Explorer 2WD V6-245 4.0L SOHC VIN E EFI (1997)
Heater Core: Testing and Inspection
PLUGGED HEATER CORE
Check to make sure the engine coolant is at the proper level, then start the engine and let it run until it is warmed to operating temperature. Turn on
the heater, feel the inlet and outlet heater water hoses connected to the heater core. If the inlet heater water hose is hot and outlet heater water hose
is cooler, the heater core may be plugged.
Leak Test
1. Inspect for visible evidence of coolant leakage at the heater water hoses to heater core. A coolant leak at the heater water hose could follow the
heater core tube in the heater core and appear as a leak in the heater core.
2. Check the system for loose heater hose clamps. The clamps should be tightened to 2-3 N.m (18-27 lb/in).
3. If leakage is found and the hose clamps are tight, check the heater core tubes for distortion. Severe distortion of the tubes could cause leakage
at the hose connection.
Pressure Test
1. Drain the coolant from the cooling system.
2. Disconnect the heater water hoses from the heater core.
3. Install a short piece of heater water hose (approximately 4 in [10.2cm] long) on each 19.05 mm (3/4 inch) heater core coupling. Connect the
couplings to the heater core.
4. Fill the heater core and heater water hoses with water and install the plug and adapter from Radiator/Heater Core Pressure Tester in the ends.
Secure the heater water hoses, plug and adapter with hose clamps.
5. Attach Radiator/Heater Core Pressure Tester to the adapter. Close the bleed valve at the base of the gauge and pump 206 kPa (30 psi) of air
pressure into the heater core.
6. Observe the pressure gauge for a minimum of three minutes. The pressure should not drop.
7. If the pressure does not drop, no leaks are indicated.
8. If the pressure drops, check the coupling or hose connections to the core tubes for leaks. If the couplings or heater water hoses do not leak,
remove the heater core from the vehicle and bench test the heater core.
NOTE: Severe distortion of the core tubes could cause leakage at the coupling connection; repair or replace as necessary.
