Camshaft Replacement

Removal Procedure

- Tools Required
- J 38822 Cam Chain Holder





1. Remove the left side cam cover.
2. Remove the right side cam cover.
3. Secure the camshaft sprockets to the timing chain by installing tie-wraps through the cam sprocket holes. Use four tie-wraps per sprocket.

Important: The sprocket/chain relationship must be maintained throughout this procedure or the camshaft timing will be lost. This will require further engine disassembly to retime.

4. Working behind the sprockets, install cam chain holder J 38822.

Important: Note the relative location of the cam drive pins in the end of the camshafts.

5. Remove both cam sprocket bolts.
6. Work the sprockets off of the cams using the play in the chain.
7. Alternately loosen the cam bearing cap screws a few turns at a time until all valve spring pressure has been released.
8. Remove the bolts and the bearing caps.





9. Remove the camshaft,
- Whenever removing a camshaft from an engine with a suspected faulty camshaft operation, the camshaft lobes should be visually checked and measured.
- Excessive wear, scoring or flaking of the lifter will usually denote camshaft wear.
- Excessive camshaft lobe wear is evidenced by grooves, scoring or flaking.
- The bearing journals should not be scored or burned.
- The camshafts should be replaced if any of these conditions exist.

Installation Procedure





1. Apply the camshaft prelube, GM P/N 1052365, to the face of each cam lobe.

Important:
- Each cap is identified for position and direction.
- The arrow points toward the front of the engine.
- E indicates a cap for the exhaust cam.
- I indicates a cap for the intake cam.
- Position 1 is from the front of the engine.

2. Install the camshaft.
3. Position the cam bearing caps to the cylinder head.
4. Loosely install the cam bearing cap bolts.

Notice: Refer to Fastener Notice in Service Precautions.

5. Alternately tighten each bearing cap bolt a few turns at a time against the valve spring pressure until all the bolts are snug.
- Tighten the bearing cap bolts to 12 Nm (106 inch lbs.).





6. Using the hex cast into the camshaft, rotate the cams until the drive pins are in position to engage the cam sprockets over the cams.
7. Work the cam sprockets over the cams.
8. Install the remaining bolts.
- Tighten the sprocket bolts to 120 Nm (90 ft. lbs.).
9. Remove chain holder J 38822
10. Remove the tie-wraps from the cam sprockets.
11. Install the left side cam cover.
12. Install the right side cam cover.