Replacing a heater core

Tiny
RANDY AIKMAN
  • MEMBER
  • CHEVROLET BLAZER
1999 Chevrolet Blazer 4X4, 4.3 V6, 150k miles that has a bad heater core. The Haynes Manual that I have is incorrect. Please provide me with the correct method of removal
Do you
have the same problem?
Yes
No
Saturday, November 10th, 2007 AT 4:02 PM

2 Replies

Tiny
DENNYP
  • EXPERT


http://www.2carpros.com/forum/automotive_pictures/102900_heater_1.jpg



http://www.2carpros.com/forum/automotive_pictures/102900_123_1.jpg



http://www.2carpros.com/forum/automotive_pictures/102900_22222_1.jpg



http://www.2carpros.com/forum/automotive_pictures/102900_33333_1.jpg



http://www.2carpros.com/forum/automotive_pictures/102900_44444_1.jpg

Was this
answer
helpful?
Yes
No
Sunday, November 18th, 2007 AT 3:19 PM
Tiny
DENNYP
  • EXPERT
Heater/Vent Module Replacement
Removal Procedure

Remove the instrument panel. Refer to Instrument Panel (I/P) Carrier Replacement in Instrument Panel, Gauges and Console.
Drain the engine coolant. Refer to Draining and Filling Cooling System in Engine Cooling.
On vehicles with automatic climate control only, cut (1) the outer layer of the A/C evaporator and blower module in order to access the service access cover. Refer to Blower Motor and Fan Replacement.
On vehicles with automatic climate control only, remove the service access cover mounting screws.
On vehicles with automatic climate control only, remove the service access cover.
On vehicles without automatic climate control, remove the blower motor resistor. Refer to Blower Motor Resistor Replacement.
Important: Mark and use the same mounting bolt (located behind the A/C evaporator and blower module) for the heater assembly during the installation process. Other mounting bolts are longer and will obstruct the operation of the temperature door.

Remove the heat/vent module mounting bolt through the blower motor resistor or service access cover opening.

On vehicles with A/C only, remove the right wheel house panel. Refer to Wheelhouse Panel Replacement in Body Front End.
On vehicles with A/C only, raise and support vehicle. Refer to Lifting and Jacking the Vehicle in General Information.
On vehicles with A/C only, remove the front right tire. Refer to Tire and Wheel Removal and Installation in Tires and Wheels.
On the Utility only, remove the A/C evaporator and blower module heat shield screws.
On the Utility only, slide the A/C evaporator and blower module heat shield toward the front of the vehicle.
Remove the 2 lower heat/vent module mounting nuts.
On the Utility only, remove the A/C evaporator and blower module heat shield bracket.
Remove the bottom right heat/vent module mounting bolt from inside the vehicle.
Important: The heat/vent mounting stud has a flange on the inside and cannot be removed from under the hood. Stop turning the stud after the threads are off the heat/vent module.

On the Utility only, while an assistant inside the vehicle pulls the bottom right corner of the heat/vent module approximately 1 inch back, remove the 2 heat/vent module mounting studs.
On vehicles with A/C only, lower the vehicle.

On vehicles with a 2.2L engine only, remove the engine wiring harness bracket located at the rear of the intake manifold. Refer to Valve Rocker Arm Cover Replacement in Engine Mechanical - 2.2L.
Remove the heat/vent module mounting bolt located at the lower left side of the heater core to heater hose connection.
Remove the heat/vent module mounting nut located at the lower right side of the heater core to heater connection.
Important: The heat/vent mounting stud has a flange on the inside and cannot be removed from under the hood. Stop turning the stud after the threads are off the heat/vent module.

On the Utility only, loosen the heat/vent module mounting studs until the threads are free from the heat/vent module.
Disconnect all of the electrical connectors from the heat/vent module.
Disconnect all of the vacuum lines from the heater assembly.
Disconnect the heater hoses from the heater core.
Remove the heat/vent module from the vehicle.
Was this
answer
helpful?
Yes
No
Sunday, November 18th, 2007 AT 3:19 PM

Please login or register to post a reply.

Recommended Guides