New Cylinder Head Groups Are Now Used on Certain C175 Off-Highway Truck Engines {1100} Caterpillar

Off-Highway Truck/Tractor

793F (S/N: SND1-UP; SSP1-UP; SXP1-UP; RBT1-UP)

794 AC (S/N: MN51-UP; MT51-UP)

795F AC (S/N: ERM1-UP)

795FAC XQ (S/N: SNT1-UP)

797F (S/N: LAJ1-UP; WSP1-UP)

Description Of Change: The new cylinder head groups incorporate two changes.

• An improved torque process for the injector sleeve. Antiseize is applied to the threads of the injector sleeve and the injector sleeve is torqued to 200 N·m (148 lb ft), backed off 180 degrees, and retorqued to 200 N·m (148 lb ft).

• A change to the intake valve and valve stem seal. The new valve has an improved interference angle with the valve seat. The new seal improves lubrication to the valves. The new 513-3495 Valve and 519-6446 Seal replace the former 273-1224 Valve and 318-4779 Seal.

Adaptable To: The new and former cylinder head groups are listed in Table 2.

The 20R-1382 Cylinder Head Gp has this new torque process incorporated starting with the cylinder head date code 245161.

The torque process change is effective for the Reman engines that were built with the improved process head groups listed in Table 1.

The new cylinder head groups are adaptable to the above engines back to first production.

The new cylinder head groups with the torque process change, new valves, and stem seals are listed in Table 2.

These changes are effective for the engine serial numbers listed in Table 3.