Installation Procedure

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If reusing the old coolant heater, apply sealant GM P/N 12346004, (Canadian P/N 10953480), or equivalent to the threads.
NOTE: Refer to FASTENER NOTICE in Cautions and Notices.
Install the coolant heater into the engine block.
Tighten

Tighten the coolant heater to 60 N.m (40 lb ft).

Fig 1: Installing Coolant Heater Into Engine Block
Courtesy of GENERAL MOTORS CORP.

NOTE: 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.
Connect the coolant heater electrical connector.
Fill the cooling system/engine block. Refer to DRAINING AND FILLING COOLING SYSTEM .

Fig 2: Connecting Coolant Heater Electrical Connector
Courtesy of GENERAL MOTORS CORP.