Installation

INSTALL OR CONNECT

CAUTION: Failure to follow this procedure could result in severe engine damage.

1. Intake camshaft sprocket retaining bolt and washer, tighten to 70 Nm (52 lbs. ft.) holding sprocket with tool J 36013 or equivalent if removed. Use Adhesive / Sealant compound GM P / N 12345493 or equivalent on camshaft sprocket bolt.

2. Tool J 36008 or equivalent through holes in camshaft sprockets into holes in timing chain housing (this positions the camshafts for correct timing).

If the camshafts are out of position and must be rotated more than 1/8 turn in order to install the alignment dowel pins:
- The crankshaft must be rotated 90° clockwise off of TDC in order to give the valves adequate clearance to open.
- Once the camshafts are in position and the dowels installed, rotate the crankshaft counter clockwise back to top dead center.

CAUTION: Do not rotate the crankshaft clockwise to TDC, valve or piston damage could occur.

3. Timing chain over exhaust camshaft sprocket around idler sprocket and around crankshaft sprocket.

4. Remove the alignment dowel pin from the intake camshaft. Using tool J 36013 or equivalent rotate the intake camshaft sprocket counter clockwise enough to slide the timing chain over the intake cam sprocket.

Release the camshaft sprocket wrench J 36013 or equivalent. The length of chain between the two camshaft sprockets will tighten.

If properly timed the intake cam alignment dowel pin should slide in easily. If the dowel pin does not fully index the camshafts are not timed correctly, the procedure must be repeated.

5. Leave the alignment dowel pins installed.
6. Raise vehicle.
7. With slack removed from chain between intake cam sprocket and crankshaft sprocket the timing marks on the crankshaft and the cylinder block should be aligned. If marks are not aligned move the chain one tooth forward or rearward, remove slack and recheck marks.

Timing Chain Housing Fasteners:

8. Chain housing to block stud (timing chain tensioner shoe pivot). Tighten to 26 Nm (19 lbs. ft.).

Timing Chain Hydraulic Tensioner:

9. Reload timing chain tensioner assembly to its "zero" position as follows:
- Assemble restraint cylinder (56F), spring (56E), and nylon plug (56D) into plunger (56A). Index slot in restraint cylinder (56F) with peg (56C) in plunger.

While rotating the restraint cylinder clockwise, push the restraint cylinder into the plunger until it bottoms. Keep rotating the restraint cylinder clockwise but allow the spring to push it out of the plunger. The pin in the plunger will lock the restraint in the loaded position.
- Tool J 36589 or equivalent (56E) onto plunger assembly (56A)
- Plunger assembly (56A) into tensioner body (56H) with the long end (56B) toward the crankshaft when installed
10. Tensioner assembly (56) to chain housing
- Recheck plunger assembly installation, it is correctly installed when the long end (56B) is toward the crankshaft.

Disassembled Lower Engine:

Legend:

11. Timing chain tensioner bolts (72) and tighten to 10 Nm (89 lbs. in.).
12. Tensioner shoe (53) and tensioner shoe retainer (54)
13. Remove J 36589 or equivalent and squeeze plunger assembly into tensioner body to unload the plunger assembly.
14. Lower vehicle enough to reach and remove the alignment dowel pins.
15. Rotate crankshaft clockwise (normal rotation) two full rotations. Align crankshaft timing mark with mark on cylinder block and reinstall alignment dowel pins. Alignment dowel pins will slide in easily if engine is timed correctly.

CAUTION: If the engine is not correctly timed, severe engine damage could occur.

16. Three timing chain guides (Items 69, 70, 71).

Timing Chain And Housing:

17. Crankshaft oil slinger.
18. Engine front cover and torque to 12 Nm (106 lbs. in.).
19. Start engine inspect for oil leaks.