Usage:
793 (3SJ),
793B (1HL),
793C (4GZ) Off-Highway Trucks
Description of Change: Blocks have been added to the turbocharger groups on the 3516 engines in these trucks. The blocks will prevent the rotation of the low pressure turbocharger bearing housing if the turbocharger shaft seize to the bearing housing. If the bearing housing rotates, the turbocharger oil supply and/or the oil drain lines can separate from the bearing housing. If the engine continues to run with one of these lines disconnected, oil will run out on top of the engine.
Illustration 1.
(TOP VIEW) Locations of the 6V-4249 Bolts (1), 3E-4249 Washers (2), and 156-6231 Blocks (3) on the low pressure turbochargers in a typical turbocharger group.
Adaptable To: Eight 6V-4249 Bolts (1), eight 3E-4249 Washers (2), and four 156-6231 Blocks (3) have been added to the 9Y-8911, 108-5559, 147-0790, and 147-0810 Turbocharger Groups used on the 3516 engines in these trucks. The new blocks and hardware are effective with 793C (4GZ1-Up, 4AR316-Up) Off-Highway Trucks. The new blocks and hardware are effective with 3516 machine engines as listed in the following chart. At overhaul, the blocks can be reused unless a seizure has occurred.
Illustration 2.
Orientation of 156-6231 Blocks (3) on the turbocharger bearing housing (B).
The rounded corner (A) of the block goes toward the oil line.
When installing the 156-6231 Blocks, the rounded corner of the block should be toward the oil line. See Illustration 2. Tighten the 6V-4249 Bolts (1) to a torque of 55 ± 10 N·m (40 ± 7 lb ft). Then tighten bolts (1) again to a torque of 55 ± 10 N·m (40 ± 7 lb ft).