Cylinder Head Disassemble (LGX)

Special Tools

• EN-8062  Valve Spring Compressor - Head Off
• EN-46116  Valve Stem Seal Remover/Installer
• EN-46117  Valve Stem Key Remover/Installer
• EN-46119  Off-Vehicle Valve Spring Compressor Adapter
• EN-49248  Injector Rail Assembly Remover

For equivalent regional tools, refer to Special Tools (LGX) .

Fig 1: Fuel Rail Bolts
Courtesy of GENERAL MOTORS COMPANY
1. Remove the fuel rail bolts (1) from the fuel rail (2).
Fig 2: Fuel Rail Injector Assembly And Remover
Courtesy of GENERAL MOTORS COMPANY
CAUTION:
• Remove the fuel rail assembly carefully in order to prevent damage to the injector electrical connector terminals and the injector spray tips. Support the fuel rail after the fuel rail is removed in order to avoid damaging the fuel rail components.
• Cap the fittings and plug the holes when servicing the fuel system in order to prevent dirt and other contaminants from entering open pipes and passages.
2. Remove the fuel rail and injectors (1) as an assembly using the EN-49248  remover.
Fig 3: Loosening Valve Keepers
Courtesy of GENERAL MOTORS COMPANY
NOTE:

Ensure valve heads will not contact anything during the following step in order to avoid bending or damage.

3. Using an appropriately sized deep socket and a plastic hammer, lightly tap on the valve spring retainer to loosen the valve keepers.
Fig 4: Compressing Valve Spring
Courtesy of GENERAL MOTORS COMPANY
WARNING:

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 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.

CAUTION:

Do not compress the valve springs to less than 24.0 mm (0.943 in). Contact between the valve spring retainer and the valve stem oil seal can cause potential valve stem oil seal damage.

4. Compress the valve spring using the EN-8062  compressor and the EN-46119  adapter.
Fig 5: Removing/Installing Valve Keepers
Courtesy of GENERAL MOTORS COMPANY
5. Use the magnet of the EN-46117  remover/installer in order to remove the valve keepers.
6. Remove the valve spring compressor and the adapter.
Fig 6: Valve Spring And Retainer
Courtesy of GENERAL MOTORS COMPANY
7. Remove the valve spring retainer.
8. Remove the valve spring.
Fig 7: Valve
Courtesy of GENERAL MOTORS COMPANY
9. Remove the valve.
Fig 8: Removing/Installing Valve Stem Oil Seals
Courtesy of GENERAL MOTORS COMPANY
NOTE:

NEVER reuse a valve stem oil seal.

10. Remove the valve stem oil seal using the EN-46116  remover/installer and discard.
11. Repeat these procedures for the remaining valves.
Fig 9: Cylinder Head Oil Gallery Expansion Plugs
Courtesy of GENERAL MOTORS COMPANY
12. Remove the cylinder head oil gallery expansion plugs.