Balancer Chain, Sprocket, And Tensioner Installation

Special Tools 

EN-50837  Timing Chain Tensioner Retraction Tool

For equivalent regional tools, refer to Special Tools .

Fig 1: Timing Link Lines & Timing Mark
Courtesy of GENERAL MOTORS COMPANY
NOTE:

Proper setup is critical to ensure correct timing when installing the sprockets and chain simultaneously onto the shafts. The timing links are heat treated blued steel.

1. Assemble the crankshaft sprocket, balancer shaft driven sprocket, and balancer chain. Ensure the timing link (1) lines up with the timing mark (2) on the crankshaft sprocket. Ensure that both timing teeth (3) on the balancer shaft driven sprocket line up with the timing links (4).
Fig 2: Balancer Shaft Driven Sprocket And Balancer Chain
Courtesy of GENERAL MOTORS COMPANY
NOTE:

The crankshaft keyway should be in the 12 O'clock position.

2. Install the sprockets and chain (2) as an assembly to the crankshaft and balancer shaft assembly.
3. Install the crankshaft key (1).
Fig 3: Timing Link Lines & Timing Mark
Courtesy of GENERAL MOTORS COMPANY
4. Ensure the timing link (1) is aligned with the crankshaft sprocket timing mark (2).
5. Ensure the adjacent timing links (4) are aligned with both of the timing marks (3) on the balancer shaft driven sprocket.
Fig 4: Balancer Shaft Driven Sprocket Bolt
Courtesy of GENERAL MOTORS COMPANY
CAUTION:

This vehicle is equipped with torque-to-yield or single use fasteners. Install a NEW torque-to-yield or single use fastener when installing this component. Failure to replace the torque-to-yield or single use fastener could cause damage to the vehicle or component.

6. Install the NEW balancer shaft driven sprocket bolt (1).
CAUTION:

Refer to Fastener Caution .

7. Use an open end wrench over flat on balance shaft while tightening the balancer shaft sprocket bolt to specification. tighten the balancer shaft driven sprocket bolt to 40 N.m (30 lb ft) plus 50 degrees.
Fig 5: Balancer Chain Guide Bolt
Courtesy of GENERAL MOTORS COMPANY
NOTE:

Ensure the guide is installed in the correct orientation. The long end must point toward the crankshaft and the flat edge must be adjacent to the balance chain.

8. Install the balancer chain guide (2).
9. Install the balancer chain guide bolts (1). tighten the bolts to 10 N.m (89 lb in).
Fig 6: Balancer Chain Tensioner Bolt
Courtesy of GENERAL MOTORS COMPANY
10. Install the balancer chain tensioner (2).
11. Install the balancer chain tensioner bolts (1). tighten the bolts to 10 N.m (89 lb in).
12. Remove EN-50837  retention tool to restore the tension to the balancer chain.