Hummer H3. Manual — part 314

Fig. 123: Verifying Camshaft Placement With Straightedge
Courtesy of GENERAL MOTORS CORP.

24. To verify timing, set a straight edge across the flats of the camshafts.

2007 Hummer H3

2007 ENGINE Engine Mechanical - 3.7L - H3

Fig. 124: Measuring Clearance Under Camshaft Flats
Courtesy of GENERAL MOTORS CORP.

25. A 0.005 inch feeler gage should not be able to slip under the straight edge (1). If the feeler

gage slips under one or both camshaft flats, then the timing is off. Repeat step 20 and
recheck. If the camshaft flats are still not flat, the camshaft timing will have to be reset. This
may require removal and reinstallation of one or both camshaft sprockets.

26. Install the 1 long and 2 short cylinder head bolts next to the exhaust and intake timing chain

tensioner shoes and tighten the bolts.

27. Position the upper timing chain guide to the cylinder head. Apply threadlocker GM P/N

89021297 (Canadian P/N 10953488) to the upper timing chain guide bolt threads.

28. Install the upper timing chain guide bolts.

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

2007 Hummer H3

2007 ENGINE Engine Mechanical - 3.7L - H3

29. Install the radiator inlet hose and clamp to the cylinder head. Refer to Radiator Inlet Hose

Replacement (LLR) .

30. Clean and inspect the camshaft cover. Refer to Camshaft Cover Cleaning and

Inspection.

Fig. 125: View Of Camshaft Cover (Valve Cover)
Courtesy of GENERAL MOTORS CORP.

31. Install a NEW camshaft cover seal and NEW ignition control module seals to the cam cover.

Position the camshaft cover to the cylinder head.

32. Install the camshaft cover bolts.

2007 Hummer H3

2007 ENGINE Engine Mechanical - 3.7L - H3

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

33. Check the gap on all of the spark plugs. The gap should be 1.08 mm (0.042 in). Tighten all

of the spark plugs.

Tighten: Tighten the spark plug to 18 N.m (13 lb ft).

34. Install the ignition coils into the camshaft cover.

Fig. 126: View Of Ignition Control Module
Courtesy of GENERAL MOTORS CORP.

35. Install the ignition coil bolts.

2007 Hummer H3

2007 ENGINE Engine Mechanical - 3.7L - H3