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Pressure Test: Notes

WARNING: This page is about a different car, the 2003 Lincoln Aviator. However, it is still accessible from the selected car via links, so may be relevant.
  1. Turn the engine off.
    2. WARNING: Never remove the pressure relief 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 degas bottle when removing the pressure relief cap, wait until the engine has cooled, then wrap a thick cloth around the pressure relief 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, (still with a cloth) remove the pressure relief cap.
  2. Check the engine coolant level. For additional information, refer to COOLING SYSTEM DRAINING, FILLING AND BLEEDING .
  3. Connect the Radiator Heater Core Pressure Tester to the degas bottle nipple and overflow hose. Install a pressure test pump to the quick-connect fitting of the test adapter.
    4. NOTE: If the plunger of the pump is pressed too fast, an erroneous pressure reading will result.
  4. Slowly press 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, water valve hose (if applicable), oil cooler return tube gasket, radiator and heater core, or other system components and connections. Any leaks that are found must be corrected and the system rechecked.
  5. 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. For additional information, refer to SPECIFICATIONS . Pressure should not drop during this time.
  6. Release the system pressure by loosening the pressure relief cap. Check the engine coolant level and replenish, if necessary, with the correct engine coolant mixture. For additional information, refer to COOLING SYSTEM DRAINING, FILLING AND BLEEDING .
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