1. Depressurize the fuel system. Refer to Fuel System Pressure Relief in Engine Fuel.
2. Disconnect the negative battery cable. Refer to

   Caution: Unless directed otherwise, the ignition and start switch must be in the OFF or LOCK position, and all electrical loads must be OFF before servicing any electrical component. Disconnect the negative battery cable to prevent an electrical spark should a tool or equipment come in contact with an exposed electrical terminal. Failure to follow these precautions may result in personal injury and/or damage to the vehicle or its components.

   in General Information.
3. Drain the engine coolant. Recover the engine coolant. Refer to Draining, Flushing and Filling the Cooling System in Cooling and Radiator.
4. Remove the engine. Refer to Engine Replacement .
5. Remove the valve lifters. Refer to Valve Lifter Replacement .
6. Remove the crankcase front cover. Refer to Engine Front Cover Replacement .
7. Remove the timing chain and the sprocket. Refer to Timing Chain and Sprocket Replacement .

Notice: All camshaft journals are the same diameter, so care must be used in removing or installing the camshaft to avoid damage to the camshaft bearings.




8. Remove the camshaft thrust plate bolts.
9. Remove the camshaft thrust plate.



10. Remove the camshaft. Use the following procedure:

10.1.

Install a camshaft bolt into the camshaft bolt hole in order to support the camshaft.

10.2.

Carefully, rotate the camshaft. Pull the camshaft out of the cam bearings.

Important: Whenever a new camshaft is installed, coat the camshaft lobes with GM E.O.S. P/N 10523675 or equivalent.

Notice: All camshaft journals are the same diameter, so care must be used in removing or installing the camshaft to avoid damage to the camshaft bearings.

1. Coat the camshaft journals with engine oil or its equivalent.



2. Install the camshaft.



3. Install the camshaft thrust plate.
4. Install the camshaft thrust plate bolts.
5. Install the timing chain and the sprocket. Refer to Timing Chain and Sprocket Replacement .
6. Install the crankcase front cover. Refer to Engine Front Cover Replacement .
7. Install the valve lifters. Refer to Valve Lifter Replacement .
8. Install the engine. Refer to Engine Replacement .
9. Fill the cooling system. Refer to Draining, Flushing and Filling the Cooling System in Cooling and Radiator.
10. Connect the negative battery cable.