Tools Required

J 5825-A Crankshaft Sprocket Remover

1. Disconnect the battery negative cable assembly from the battery negative terminal. 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.
2. Remove the air cleaner intake duct. Refer to Air Cleaner (Air Intake Duct) in Engine Controls.
3. Remove the radiator. Refer to Radiator Replacement in Cooling and Radiator.
4. Remove the front cover. Refer to Engine Front Cover Replacement .
5. Remove the intake manifold. Refer to Intake Manifold Replacement .
6. Remove the pushrods and valve lifters. Refer to Valve Lifter Replacement .



7. Align the timing marks.
8. Remove the camshaft sprocket bolts.
9. Remove the camshaft sprocket and timing chain. The sprocket is a light interference fit on the camshaft. Tap the sprocket on its lower edge to loosen it.
10. Remove the crankshaft position sensor reluctor ring. Refer to Crankshaft Position Sensor Reluctor Ring Replacement .



11. Remove the crankshaft sprocket (if required). Use the J 5825-A .
12. Remove the front engine mount through bolts.

Notice: When supporting the engine to replace a mounting, raise the engine only to the height required to provide clearance for mounting removal. It may be necessary to drain the cooling system and disconnect hoses to avoid damage when the engine is raised. Be careful that control linkage and wiring are not damaged from raising the engine. When replacing a single front mounting, both mountings, should be detached before attempting to raise the engine. Failure to do this will place excessive stress on the attached mounting when the engine is raised.

13. Raise the engine.
14. Remove the camshaft retainer plate and bolts.



15. Remove the camshaft using the following procedure:

15.1.

Install two or three 5/16-18 bolts x 100-125 mm (4-5 in) long into the camshaft threaded holes. Use these bolts as a handle for the camshaft.

15.2.

Pull the camshaft from the block. Use care to prevent damage to the camshaft bearings.

Tools Required

J 5590 Crankshaft Sprocket Installer

1. Coat the camshaft lobes and journals with a high viscosity oil containing zinc GM P/N 12345501 or equivalent.



2. Install two or three 5/16-18 bolts 100-125 mm (4-5 in) long into the camshaft threaded holes. Use these bolts as a handle for the camshaft.
3. Install the camshaft to the engine. Handle the camshaft carefully to prevent damage to the camshaft bearings.
4. Install the camshaft retainer plate and bolts.
5. Lower the engine.
6. Install the engine mount through-bolts.

Tighten
Tighten the through-bolts to 59 N·m (44 lb ft).

Notice: 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.

7. Install the crankshaft position sensor reluctor ring. Refer to Crankshaft Position Sensor Reluctor Ring Replacement .



8. Install the crankshaft sprocket (if removed). Use the J 5590 . Make sure the timing mark faces outside.

Important: Line up the timing marks on the camshaft sprocket and crankshaft sprocket.




9. Install the camshaft sprocket and timing chain.
10. Install the camshaft sprocket bolts.

Tighten
Tighten the bolts to 28 N·m (21 lb ft).

Important: Replace all valve lifters, change the engine oil and filter, and add High Viscosity Oil with Zinc GM P/N 12345501 or the equivalent when a new camshaft is installed.

11. Install the valve lifter and pushrods. Refer to Valve Lifter Replacement .
12. Adjust the valves. Refer to Valve Lash Adjustment .
13. Install the intake manifold. Refer to Intake Manifold Replacement .
14. Install the front cover. Refer to Engine Front Cover Replacement .
15. Install the valve rocker arm covers. Refer to Valve Rocker Arm Cover Replacement .
16. Install the radiator. Refer to Radiatior Replacement in Engine Cooling.
17. Install the air cleaner intake duct. Refer to Air Cleaner (Air Intake Duct) in Engine Controls.
18. Connect the battery negative cable assembly to the battery negative terminal.

Tighten
Tighten the bolt to 15 N·m (11 lb ft).

19. Fill the cooling system with the proper quantity and grade of coolant. Refer to Draining and Filling Cooling System in Engine Cooling.