Chevrolet Silverado / GMC Sierra. Manual — part 263

Fig. 100: View Of Spark Plug Wire & Boot
Courtesy of GENERAL MOTORS CORP.

1. Remove the valve rocker arm. Refer to Valve Rocker Arm and Push Rod Replacement.

2. Disconnect the spark plug wire at the spark plug.

Twist each plug wire boot 1/2 turn.

Pull only on the boot in order to remove the wire from the spark plug.

2008 Hummer H2

2008 ENGINE Engine Mechanical - 6.2L - H2

Fig. 101: View Of Spark Plug And Sparkplug Seat
Courtesy of GENERAL MOTORS CORP.

3. Loosen the spark plug 1 or 2 turns.

4. Brush or air blast away any dirt or debris from around the spark plug.

5. Remove the spark plug.

IMPORTANT: Remove the spark plugs from the cylinder head with the

engine at room temperature.

2008 Hummer H2

2008 ENGINE Engine Mechanical - 6.2L - H2

Fig. 102: Applying Compressed Air To J 22794
Courtesy of GENERAL MOTORS CORP.

6. Install J 22794 into the spark plug hole. See Special Tools.

7. Attach an air hose to J 22794 . See Special Tools.

8. Apply compressed air to J 22794 in order to hold the valves in place. See Special Tools.

2008 Hummer H2

2008 ENGINE Engine Mechanical - 6.2L - H2

Fig. 103: Compressing Valve Spring (Cylinder Head Installed) Using Special Tools
Courtesy of GENERAL MOTORS CORP.

9. Use J 38606 in order to compress the valve spring. See Special Tools.

2008 Hummer H2

2008 ENGINE Engine Mechanical - 6.2L - H2