Component Tests and General Diagnostics
Pressure Test1. Turn the engine OFF.
2. WARNING: Never remove the radiator cap while the engine is operating or hot. Failure to follow these instructions can result in damage to the cooling system or engine or personal injury. To avoid having scalding hot coolant or steam blow out of the radiator when removing the cap, wait until the engine has cooled, then wrap a thick cloth around the radiator cap and turn it slowly. Step back while the pressure is released from the cooling system. When you are sure that all the pressure has been released, (with a cloth) remove the radiator cap.
Check the engine coolant level.
3. Connect the Radiator Pressure Tester to the radiator filler neck. Install a pressure test pump to the quick-connect fitting of the test adapter.
4. NOTE: If the plunger of the pump is depressed too fast, an erroneous pressure reading will result.
Slowly depress the plunger of the pressure test pump until the pressure gauge reading stops increasing and note the highest pressure reading obtained.
5. CAUTION: If the pressure drops, check for leaks at the engine to heater core hoses, engine-to-radiator hoses, coolant valve hose (if applicable), radiator and heater core or other system components and connections. Any leaks which are found must be corrected and the system rechecked.
Pressurize the engine cooling system as described in Step 4. Observe the gauge reading for approximately 2 minutes. Pressure should not drop during this time.
6. Using the pressure release feature on the Radiator Pressure Tester, release the system pressure. Check the engine coolant level and replenish, if necessary, with the correct engine coolant mixture.