3500B Engines and 776D, 777D, 784C, 785C, 789C, 793C and 793D Off-Highway Truck/Tractors Caterpillar

Piston and Rings - Two-Piece Piston

Usage:

789C 2BW

Show/hide table




Illustration 1	g02612156
Typical example

Show/hide table

Table 1
Specification for 160-5910 Piston and Rod Gp
Item	Qty	Part	Specification Description
This piston has a Keystone top ring. This piston also has Keystone intermediate rings. The 204-8041 Piston Ring Groove Gauge Gp is necessary for measuring the ring grooves in the Keystone pistons. For correct use of the gauge group, refer to the instruction card that is with the gauge group.
Prior to the installation of the rings, lubricate the ring grooves with clean engine oil. Lubricate the mating surfaces of the rings to the cylinder liner with clean engine oil, after assembly.
1	1	229-1632 Top Piston Ring	Install the piston ring with the "Up-1" side toward the top of the piston.
			When the piston ring is installed in a cylinder liner with a bore size of 170 mm (6.7 inch), the clearance between the ends of the piston ring is 0.625 ± 0.125 mm (0.0246 ± 0.0049 inch).
			The increase in the clearance between the ends of the piston ring for each 0.03 mm (0.001 inch) increase in the cylinder liner bore size is 0.08 mm (0.003 inch).
			Thickness of the new top piston ring is 4.5 mm (0.18 inch).
2	1	144-5695 Intermediate Piston Ring	Install the piston ring with the "Up-2" side toward the top of the piston.
			When the piston ring is installed in a cylinder liner with a bore size of 170 mm (6.7 inch), the clearance between the ends of the piston ring is 1.00 ± 0.15 mm (0.039 ± 0.006 inch).
			The increase in the clearance between the ends of the piston ring for each 0.03 mm (0.001 inch) increase in the cylinder liner bore size is 0.08 mm (0.003 inch).
			Thickness of the new intermediate piston ring is 3.785 mm (0.1490 inch).
3	1	165-6668 Oil Control Piston Ring	Width of groove in piston for the new oil piston ring is 4.055 ± 0.015 mm (0.1596 ± 0.0006 inch).
			Thickness of new oil piston ring is 3.980 ± 0.010 mm (0.1567 ± 0.0004 inch).
			Clearance between groove and new oil piston ring is 0.050 mm to 0.100 mm (0.0020 mm to 0.0039 inch).
			When the piston ring is installed in a cylinder liner with a bore size of 170 mm (6.7 inch), the clearance between the ends of the piston ring is 0.65 ± 0.15 mm (0.026 ± 0.006 inch).
			The increase in the clearance between the ends of the piston ring for each 0.03 mm (0.001 inch) increase in the cylinder liner bore size is 0.08 mm (0.003 inch).
-	-	-	Install the oil piston ring so that the gap in the spring is 180 degrees away from the gap in the piston ring. The white portion of the spring must be visible at the ring end gap. After all of the piston rings have been installed, rotate the piston rings so that the end gaps are separated by 120 degrees. The ring gap for the oil piston ring must be aligned in the plane of the pin bore.
4	-	-	Before assembly of the piston pin, lubricate the piston pin, the piston pin bore, the connecting rod eye, and the connecting rod pin bearing with clean engine oil.
	1	172-0919 Crown As	Measure the pin bore in the bushings in two places for each bushing in a vertical direction. Bore for the piston pin is 70.0525 ± 0.0075 mm (2.75796 ± 0.00029 inch).
	1	155-5271 Piston Skirt	Measure the pin bore in a vertical direction. Bore is 69.988 ± 0.005 mm (2.7554 ± 0.0002 inch).
5	1	138-8508 Piston Pin	Measure the pin diameter on each end in a vertical and horizontal direction. Outside diameter is 69.962 ± 0.005 mm (2.7544 ± 0.0002 inch). Inside diameter is 33.0 ± 0.5 mm (1.30 ± 0.02 inch). Length is 137.55 ± 0.15 mm (5.415 ± 0.006 inch).
6	2	8N-7296 Pin Retainer	Assemble the pin retainer with the opening towards top of the piston.