PUMP GP-FUEL INJECTION 5117975 - Caterpillar

Cylinder Head
Illustration 2 g03876150
(1) Valve Keepers
(2) Valve Spring Retainer
(3) Valve Spring
(4) Stem Seal
(5) Cylinder Head
(6) ValveThe engine has a cast iron cylinder head (5). The inlet manifold is integral within the cylinder head. There are two inlet valves and two exhaust valves for each cylinder. Each pair of valves (6) are connected by a valve bridge that is controlled by a pushrod valve system. The ports for the inlet valves are on the left side of the cylinder head. The ports for the exhaust valves are on the right side of the cylinder head. The valve stems move in valve guides that are pressed into the cylinder head. There is a renewable stem seal (4) that fits over the top of the valve guide. The valve seats are replaceable.Pistons, Rings, and Connecting rods
Illustration 3 g02394336
Typical example
The pistons (9) have a quiescent combustion chamber in the top of the piston in order to provide an efficient mix of fuel and air. The piston pin (8) is off-center in order to reduce the noise level. The position pin (8) is retained in the correct position by two circlips (3).The pistons have two compression rings (1) and an oil control ring (2). The groove for the top ring has a hard metal insert in order to reduce wear of the groove. The piston skirt has a coating of graphite in order to reduce the risk of seizure when the engine is new to reduce friction and improve fuel economy.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.The connecting rods (4) are machined from forged steel. The connecting rods have bearing caps (6) that are fracture split. Two connecting rod bearings (5) are installed between the connecting rod (4) and the bearing cap (6). The bearing caps on fracture split connecting rods are retained with Torx bolts (7). Connecting rods with bearing caps that are fracture split have the following characteristics:
The splitting produces an accurately matched surface on each side of the fracture for improved strength.
The correct connecting rod must be installed with the correct bearing cap. Each connecting rod and bearing cap have a unique serial number. When a connecting rod is assembled, the serial numbers for the connecting rod and bearing cap must match.Crankshaft
Illustration 4 g03874723
Typical example
(1) Crankshaft gear
(2) Crankshaft
(3) Crankshaft timing ringThe crankshaft is a chromium molybdenum steel forging. The crankshaft has seven main journals. Thrust washers are installed on both sides of number six main bearing in order to control the end play of the crankshaft.The crankshaft changes the linear force of the pistons and connecting rods into rotary torque in order to power external equipment.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:
Camshaft gear
Fuel injection pump and fuel transfer pump
The idler gear