Coolant Heater Replacement

Coolant Heater Replacement (4.3L Engine)

Removal Procedure
1. Drain the cooling system.





2. Disconnect the heater cord from the coolant heater (4).
3. Loosen the coolant heater bolt.
4. Remove the coolant heater from the engine block.
5. Do not score the machined surface of the hole.
6. Grasp the plug with pliers.
7. Pull the plug from the engine block.
8. Clean the core plug hole in order to remove the following substances:
^ Burrs
^ Compound
^ Paint
^ Rough spots

Installation Procedure
1. Coat the O-ring seal and the cleaned surface of the plug opening with water resistant high-temperature grease lubricant GM P/N 9985164 (Canadian P/N 10953480), or the equivalent.





Important: Avoid element contact with the inside walls of the engine block.

2. Tightly push the coolant heater (1) into the engine block.

Notice: Refer to Fastener Notice in Service Precautions.





3. Tighten the coolant heater bolt until both of the locking wings draw tightly against the inner wall of the engine block.
^ Tighten the bolt to 2 Nm (18 inch lbs.).





Notice: The heater cord must not touch the engine, hot pipes, manifold, or any moving parts. Route the cord to the left front of the engine compartment securing with tie straps as necessary to prevent damage.

4. Connect the heater cord to the coolant heater (4)
5. Fill the cooling system.
6. Inspect the cooling system for leaks.