Hummer H3. Manual — part 523

Fig. 126: Compressing Valve Spring (Cylinder Head Installed) Using Special Tools
Courtesy of GENERAL MOTORS CORP.

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

2008 Hummer H3

2008 ENGINE Engine Mechanical - 5.3L - H3

Fig. 127: Valve Stem Keys, Valve Spring Cap & Valve Spring
Courtesy of GENERAL MOTORS CORP.

10. Remove the valve stem keys (225).

11. Carefully release the valve spring tension.

12. Remove the J 38606 . See Special Tools.

13. Remove the valve spring cap (224).

14. Remove the valve spring (223).

2008 Hummer H3

2008 ENGINE Engine Mechanical - 5.3L - H3

15. Remove the valve stem oil seal (222).

16. Remove the valve (228).

Installation Procedure

Fig. 128: Valve Stem Keys, Valve Spring Cap & Valve Spring
Courtesy of GENERAL MOTORS CORP.

1. Clean the cylinder head valve spring seat area.

2008 Hummer H3

2008 ENGINE Engine Mechanical - 5.3L - H3

2. Lubricate the valve guide and valve stem oil seal with clean engine oil.

3. Install the valves (228) into the proper port.

4. Install the valve stem oil seal (222).

5. Install the valve spring (223).

6. Install the valve spring cap (224).

Fig. 129: Compressing Valve Spring (Cylinder Head Installed) Using Special Tools
Courtesy of GENERAL MOTORS CORP.

7. Compress the valve spring using the J 38606 . See Special Tools.

8. Install the valve keys.

Use grease in order to hold the valve keys in place.

2008 Hummer H3

2008 ENGINE Engine Mechanical - 5.3L - H3