- Engine:
- 3176C (S/N: 2AW1-UP; 6BW1-UP)
- Industrial Engine:
- C-10 PETROLEUM (S/N: Z2B1-UP)
- Marine Engine:
- C12 (S/N: C1Z1-UP)
- 3196 (S/N: 2XR1-UP; 1DW1-UP)
- C-10 (S/N: BCX1-UP)
- C-12 (S/N: BDL1-UP; 9HP1-UP; BCY1-UP)
After a hard injector seizure, replace the injector and the camshaft injector lifter assembly for the corresponding cylinder. A hard injector seizure occurs when the injector plunger fails on the down stroke. As the plunger seizes, separation occurs in the mechanism and the fuel injector pushrod cup disengages from the insert for the rocker arm. This crushes the pushrod between the rocker arm and the lifter assembly. As a result, the roller follower pin becomes damaged. This damage is not visible.
Illustration 1 | g01278913 |
(A) 90 ± 10 degrees (1) Lifter body (2) Roller (3) Roller axle |
If the cylinder head is removed for either a repair of a lifter or for any other reason, the position of the arrows on the lifter roller axle on all six unit injector lifter assemblies needs to be examined. If the position arrow is more than 10 degrees from vertical, the camshaft injector lifter assembly should be replaced. The incorrect position of the arrow indicates that the roller axle has begun to turn in the lifter body and the oil that is gathering on top of the axle is not correctly positioned. The roller axle will not be lubricated properly. If the axle has turned into the lifter body the roller may eventually separate from the lifter body. This can cause damage to the cylinder block.
If the damage to the camshaft lobe is due to failures that are listed above, submit the Caterpillar warranty claim against the lifter.