Probable Causes
- Failure of the connecting rod bearing
- Damaged timing gears
- Damaged crankshaft
- Faulty accessory equipment
- Damaged unit injector rocker arm, missing insert, or broken socket
Recommended Repairs
Failure of the Connecting Rod Bearing
Inspect the bearings for the connecting rods and the bearing surfaces (journals) on the crankshaft. Install new parts, as required.
Damaged Timing Gears
Inspect the timing gears. Install new parts, as required.
Damaged Crankshaft
Replace the crankshaft.
Faulty Accessory Equipment
Repair the faulty components or install new components.
Damaged Rocker Arm on the Unit Injector, Missing Insert, or Broken Socket
Check for broken components or damaged components. Refer to Troubleshooting, "Unit Injector", Tool Operating Manual, NEHS0738, "Using the Injector Seating Tool " and Tool Operating Manual, NEHS0610, "Using the 128-8822 Tool Group on 3114, 3116, and 3126 Engines with Mechanical Unit Injectors (MUI)". Also, refer to Video Tape, LEVN4032, "Troubleshooting Guide for the 3100 Family of Diesel Engines" and Video Tape, LEVN4732, "Injector Seating Procedure". Repair components or install new components.