Hummer H3. Manual — part 1158

Fig. 1: View Of Exhaust Manifold
Courtesy of GENERAL MOTORS CORP.

1. Remove the secondary air injection (AIR) check valve. Refer to Secondary Air Injection

Check Valve Replacement .

2. Remove the exhaust seal. Refer to Exhaust Seal Replacement.

3. Remove the exhaust manifold heat shield. Refer to Exhaust Manifold Heat Shield

CAUTION: Refer to Exhaust Service Caution .

CAUTION: Refer to Protective Goggles and Glove Caution .

2007 Hummer H3

2007 ENGINE Engine Exhaust - H3

Replacement.

4. Remove the exhaust manifold bolts.

5. Remove the exhaust manifold.

Fig. 2: View Of Exhaust Manifold Gasket
Courtesy of GENERAL MOTORS CORP.

6. Remove and discard the exhaust manifold gasket.

7. Clean and inspect the exhaust manifold. Refer to Exhaust Manifold Cleaning and

Inspection .

Installation Procedure

2007 Hummer H3

2007 ENGINE Engine Exhaust - H3

Fig. 3: View Of Exhaust Manifold Gasket
Courtesy of GENERAL MOTORS CORP.

1. Clean and apply threadlock GM P/N 12345493 (Canadian P/N 10953488) to the exhaust

manifold bolt threads.

2. Position a NEW exhaust manifold gasket onto the cylinder head.

2007 Hummer H3

2007 ENGINE Engine Exhaust - H3

Fig. 4: View Of Exhaust Manifold
Courtesy of GENERAL MOTORS CORP.

3. Position the exhaust manifold against cylinder head.

4. Install the exhaust manifold bolts.

2007 Hummer H3

2007 ENGINE Engine Exhaust - H3