Primary Camshaft Drive Chain Installation - Off Vehicle

Tools Required 

J 39946  Crankshaft Socket - 4.0L and 4.6L. See Special Tools .

Fig 1: Friction Washers
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IMPORTANT: Ensure the proper friction washer is installed in the correct position.
1. Select the crankshaft to crankshaft sprocket friction washer (1). The outer diameter is 63.5 mm (2.5000 in), an inner diameter of 45.25 mm (1.7815 in) and a notch to clear the crankshaft pin.
Fig 2: Crankshaft To Crankshaft Sprocket Friction Washer
Courtesy of GENERAL MOTORS CORP.
2. Install the crankshaft to crankshaft sprocket friction washer.
Fig 3: Aligning Timing Marks Of Camshaft Intermediate & Crankshaft Sprockets
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3. Install the primary camshaft drive chain on the camshaft intermediate drive shaft sprocket and crankshaft sprocket.
4. Align the timing marks (1) of the camshaft intermediate drive shaft sprocket and crankshaft sprocket. Ensure the marks are aligned vertically.
Fig 4: View Of Primary Camshaft Drive Chain, Intermediate Drive Shaft Sprocket & Crankshaft Sprocket
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5. 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 .
6. 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 5: View Of Camshaft Intermediate Sprocket Retaining Bolt
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NOTE: Refer to Fastener Notice .
7. 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 6: View Of Primary Camshaft Drive Chain Guide
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8. Install the primary camshaft drive chain guide.
9. 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 7: Collapsing Primary Camshaft Drive Chain Tensioner
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10. 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.
11. 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 8: View Of Primary Camshaft Drive Chain Tensioner
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IMPORTANT: Ensure the primary camshaft drive chain tensioner release lever is facing out.
12. Install the primary camshaft drive chain tensioner.
13. Install the primary camshaft drive chain tensioner bolts.

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

14. Remove the pin in the release lever locking the primary camshaft drive chain tensioner.
Fig 9: Ensuring Vertical Timing Mark Alignment
Courtesy of GENERAL MOTORS CORP.
15. Ensure the timing marks (1) are aligned vertically.