Intake Camshaft Installation

Special Tools

• EN-50509  Split Intake Camshaft Sprocket Fixing Tool
• EN-51143  Camshaft Sprocket Fixing Tool

For equivalent regional tools, refer to Special Tools .

NOTE:

Before installing the intake camshaft, check the components of the timing chain system for damage and wear.

1. Check the components of the timing chain system for damage and wear:
   • Timing chain guides with plastic attachment
   • Timing chain tensioner and timing chain tensioner shoe with plastic attachment
   • Timing chain and all timing chain sprockets
   • Oil pump sprocket
   • Oil pump drive chain tensioner
Fig 1: Marking Camshaft Sprockets With Paint Marks By Transmitting Front Marks
Courtesy of GENERAL MOTORS COMPANY
NOTE:

Transmit the front marks (1) on the back of the camshaft sprockets.

2. Marking the exhaust camshaft sprocket and intake camshaft sprocket with paint marks (2), by transmit the front marks (1).
Fig 2: Intake Camshaft With Camshaft Sprocket Marks Aligned
Courtesy of GENERAL MOTORS COMPANY
3. Coat all bearing surfaces with engine oil.
NOTE:

Ensure the marks (2) of the camshaft sprocket are aligned.

4. Install the intake camshaft (1).
Fig 3: Marking Exhaust Camshaft Sprocket And Intake Camshaft Sprocket With Paint Marks
Courtesy of GENERAL MOTORS COMPANY
5. Check the marks (1) of the camshaft sprockets whether they are aligned.
Fig 4: Intake Camshaft Bearing Caps And Bolts
Courtesy of GENERAL MOTORS COMPANY
NOTE:

Note the arrows as marks on the camshaft bearing caps, which shows on the outside of the cylinder head.

6. Install the intake camshaft bearing caps (2) in the order as they was removed.
7. Install the intake camshaft bearing cap bolts (1).
Fig 5: Intake Camshaft Bearing Cap Bolt Tightening Sequence
Courtesy of GENERAL MOTORS COMPANY
CAUTION:

Refer to Fastener Caution .

8. Tighten the 8 intake camshaft bearing cap bolts in sequence as shown to 10 N.m (89 lb in).
Fig 6: Split Intake Camshaft Sprocket Fixing Tool
Courtesy of GENERAL MOTORS COMPANY
9. Remove the EN-50509  fixing tool (1) or the transport lock from the exhaust camshaft sprocket (2).
Fig 7: Camshaft Bearing Rear Cap And Bolts
Courtesy of GENERAL MOTORS COMPANY
10. Coat all bearing surfaces with engine oil.
11. Install the camshaft bearing rear cap (2).
12. Install the 4 camshaft bearing rear cap bolts (1).
Fig 8: Camshaft Rear Cap Bolt Tightening Sequence
Courtesy of GENERAL MOTORS COMPANY
13. Tighten the 4 camshaft rear cap bolts in sequence as shown to 25 N.m (18 lb ft).
Fig 9: Camshaft Fixing Tool
Courtesy of GENERAL MOTORS COMPANY
14. Install the EN-51143  fixing tool (1), by carefully turning the hexagon of the camshaft.