. A fine groove called a heat dam is provided on the top land to protect the top ring from high temperatures.The skirt of the piston is the outside part below the ring grooves. The piston is kept in alignment by the skirt.The piston is kept in alignment by the skirt. The piston skirt has a