Chevrolet Silverado / GMC Sierra. Manual - part 371
Fig. 484: Valve Stem Keys, Valve Spring Cap & Valve Spring
Courtesy of GENERAL MOTORS CORP.
1. Clean the cylinder head valve spring shim area.
2. Install the valves (228) into the proper port. Refer to Separating Parts.
IMPORTANT: When using the valves and related components again, install
the parts to their original location.
2008 Hummer H2
2008 ENGINE Engine Mechanical - 6.2L - H2
3. Install the valve stem oil seal (222).
4. Install the valve spring (223).
5. Install the valve spring cap (224).
Fig. 485: Compressing Valve Spring Using
Courtesy of GENERAL MOTORS CORP.
2008 Hummer H2
2008 ENGINE Engine Mechanical - 6.2L - H2
6. Using the J 8062 , compress the valve spring. See Special Tools.
7. Install the valve stem keys.
1. Use grease in order to hold the keys in place and remove the J 8062 . See Special
Tools.
2. Ensure the keys seat properly in the groove of the valve stem.
3. Tap the end of the valve stem with a plastic face hammer to seat the keys, if necessary.
Fig. 486: Measuring Valve Spring Installed Height
Courtesy of GENERAL MOTORS CORP.
8. Using a ruler, measure the valve spring installed height.
2008 Hummer H2
2008 ENGINE Engine Mechanical - 6.2L - H2
Measure from the base of the valve spring to the top of the valve spring.
Specification:
If the installed height exceeds 46.25 mm (1.82 in), install a valve spring shim of
approximately 0.5 mm (0.02 in) thick.
Do not shim the valve spring to obtain less than the specified height.
Do not assemble the components without a spring shim on the cylinder head.
9. Install the remaining valves, springs, and other components.
2008 Hummer H2
2008 ENGINE Engine Mechanical - 6.2L - H2