| Subject: | Valvetrain Tick at All Times - Inspect Oil Gallery Plug |
| Models: | 2004-2006 Buick Rainier |
| 2004-2006 Chevrolet Colorado |
| 2002-2006 Chevrolet Trailblazer |
| 2002-2004 Oldsmobile Bravada |
| with any of the following engines: |
| 2.8L Engine (VIN 8 - RPO LK5) |
| 3.5L Engine (VIN 6 - RPO L52) |
| 4.2L Engine (VIN S - RPO LL8) |
The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.
Condition/Concern:
On rare occasions, the oil gallery plug located between the number 1 cam journals may come out of position causing insufficient oil to the lash adjusters. This will result in a tick noise at all times from multiple lash adjusters.
Recommendation/Instructions:
If a tick noise at all times is encountered from multiple lash adjusters, ensure that the oil gallery plug between the front of both camshafts (shown below) is still pressed in place before replacing any lash adjusters. If the plug is no longer pressed
in place, follow SI repair procedures and replace the cylinder head.
Notice: It will be necessary to transfer all of the valvetrain components from the original cylinder head to the replacement cylinder head since the replacement cylinder head will come as a bare casting.
Please follow this diagnostic or repair process thoroughly and complete each step. If the condition exhibited is resolved without completing every step, the remaining steps do not need to be performed.
