WIRING GP-PLATFORM 3440215 - Caterpillar

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).