Hummer H3. Manual — part 449

Fig. 617: View Of Balance Shafts
Courtesy of GENERAL MOTORS CORP.

1. Lubricate the balance shaft bearing journals with clean engine oil.

2. Install NEW balance shaft assemblies with the counterweight down to prevent damage to

the balance shaft bearings.

3. Install NEW left balance shaft assembly retaining bolts.

Tighten: Tighten the NEW left balance shaft assembly retaining bolts to 10 N.m (89 lb in).

IMPORTANT: Do not disassemble the balance shaft assemblies. Remove

and install the balance shafts as complete assemblies.

NOTE:

Refer to FASTENER NOTICE .

2007 Hummer H3

2007 ENGINE Engine Mechanical - 3.7L - H3

Fig. 618: View Of Balance Shaft Chain Guide
Courtesy of GENERAL MOTORS CORP.

4. Install the balance shaft chain guide.

5. Install the balance shaft chain guide bolts.

Tighten: Tighten the balance shaft chain guide bolts to 10 N.m (89 lb in).

2007 Hummer H3

2007 ENGINE Engine Mechanical - 3.7L - H3

Fig. 619: View Of Balance Shaft Drive Chain
Courtesy of GENERAL MOTORS CORP.

6. Install the balance shaft chain onto the balancer sprockets and crankshaft sprocket.

IMPORTANT: Rotate the right balance shaft retainer plate counter-

clockwise to allow chain installation over all 3 sprockets.

2007 Hummer H3

2007 ENGINE Engine Mechanical - 3.7L - H3

Fig. 620: Sprocket Timing Marks
Courtesy of GENERAL MOTORS CORP.

7. Rotate the crankshaft until the left hand balance shaft sprocket timing mark is at 12:00. The

right hand balance shaft sprocket timing mark should be at 2:30. The crankshaft sprocket
mark should be at 4:30. Make sure the 3 timing marks on the sprockets (1) line up with a
dark link on the chain. Every 11 crankshaft rotations, 3 of the 5 dark links on the chain will
line up with the timing marks.

8. Rotate the retainer plate clockwise while holding the chain onto the crankshaft sprocket.

2007 Hummer H3

2007 ENGINE Engine Mechanical - 3.7L - H3