How do you remove the heater core on a 1985 Chevrolet caprice?

Answer 1

The following description is for vehicles equipped with factory A/C. Procedure will be simillar for non A/C cars.

The heater core on all 1977 through 1990 GM B-Bodies is located under the hood, NOT under the dash. It was not moved to the inside of the car until 1991. To remove the heater core you will need to remove the blower motor, the rear hood weather strip, the cowl screen, the passenger side washer nozzle and the wiring connections for the blower motor and the blower motor resistor. Once you have removed these items there will be approximately 10 7mm (or 1/4") coarse thread screws to remove and a few 10mm bolts. Some are on the outside of the heater box, some are inside the box. BE GENTLE WHEN TRYING TO PRY THE BOX OPEN!!! They will crack in a hurry of you are too rough. Once you have removed the box top, there will be a retaining clip holding the heater core down. It may have a ground strap connected. Be sure to reconnect this strap. It reduces alternator noise in the radio. If it is still intact, be gentle with the foam that is covering the tube opening. You might want to just replace it with a new piece. A piece of soft foam car wash sponge will work well. When you reinstall the cover, be sure to replace the weather strip adhesive. If you can't find the correct stuff red rtv silicone works well (in generous portions). If you don't seal the box, YOU WILL have a wet floor every time it rains. Once you have everything buttoned up, run the vehicle with the heat on full blast until it gets to operating temperature. Check your antifreeze level and fill as needed. Caution! Never open the radiator when the cap is under pressure. You can be seriously burned.

This job should take a beginner about two careful hours. After you've done a few, you'll knock that time down to about 45 mins.

Here's a helpful trick. Grab a 6-10" scrap of 1/2 inch copper pipe to slide into both heater hoses when you remove them from the heater core. Tighten the clamps down and you will save yourself a lot of mess and you won't have to replace nearly as much anti-freeze.