Hummer H3. Manual — part 301

Fig. 74: View Of EN 46547
Courtesy of GENERAL MOTORS CORP.

3. Install the EN 46547 (1) into the flywheel teeth. See Special Tools.

4. Lower the vehicle.

5. Remove the camshafts. Refer to Camshaft Replacement.

6. Remove the spark plugs. Refer to Spark Plug Replacement .

2007 Hummer H3

2007 ENGINE Engine Mechanical - 3.7L - H3

Fig. 75: View Of J 44228 Base Plate
Courtesy of GENERAL MOTORS CORP.

7. Install the base plate of the J-44228-A over the spark plug hole of the cylinder to be

serviced.

8. Install the J 39313 in the spark plug hole. See Special Tools.

9. Apply constant air pressure to the J 39313 in order to keep the valve closed. See Special

Tools.

10. Install the arm and swivel nut of the J-44228-A over the stud corresponding to the valve to

be serviced.

CAUTION: Compressed valve springs have high tension against the

valve spring compressor. Valve springs that are not
properly compressed by or released from the valve spring
compressor can be ejected from the valve spring

2007 Hummer H3

2007 ENGINE Engine Mechanical - 3.7L - H3

11. Tighten the swivel nut of the J-44228-A down only enough to allow access for removal of

the valve locks.

Fig. 76: View Of Valve Locks
Courtesy of GENERAL MOTORS CORP.

12. Remove the valve locks. A magnet is the most suitable tool for this activity.

13. Loosen the swivel nut of the J-44228-A and swing the arm away from the valve spring

retainer.

compressor with intense force. Use care when
compressing or releasing the valve spring with the valve
spring compressor and when removing or installing the
valve stem keys. Failing to use care may cause personal
injury.

2007 Hummer H3

2007 ENGINE Engine Mechanical - 3.7L - H3

Fig. 77: View Of Valve Springs & Retainers
Courtesy of GENERAL MOTORS CORP.

14. Remove the valve spring retainer and valve spring.

2007 Hummer H3

2007 ENGINE Engine Mechanical - 3.7L - H3