Special Tools

1. Remove the valve lifters. Refer to Valve Lifter Replacement.
2. Remove the cooling layer. Refer to Cooling Layer Removal.
3. Remove the starter. Refer to Starter Motor Replacement.
4. Install J 44643 flush to the flywheel opening.
5. Remove the engine front cover. Refer to Engine Front Cover Replacement.



6. Remove the oil pump driven gear nut.
7. Remove the oil pump driven gear.




Note: The crankshaft reluctor and the oil pump drive gear are timed together at the factory. Do not remove the crankshaft reluctor from the oil pump drive gear.

8. Remove the oil pump drive gear and crankshaft reluctor.

•	Do not remove the crankshaft reluctor bolts.

•	Do not damage the reluctor teeth.




9. Using J 26900-12  (1) and J 26900-13  (2), measure the camshaft end play.

•	The production value is 0.050-0.114 mm (0.002-0.0045 in) and service limit is 0.20 mm (0.008 in).

•	Replace the camshaft gear or the camshaft thrust plate if measured value exceeds service limit.




10. Remove the camshaft reluctor screws.
11. Remove the camshaft reluctor.



12. In order to loosen the camshaft gear bolt use J 44643 in order to hold the engine from turning.
13. Loosen the camshaft gear bolt and leave the bolt finger tight.
14. Remove the camshaft thrust plate bolts through the holes in the camshaft gear.



15. Remove the camshaft with the camshaft gear attached.



16. Remove the camshaft gear bolt and discard.
17. Remove the camshaft gear.
18. Remove the camshaft thrust plate.
19. Clean and inspect the camshaft and bearings. Refer to Camshaft and Bearings Cleaning and Inspection.

If the camshaft bearings are worn or damaged the engine will require removal in order to replace the camshaft bearings. Refer to Engine Replacement .

1. Install the camshaft thrust plate to the camshaft.
2. Install the camshaft driven gear.
3. Install a NEW camshaft driven gear bolt.

Leave the bolt finger tight.




4. Install the camshaft into the cylinder block, align the camshaft gear to the crankshaft gear as shown.

Caution: Refer to Fastener Caution in the Preface section.




5. Apply threadlock GM P/N 12345493 (Canadian P/N 10953488), or equivalent to the threads of the camshaft thrust plate bolts.
6. Install the camshaft thrust plate bolts.

Tighten
Tighten the bolts to 22 N·m (16 lb ft).




7. Install the camshaft reluctor to the camshaft gear.
8. Install the camshaft reluctor bolts.

Tighten
Tighten the bolts in a cross-bolt pattern to 9 N·m (80 lb in).




9. Reinstall J 44643 in the starter opening, if removed.
10. Install a NEW camshaft gear bolt.

Tighten
Tighten the bolt to 234 N·m (173 lb ft).




11. Using J 26900-12  (1) and J 26900-13  (2) measure the camshaft end play.

•	The production value is 0.050-0.114 mm (0.002-0.0045 in) and service limit is 0.20 mm (0.008 in).

•	Replace the camshaft gear or the camshaft thrust plate if measured value exceeds the service limit.





Note: Do not damage the teeth on the crankshaft reluctor.

12. Install the oil pump drive gear and reluctor to the crankshaft.



13. Install the oil pump driven gear.
14. Install the oil pump driven gear nut.

Tighten
Tighten the nut to 100 N·m (74 lb ft).

15. Install the engine front cover. Refer to Engine Front Cover Replacement.
16. Install the starter. Refer to Starter Motor Replacement.
17. Install the cooling layer. Refer to Cooling Layer Installation.
18. Install the valve lifters. Refer to Valve Lifter Replacement.