How do you replace the heater core in a 1994 GMC Jimmy?

Question

Do I also have to do a coolant flush? I need the entire procedure. Thanks.

Answer 1

you dont have to do a coolant flush but i do recommend it, first you need to drain the coolant from the system and dispose of it properly, then you need to follow your heater lines into the bulkhead and diconnect them from the engine compartment side, then in cab you need to find the heater box behind the dash and remove it you may need to remove part of the dash to access it remove the box and heater core and replace the heater core installation will be revers of removal, sorry i wasnt more specific it has been a while since i have done a heater core on a jimmy

Answer 2

When looking into the engine compartment you should see the location of the heater hoses. these connect to the heater core. These need to be disconnected first, after you lower the coolant level in the radiator. Any spilled antifreeze should be cleaned up immediately as it is toxic to cats and dogs. Once this is done then locate the modular vent on the lower inside of the truck cab. This is where the heat and cool air comes out on the floor level. For more pictures try your local library auto reference books. they may have one you need or can get it for you.

Answer 3

Drain the antifreeze, take off the hood, unplug the heater blower, and take off the heater core cover. Believe me taking off the hood will take hours off the procedure. You dont necessarily have to take off the hood but it will save time and cussing. After removing the hoses from the heater core, and taking off the cover, the heater core should slip right out. Put the new one in and reverse the process to put it back together.

Answer 4

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