Tools Required

J 42846  Crankshaft Protector Button. See Special Tools .

Fig 1: View Of Camshaft Sprocket, Timing Chain & Bolts
Courtesy of GENERAL MOTORS CORP.
1. Measure the camshaft timing chain free play. If the chain can be moved back and forth in excess of 16 mm (0.625 in), replace the chain and sprockets.
2. Remove the camshaft sprocket bolts.
3. Remove the camshaft sprocket and the timing chain.
Fig 2: Removing Crankshaft Sprocket Using J 42846
Courtesy of GENERAL MOTORS CORP.
4. Install the J 42846  (1) into the end of the crankshaft. See Special Tools .
5. Remove the crankshaft sprocket using a three jaw puller (2).