How to Install a Heater Core in a 1998 Jeep Wrangler
- 1). Recover the refrigerant from the air-conditioning system by taking the vehicle to an auto dealership or service center for evacuation of freon. Do not attempt to disconnect the fittings of the system until the refrigerant has been removed because it is under high pressure.
- 2). Remove the negative cable from the battery. Open the drain fitting on the radiator and drain the coolant from the system into a disposal container. Once empty, move the container beneath the engine block, loosen the drain plugs and let any remaining coolant drain into the disposal container.
- 3). Raise the hood and remove the hoses going into the inlet and outlet of the heater core, the refrigerant lines at the firewall, the heater control cables and the defroster duct by loosening the hose clamps. Remove the all screws of the instrument panel with a screwdriver. Pull out at the top of the individual panel pieces to remove them. Then, pull out on the instrument panel to detach the instrument panel from the dashboard. The heater core will be located behind the shifter core.
- 4). Remove the nuts from the studs on the engine compartment side of the firewall for the heater core housing attachment. Pull and tilt the heater core housing down. Remove the heater core's retaining screws on the housing assembly and then remove it from the vehicle by pulling it from the housing.
- 5). Replace the heater core and install the previously removed parts in reverse order. Ensure the heater core's housing studs are inserted through the firewall.
- 6). Add coolant to the radiator and reservoir until full. Start the engine and verify the heating system works properly. Be careful not to turn the air-conditioning system on until refrigerant has been added back to the system.
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