Pressure Testing Cooling System

CAUTION: Explosive release of fluids from pressurized cooling system can cause serious burns.

Shut off engine. Remove filler cap only when cool enough to touch with bare hands. Slowly loosen cap to first stop to relieve pressure before removing completely.

Test Radiator Cap

1. 
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   Attach Radiator Cap to Tester

   Remove radiator cap and attach to an approved tester as shown.

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2. Refer to vehicle operator's manual for correct test pressures. Gauge should hold pressure for 10 seconds within the normal range if cap is acceptable.

3. Remove the cap from gauge, turn it 180°, and retest cap. This will verify that the first measurement was accurate.

4. If gauge does not hold pressure, replace radiator cap.

Test Cooling System

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Test Cooling System

NOTE: Engine should be warmed up to test overall cooling system.

1. Allow engine to cool, then carefully remove radiator cap.

2. Fill radiator with coolant to the normal operating level.

3. IMPORTANT: DO NOT apply excessive pressure to cooling system. Doing so may damage expansion tank and hoses.

   Connect gauge and adapter to expansion tank filler neck. Pressurize cooling system to specifications found in vehicle operator's manual.

4. With pressure applied, check all cooling system hose connections, radiator, and overall engine for leaks.

5. If leakage is detected, correct as necessary and pressure test system again.

6. If no leakage is detected, but the gauge indicated a drop in pressure, coolant may be leaking internally within the system or at the block-to-head gasket. Have your engine servicing dealer correct this problem immediately.