How do you replace the heater core on a 1985 Buick LeSabre Special Edition rear wheel drive with 8 cylinder?

Answer 1

I own a 1985 LeSabre 2 dr, and last winter the heater core went. Replacement is very easy when compared to other car makes.

The heater core is located under the hood on the passenger side. Make sure that the engine is cold before doing this.

1. Start by removing the heater inlet and outlet hoses. They are quite obvious, as they go directly into the firewall. Make sure to have a catch can or container to catch the coolant when it comes out.

2. Disconnect any other wires, hoses or mines running to the heater core case. This includes the blower motor resistor pack, which has a big plastic conncector attached to it.

3. Remove the cowl weather stripping and the leaf guard that is located just under the windshield. Also, remove the windshield washer supply hose if necessary.

4. Remove the twelve or so screws from the top of the heater case. Alos, at this time disconnect the A/C switching valve soelnoid on the back of the reciver-drier (Looks like a big verticle tank coming out of the heater core case, the solenoid connector just unhooks), only if the vehicle has A/C.

5. Lift off the top of the heater case. You do not have to remove the blower assembly. Alos, you will have to cut the seal around the base of the windshield that seals out water from the heater case.

6. Lift out the old heater core assembly. Install the new one, making sure that the protrusion on the bottom of the new heater core fits sngly into the molded part of the heater case.

7. Install top of heater case and seal the part of the case near the windshield with RTV or even black window caulk. Balance of installation is reverse of removal. Besure to refill cooling system with heater in the "HOT" position and make sure all the concections (ie, vacuum lines, windshield fittings and electrical connectors) are all secure.