NUT 4799266 - Caterpillar

Piston, Rings And Connecting Rods
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(1) Piston
(2) Piston cooling jet
(3) Connecting rod High output engines with high cylinder pressures require two-piece articulated pistons. The two-piece articulated piston consists of a forged steel crown that is connected to an aluminum skirt by the piston pin. Refer to the Parts Manual in order to obtain information about the type of pistons that are used in a specific engine.
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(4) Compression ring
(5) Intermediate ring
(6) Oil ring
(7) Forged steel crown
(8) Aluminum skirt All of the rings are located above the piston pin bore. The compression ring is a Keystone ring. Keystone rings have a tapered shape. The action of the ring in the piston groove that is tapered helps prevent seizure of the rings. Seizure of the rings is caused by deposits of carbon. The intermediate ring is rectangular with a sharp lower edge. The oil ring is a standard type of ring or a conventional type of ring. Oil returns to the crankcase through holes in the oil ring groove.Oil from the piston cooling jets sprays the underside of the pistons. The spray lubricates the pistons and the spray cools the pistons. The spray also improves the piston's life and the spray also improves the ring's life.The connecting rod has a taper on the pin bore end. Two bolts hold the connecting rod cap to the connecting rod. The connecting rod can be removed through the cylinder.Crankshaft
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(1) Crankshaft
(2) Gear The crankshaft converts the linear motion of the pistons into rotational motion. A