Hummer H3. Manual — part 344

Housing Replacement.

2. Rotate the crankshaft until the left hand balance shaft sprocket timing mark (1) is at the 12

o'clock position. The right hand balance shaft sprocket timing mark (2) should be at the 2:30
position. The crankshaft sprocket timing mark (3) should be at the 4:30 position. Make sure
the 3 timing marks on the sprockets line up with a dark link on the chain.

Fig. 227: View Of Balance Shaft Chain Tensioner
Courtesy of GENERAL MOTORS CORP.

IMPORTANT: Every 11 crankshaft rotations, 3 of the 5 dark links on the

timing chain will line up with the timing marks.

2007 Hummer H3

2007 ENGINE Engine Mechanical - 3.7L - H3

3. Remove the balance shaft chain tensioner bolts.

4. Remove the balance shaft chain tensioner.

Installation Procedure

Fig. 228: View Of Balance Shaft Chain Tensioner
Courtesy of GENERAL MOTORS CORP.

IMPORTANT: It may be necessary to retract the tensioner plunger by

rotating the link plate clockwise. Insert a small tool into the
link plate hole in order the prevent the tensioner from
ratcheting to full extension.

2007 Hummer H3

2007 ENGINE Engine Mechanical - 3.7L - H3

1. Install a NEW balance shaft chain tensioner and bolts.

Tighten: Tighten the bolts to 10 N.m (89 lb in).

Fig. 229: View Of Sprocket Timing Marks
Courtesy of GENERAL MOTORS CORP.

2. Verify the correct timing chain timing mark alignments. The left hand balance shaft sprocket

timing mark (1) is at the 12 o'clock position. The right hand balance shaft sprocket timing
mark (2) should be at the 2:30 position. The crankshaft sprocket timing mark (3) should be
at the 4:30 position. The 3 timing marks on the sprockets line up with a dark link on the
chain.

NOTE:

Refer to Fastener Notice .

2007 Hummer H3

2007 ENGINE Engine Mechanical - 3.7L - H3

3. Install the crankshaft rear oil seal housing. Refer to Crankshaft Rear Oil Seal and

Housing Replacement.

BALANCE SHAFT DRIVE CHAIN REPLACEMENT

Removal Procedure

1. Remove the balance shaft chain tensioner. Refer to Balance Shaft Chain Tensioner

Replacement.

Fig. 230: View Of Balance Shaft Drive Chain
Courtesy of GENERAL MOTORS CORP.

2. Remove the balance shaft drive chain from the following:

2007 Hummer H3

2007 ENGINE Engine Mechanical - 3.7L - H3