PIN 7Y3550 - Caterpillar

Illustration 1 g00907738The mating surfaces of the connecting rod are produced by hydraulically fracturing the forged connecting rod. (1) Tighten the torx screws for the connecting rod to the following torque. ... 18 N m (13 lb ft)Tighten the torx screws for the connecting rod again to the following torque. ... 70 N m (52 lb ft)Tighten the torx screws for the connecting rod for an extra 120 degrees. The torx screws for the connecting rod (1) must be replaced after this procedure.Note: Always tighten the connecting rod cap to the connecting rod, when the assembly is out of the engine. Tighten the assembly to the following torque 20 N m (14 lb ft). (2) The bearing shell for the connecting rod
Illustration 2 g00995584
Alignment of the bearing shell
Note: The bearing shell for the connecting rod must be aligned equally from both ends of the connecting rod. Refer to (A) in figure 2. Refer to the Disassembly and assembly manual for information on the alignment tool.
Table 1
Bearing Width for the Connecting Rod 31.62 mm to 31.88 mm (1.245 inch to 1.255 inch)
Bearing Width for the Connecting Rod Cap 31.55 mm to 31.88 mm (1.241 inch to 1.255 inch)
Thickness of Connecting Rod Bearing at the Center 1.835 mm to 1.842 mm (0.072 inch to 0.073 inch)
Thickness of Connecting Rod Bearing for the Cap at the Center 1.835 mm to 1.842 mm (0.072 inch to 0.073 inch)
Bearing Clearance 0.030 mm to 0.081 mm (0.001 inch to 0.003 inch)
Table 2
Undersized Connecting Rod Bearing
0.25 mm (0.010 inch)
0.51 mm (0.020 inch)
0.76 mm (0.030 inch)
Illustration 3 g00907744 (3) Diameter of the parent bore for the piston pin ... 43.01 mm to 43.04 mm (1.693 inch to 1.694 inch) (4) Distance between the parent bores ... 219.05 mm to 219.10 mm (8.624 inch to 8.626 inch) (5) Diameter for the parent bore for the connecting rod bearing ... 67.21 mm to 67.22 mm (2.646 inch to 2.647 inch)
Illustration 4 g00915056Connecting rods are color coded. The color code is a reference for the length (Y) of the connecting rod. Refer to table 3 for the different lengths of connecting rods.
Table 3
Length Grades for Connecting Rods
Grade Letter Color Code Length (Y)
F Red 165.728 mm to 165.761 mm (6.525 inch to 6.526 inch)
G Orange 165.682 mm to 165.715 mm (6.523 inch to 6.524 inch)
H White 165.637 mm to 165.670 mm (6.521 inch to 6.522 inch)
J Green 165.591 mm to 165.624 mm (6.519 inch to 6.521 inch)
K Purple 165.545 mm to 165.578 mm (6.518 inch to 6.519 inch)
L Blue 165.499 mm to 165.532 mm (6.516 inch to 6.517 inch)