Timing Chain: Service and Repair

Timing Chain and Sprockets Replacement

Tools Required

J 8614-01 Pinion Flange Holder

Removal Procedure




1. Remove the accessory drive belt.
2. Remove the generator from the engine.

Caution: Refer to Battery Disconnect Caution.

3. Disconnect the negative battery cable.
4. Drain the cooling system.
5. Install the engine support fixture.
6. Remove the engine mount and engine mounting bracket.
7. Remove the cylinder head cover.




8. Set the number 1 piston to the top dead center (TDC) position.
9. Align the camshaft timing sprockets.
10. Disconnect the power steering oil pressure switch connector.
11. Raise and properly support the vehicle.
12. Remove the right engine splash shield.




13. Remove the 2 power steering pump through bolts and the nuts (1).
14. Remove the power steering pump from the mounting surface.
Move the pump to the side.




15. Remove the crankshaft pulley retaining bolt using J 8614-01.
16. Remove the crankshaft pulley.




17. Remove the following components:
^ The crankshaft position sensor bolt (5)
^ The sensor
18. Lower the vehicle.
19. Remove the following components from the mounting surface:
^ The drive belt tensioner bolt
^ The drive belt tensioner nut
^ The drive belt tensioner




20. Remove the timing chain tensioner bolts (1, 2).
21. Remove the timing chain tensioner.




22. Remove the following fasteners:
^ The timing chain cover bolts (1-14)
^ The timing chain cover nut (15)
23. Remove the timing chain cover.




24. Remove the crankshaft sensor reluctor (1).




25. Remove the following components:
^ The timing chain dampener bolt (1)
^ The timing chain dampener
^ The timing chain shoe bolts (2)
^ The timing chain shoe




26. Remove the following components:
^ The crankshaft sprocket
^ The timing chain
27. Remove the three bolts from the front camshaft bearing cap.
28. Remove the front camshaft bearing cap in order to access the oil passage to the camshaft position (CMP) actuator.




29. Ensure that the CMP actuator will not turn.
30. Apply air pressure of approximately 100 kPa (14 psi) to the advance passage of the camshaft.
31. Turn the CMP actuator to the advanced angle side by hand.
32. Rotate the actuator back and forth through the advanced positions to ensure 21 degrees of movement.
33. Remove the air pressure and turn the CMP actuator back to the minimum advanced angle position to lock it.
34. Replace the CMP actuator if the following conditions exist:
^ CMP actuator does not lock with air pressure removed.
^ CMP actuator does not unlock with air pressure applied.
^ CMP actuator does not rotate smoothly through the advanced positions.
^ CMP actuator does not rotate completely through the advance positions.
35. Install the front camshaft bearing cap.

Notice: Refer to Fastener Notice.

36. Install the front camshaft bearing cap bolts.

Tighten the camshaft bearing cap bolts to 23 N.m (17 lb ft).

Installation Procedure




1. Use a wrench in order to align the camshaft timing marks.
Be sure to place the wrench on the hexagonal portion of the camshafts.




2. Turn the camshafts in order to align the timing marks.




3. Temporarily install the crankshaft bolt.
4. Turn the crankshaft until the crankshaft keyway (1) faces upward.




5. Install the following components:
^ The timing chain (2)
Install the timing chain on the crankshaft timing sprocket with the yellow color link aligned with the mark on the crankshaft timing sprocket.
^ The crankshaft timing sprocket





Notice: Refer to Fastener Notice.

6. Install the timing chain shoe. Secure the timing chain shoe using 2 bolts (1, 2).

Tighten the timing chain shoe bolts to 10 N.m (89 lb in).




7. Install the timing chain (1) onto the exhaust camshaft sprocket (4) and the intake camshaft sprockets (5).
Ensure that the yellow timing chain links (2) are aligned with the timing marks (3), (6). The intake cam phaser mark (7) should be at the 9 o'clock position and the "Ex" timing mark (8) on the exhaust camshaft sprocket (4) should be at the 3 o'clock position. The colored links (2) will line up around the 12 o'clock position with the double dots (3) on the exhaust sprocket and the line (6) on the cam phaser body.




8. Install the timing chain dampener. Secure the timing chain dampener using 1 bolt (1).

Tighten the timing chain dampener bolt to 18 N.m (14 lb ft).




9. Install the crankshaft sensor reluctor (1) onto the crankshaft. Insure that the F on the reluctor is facing outward.
10. Unlock the intake camshaft actuator locking pin.
11. Apply a continuous bead of GM P/N 12346240 (Canadian P/N 10953493) or an equivalent to the timing chain cover mating surface.




12. Install the timing chain cover.
Use the following fasteners in order to secure the cover:
^ Sixteen bolts (1,3,4,5)
^ Two nuts (2)
- Tighten the timing chain cover bolts (25 mm (0.98 in) head) to 13 N.m (10 lb in).
- Tighten the timing chain cover bolts (35 mm (1.38 in) head) to 11 N.m (8 lb ft).
- Tighten the timing chain cover bolts (20 mm (0.79 in) head) to 9 N.m (80 lb in).
- Tighten the timing chain cover bolts (45 mm (1.77 in) head) to 19 N.m (14 lb ft).
- Tighten the timing chain cover nuts to 10 N.m (89 lb in).




13. Use the following steps in order to install the timing chain tensioner:
1. Fully depress the plunger (4).
2. Apply the hook (2) to the pin (3).
3. Install the timing chain tensioner.




14. Install the timing chain tensioner. Secure the timing chain tensioner using 2 bolts (1).

Tighten the timing chain tensioner bolts to 10 N.m (89 lb in).




15. Install the right side engine mounting bracket. Secure the bracket using 3 bolts.

Tighten the engine mounting bracket bolts to 54 N.m (40 lb ft).

16. Install the drive belt tensioner. Secure the tensioner using 1 bolt and one nut.
^ Tighten the bolt to 69 N.m (51 lb ft).
^ Tighten the nut to 29 N.m (21 lb ft).
17. Raise the vehicle. Support the vehicle.
18. Install the crankshaft position sensor. Secure the sensor using 1 bolt (5).

Tighten the crankshaft position sensor bolt to 12 N.m (106 lb in).




19. Install the crankshaft pulley. Secure the crankshaft pulley using 1 bolt.

Tighten the crankshaft pulley to 142 N.m (105 lb ft).




20. Install the power steering pump.
21. Use the following fasteners in order to secure the power steering pump:
^ Two bolts (1)
^ Two nuts

Tighten the power steering pump bolts to 37 N.m (27 lb ft).

22. Install the right engine splash shield.
23. Lower the vehicle.
24. Connect the power steering oil pressure switch connector.




25. Rotate the crankshaft clockwise 1 revolution. Ensure that the plunger on the timing chain tensioner has released.
Complete the following steps if the plunger does not release:
^ Use a screwdriver or your finger in order to press the timing chain dampener into the timing chain tensioner.
^ Release the hook from the pin.
^ Verify proper timing chain alignment after the plunger has released.
26. Install the cylinder head cover.
27. Install the engine mount.
28. Remove the engine support fixture.
29. Install the generator.
30. Fill the cooling system.
31. Connect the negative battery cable.

Tighten the battery cable bolt to 15 N.m (11 lb ft).