Heater Core (Auxiliary System)
HEATER CORE LEAK TESTHeater core leaks can be indicated by wet carpeting and coolant odor in the passenger compartment
An inadequate seal between the heater core tubes can allow coolant to follow the tube to the heater core and appear as a leak. If a heater core leak is suspected, use the following procedures.
1. Look for evidence of coolant leakage at the heater water hose-to-heater core attachments.
2. Check the system for loose heater hose clamps.
3. If a leak is found and the hose clamps are tight, check the heater core tubes for distortion or evidence of being bent out of shape. Severe distortion of the heater core water tubes could cause leakage at the heater water hose connection.
IN-VEHICLE PRESSURE TEST
Use Rotunda Radiator/Heater Core Pressure Tester 014-R1052 or equivalent to perform pressure test.
1. Drain the coolant from the cooling system.
2. Disconnect the heater water hose from the heater core tubes.
3. Install a short piece of heater water hose approximately 102 mm (4 inches) long on each heater core tube.
4. Fill the heater core and heater water hoses with water and install Plug in one hose end and Adapter from Rotunda Radiator/Heater Core Pressure Tester 014-R1052 or equivalent in the other hose end. Secure the heater water hoses, plug and adapter with hose clamp tightened to 1.7-2.4 N.m (16-21 lb-in).
5. Attach the pump and gauge assembly from Rotunda Radiator/Heater Core Pressure Tester 014-R1052 or equivalent to the adapter.
6. Close the bleed valve at the base of the gauge and pump 103 kPa (15 psi) of air pressure into the heater core.
7. Observe the pressure gauge for a minimum of three minutes. The pressure should not drop.
8. If the pressure does not drop, no leaks are indicated.
9. If the pressure drops, check the hose connections to the heater core tubes for leaks. It the hoses do not leak, remove the heater core from the vehicle and perform the Bench Pressure Test.
BENCH PRESSURE TEST
1. Drain all coolant from the heater core.
2. Remove heater core from the auxiliary A/C evaporator housing.
3. Connect the 102 mm (4 inch) test heater water hoses with plug and adapter to the core tubes. Then connect the Rotunda Radiator/Heater Core Pressure Tester 014-R1052 or equivalent to the adapter.
4. Apply 103 kPa (15 psi) of air pressure to the heater core. Submerge the heater core in water.