Component Tests and General Diagnostics

1. Turn the engine off.

2. Check engine coolant level.

WARNING: NEVER REMOVE THE PRESSURE RELIEF CAP UNDER ANY CONDITIONS WHILE THE ENGINE IS OPERATING. FAILURE TO FOLLOW THESE INSTRUCTIONS COULD RESULT IN DAMAGE TO THE COOLING SYSTEM OR ENGINE AND/OR PERSONAL INJURY. TO AVOID HAVING SCALDING HOT COOLANT OR STEAM BLOW OUT OF THE COOLING SYSTEM, NEVER REMOVE THE PRESSURE RELIEF CAP FROM A HOT DEGAS BOTTLE. WAIT UNTIL THE ENGINE HAS COOLED, THEN WRAP A THICK CLOTH AROUND THE PRESSURE RELIEF CAP AND TURN IT SLOWLY ONE TURN (COUNTERCLOCKWISE). STEP BACK WHILE THE PRESSURE IS RELEASED FROM THE COOLING SYSTEM. WHEN CERTAIN ALL THE PRESSURE HAS BEEN RELEASED, REMOVE PRESSURE RELIEF CAP (STILL USING A CLOTH).





3. Connect Rotunda Radiator/Heater Core Pressure Tester 014-R1072 or equivalent to degas bottle nipple and de-aeration hose. Install pressure test pump to the quick-connect fitting of the test adapter.

4. Slowly depress the plunger of the pressure test pump until the pressure gauge reading stops increasing and note the highest pressure reading obtained

NOTE: If the plunger of the pump is depressed too fast, an erroneous pressure reading will result.

5. If the pressure relief cap does not hold pressure, remove and wash the pressure relief cap in clean water to dislodge all foreign particles from the gaskets. Check the sealing surface in the filler neck.
6. If 89 kPa (13 psi) cannot be reached, replace pressure relief cap. If more than 12 kPa (18 psi) shows on gauge replace pressure relief cap.
7. Pressurize the engine cooling system as described in Step 4 (using a pressure relief cap that operates within the specified upper and lower pressure limits). Observe the gauge reading for approximately two minutes. Refer to Specifications. Pressure should not drop during this time.

If the system holds pressure, proceed to Step 8.

CAUTION: If the pressure drops, check for leaks at the engine to heater core hoses, engine-to-radiator hoses, water valve hose (if applicable), water hose connection gasket, radiator and heater core or other system components and connections. Any leaks which are found must be corrected and system rechecked.

8. Release system pressure by loosening the pressure relief cap. Check engine coolant level and replenish, if necessary, with the correct engine coolant mixture.