PUMP GP-FUEL TRANSFER 1N4478 - Caterpillar

All 3512, D379, D398 And D399 EnginesThe new 6V3147 Main Bearing Wrench is used to loosen and tighten the nuts and bolts that fasten the main bearing caps to the block on all 3512, D379, D398 and D399 Engines. The wrench is used through the openings in the side of the block. See Illustration 1.
The 6V3147 Main Bearing Wrench has an 8H8534 Socket (1.125") on one end and an 8H8538 Socket (1 11/16") on the other end. The smaller, 8H8534 Socket fits the main bearing bolts on the 3512 Engines. The larger 8H8538 Socket fits the main bearing nuts on the D379, D398 and D399 Engines.
The 6V3147 Main Bearing wrench is used with a torque wrench. When installed at a right angle (90°) to the torque wrench, the indication on the torque wrench is the true torque the 6V3147 Main Bearing Wrench puts on the bolt or nut. If the 6V3147 Wrench is not used at a right angle (90°) to the torque wrench, the torque put on the bolt or nut will not be the same as the torque wrench indication. See Illustration 2.
Illustration 1.
Illustration 2. The 6V3147 Main Bearing Wrench correctly installed on a torque wrench.