Q: How to replace the Heater Core on 1987 and later Mercury Capri?
A: Remove the center console and instrument panel. If the vehicle is air conditioned, disconnect the liquid line and accumulator/receiver-drier inlet tube from the evaporator core at the dash panel. Disconnect the high and low pressure hoses, cap the hoses, line and tube to keep out dirt and moisture. Drain the cooling system and detach the heater hoses from the heater core at the firewall, cap or plug the hoses. Remove the screw that secures the air inlet duct/blower housing assembly to the cowl top panel. Working in the engine compartment, disconnect the black heater vacuum supply hose from the inline check valve. Remove the two heater case stud nuts from the engine compartment side of the firewall. Working in the passenger compartment, disconnect the blower motor electrical connector from the motor and resistor block, disconnect the blower motor ground wire. On vehicles without air conditioning, remove the screw that secures the heater case support bracket to the cowl top panel. On vehicles with air conditioning, remove the two screws that secure the evaporator case support brackets to the cowl top panel. Remove the remaining screw that secures the lower part of the heater case to the dash panel. Carefully pull the heater case away from the dash panel and withdraw it into the passenger compartment. Remove the screws from the heater core cover, lift the cover off and remove the heater core and seal from the case. If necessary, take the seal off of the heater core tubes. Installation is the reverse of removal. Run the engine, check for leaks and test the heater.
Q: How can you replace the heater core without air conditioning on 1979 through 1986 Mercury Capri?
A: Without air conditioning, you can remove the heater core by partially draining the cooling system and loosening the clamps on the heater hoses. Twist and separate the hoses from the heater core tubes, and plug or cap the tubes to prevent coolant spills. Place a plastic sheet on the vehicle floor for protection. Remove the glovebox liner and instrument panel-to-cowl brace. Set the temperature lever to Warm and remove the heater core cover through the glovebox opening. Loosen the three stud nuts in the engine compartment to detach the heater core from the heater case. Pull the heater core through the glovebox opening and position it with the tubes on top. Slide it back into the heater case and secure the heater core cover. Tighten the stud nuts, reinstall the instrument panel-to-cowl brace, and replace the glovebox liner. Uncap or unplug the heater core tubes and reconnect the hoses. Finally, fill the cooling system, check for leaks, and test the heater.
A: The heater circulates engine coolant through a small radiator (heater core) in the passenger compartment. Air is drawn in through an opening in the cowl, then blown through the heater core by the Blower Motor to pick up heat. The heated air is blended with varying amounts of unheated air to regulate its temperature. The heated air is then blown into the passenger compartment. Various doors in the heater control the flow of air to the floor, instrument panel, and defroster outlets.