Primary Camshaft Drive Chain Installation

Tools Required 

J 39946  Crankshaft Socket - 4. See Special Tools .0L and 4.6L

Fig 1: Aligning Timing Marks Of Camshaft Intermediate & Crankshaft Sprockets
Courtesy of GENERAL MOTORS CORP.
1. Install the primary camshaft drive chain on the camshaft intermediate drive shaft sprocket and crankshaft sprocket.
2. Align the timing marks (1) of the camshaft intermediate drive shaft sprocket and crankshaft sprocket. Ensure the marks are aligned vertically.
Fig 2: Identifying Crankshaft Sprocket
Courtesy of GENERAL MOTORS CORP.
3. Ensure the number one piston is at Top Dead Center (TDC) and the crankshaft pin (1) is approximately at the one o'clock position using the J 39946  . See Special Tools .
4. Install the primary camshaft drive chain, camshaft intermediate drive shaft sprocket and crankshaft sprocket as an assembly (3) onto the camshaft intermediate drive shaft (4) and the crankshaft (2).
Fig 3: Identifying Camshaft Intermediate Drive Shaft Sprocket Bolt
Courtesy of GENERAL MOTORS CORP.
NOTE: Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.
5. Install the camshaft intermediate drive shaft sprocket bolt.

   Tighten:  Tighten the camshaft intermediate drive shaft sprocket bolt to 60 N.m (44 lb ft).

Fig 4: Locating Primary Camshaft Drive Chain Guide & Bolts
Courtesy of GENERAL MOTORS CORP.
6. Install the primary camshaft drive chain guide (1).
7. Install the primary camshaft drive chain guide bolts.

   Tighten:  Tighten the primary camshaft drive chain guide bolts to 25 N.m (18 lb ft).

Fig 5: Collapsing Primary Camshaft Drive Chain Tensioner
Courtesy of GENERAL MOTORS CORP.
8. Collapse the primary camshaft drive chain tensioner using the following procedure:
   1. Rotate the ratchet release lever counterclockwise and hold.
   2. Collapse the primary camshaft drive chain tensioner shoe and hold.
   3. Release the ratchet lever and slowly release the pressure on the shoe.
9. When the ratchet lever moves to the first detent a click should be heard and felt. Insert a pin through the hole in the release lever in order to lock the primary camshaft drive chain tensioner shoe in the collapsed position.
Fig 6: Identifying Primary Camshaft Drive Chain Tensioner to Engine Block Bolts
Courtesy of GENERAL MOTORS CORP.
IMPORTANT: Ensure the primary camshaft drive chain tensioner release lever is facing out.
10. Install the primary camshaft drive chain tensioner.
11. Install the primary camshaft drive chain tensioner bolts.

    Tighten:  Tighten the primary camshaft drive chain tensioner bolts to 25 N.m (18 lb ft).

12. Remove the pin in the release lever locking the primary camshaft drive chain tensioner.
Fig 7: Ensuring Vertical Timing Mark Alignment
Courtesy of GENERAL MOTORS CORP.
13. Ensure the timing marks (1) are aligned vertically.