Camshaft: Service and Repair

Camshaft Replacement

Tools Required
^ J44643 Flywheel Holding Tool
^ J26900-13 Magnetic Base
^ J26900-12 Dial Indicator

Removal Procedure





1. Remove the valve lifters.
2. Remove the charged air cooler.
3. Remove the air conditioning (A/C) condenser.
4. Remove the radiator.
5. Remove the starter.
6. Install J44643 flush to the flywheel opening.
7. Remove the engine front cover.





8. Remove the oil pump driven gear nut.
9. Remove the oil pump driven gear.





Important: 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.

10. Remove the oil pump drive gear and crankshaft reluctor.
^ Do not remove the crankshaft reluctor bolts.
^ Do not damage the reluctor teeth.





11. Using J26900-12 (1) and J26900-13 (2), measure the camshaft end play.
^ The production value is 0.050 - 0.114 mm (0.002 - 0.0045 inch) and service limit is 0.20 mm (0.008 inch).
^ Replace the camshaft gear or the camshaft thrust plate if measured value exceeds service limit.





12. Remove the camshaft reluctor screws.
13. Remove the camshaft reluctor.





14. In order to loosen the camshaft gear bolt use J44643 in order to hold the engine from turning.
15. Loosen the camshaft gear bolt and leave the bolt finger tight.
16. Remove the camshaft thrust plate bolts through the holes in the camshaft gear.





17. Remove the camshaft with the camshaft gear attached.





18. Remove the camshaft gear bolt and discard.
19. Remove the camshaft gear.
20. Remove the camshaft thrust plate.
21. 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.

Installation Procedure





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.





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

Notice: Refer to Fastener Notice in Service Precautions.

6. Install the camshaft thrust plate bolts.
Tighten the bolts to 22 Nm (16 ft. lbs.).





7. Install the camshaft reluctor to the camshaft gear.
8. Install the camshaft reluctor bolts.
Tighten the bolts in a cross-bolt pattern to 9 Nm (80 inch lbs.).





9. Reinstall J44643 in the starter opening, if removed.
10. Install a NEW camshaft gear bolt.
Tighten the bolt to 234 Nm (173 ft. lbs.).





11. Using J26900-12 (1) and J26900-13 (2) measure the camshaft end play.
^ The production value is 0.050 - 0.114 mm (0.002 - 0.0045 inch) and service limit is 0.20 mm (0.008 inch).
^ Replace the camshaft gear or the camshaft thrust plate if measured value exceeds the service limit.





Important: 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 the nut to 100 Nm (74 ft. lbs.).
15. Install the engine front cover.
16. Install the starter.
17. Install the A/C condenser.
18. Install the radiator.
19. Install the charged air cooler.
20. Install the valve lifters.