ROLLER 9J0106 - Caterpillar

3508 (1ZF),
3512 (3YF),
3516 (4XF) High Horsepower Generator Set EnginesDescription of Change: A new cylinder head gasket is used on the high horsepower generator set engines. The new head gasket is designed to withstand the higher cylinder pressures experienced at the cylinder head joint.Adaptable To: The new 4P0601 Head Gasket replaces the 7W7730 Head Gasket in the 7C8120 Cylinder Head Group. However, the 7W7730 Head Gasket continues to be used in all of the other models of the 3500 Family Of Engines. The new gasket requires a cylinder head with a shot peened head (used since first production on high horsepower generator set engines) and a higher cylinder head bolt torque. See the NOTE below. The new head gasket is NOT interchangeable with the 7W7730 Head Gasket UNLESS a cylinder head with a shot peened top surface and a higher bolt torque are used.
If the 4P0601 Head Gasket is used without a shot peened head and a higher bolt torque, leakage of oil, water, or combustion gases at the cylinder head, or a cracked cylinder head could result. If the 7W7730 Head Gasket is used with the higher bolt torque, the cylinder block under the cylinder liner flange could crack.
This change is effective with 3508 (1ZF561), 3512 (3YF526), and 3516 (4XF344) Generator Set Engines.
The 4P0601 Head Gasket can be identified not only by the part number stamped on the gasket, but also by the letters "HT" (indicating High Torque) stamped on the upper right corner of the gasket.
Use the same numbering sequence for tightening the cylinder head bolts as shown in the appropriate Service Manual. Tighten bolts 1 through 8 in order, to a torque of 30 5 N m (22 4 lb ft). Then tighten the bolts in order again to a torque of 400 35 N m (296 26 lb ft). Finally, tighten the bolts once again in order, to a torque of 575 20 N m (425 15 lb ft).