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For 1990-2009 cars only

Cooling System Leak Testing 3800 V6 L36

Leak Testing

  1. Add water to the radiator to detect core leaks. Clean the core in order to make it easier to find the damaged area.
  2. Remove dirt and insects from the fins with a common water hose without a nozzle. Excessive water pressure could damage the fins.
  3. Scrub the core with a soft-bristle brush. Use clean hot water or hot water with a mild detergent solution.

On-Vehicle Testing

Tools Required

J 24460-01 Cooling System Tester

  1. Pressure test the aluminum/plastic radiator using a common pump and gage.
  2. Make sure the cooling system is at a cool temperature, then remove the radiator cap.

  3. Object Number: 11658  Size: SH
  4. Connect the gage and apply normal system operating pressure. Do not exceed 138 kPa (20 psi).
  5. Watch the gage needle for an indication of a leak.
  6. Examine the radiator and other cooling system parts for signs of escaping coolant.
  7. Repair all hose and hose connections as required.
  8. Check the radiator cap to ensure that it will maintain the correct pressure.
  9. If the radiator is leaking during the pressure test, mark the leak area in order to find the leak once the radiator is removed.

Off-Vehicle Testing

Notice: Never use compressed air to pressure test a radiator that is not regulated to 138 kPa (20 psi). Pressures over 138 kPa (20 psi.) will damage the radiator.

Do not use the boil-out tanks or vats or other tanks that have been used for copper and brass radiators. The flux, acid and caustic cleaners remaining in these tanks will attack the aluminum and cause radiator failure. A separate test tank containing clean water is strongly recommended for servicing an aluminum/plastic radiator.


Object Number: 162205  Size: SH
  1. Install the test fittings or rubber test caps in the inlet and outlet necks and seal the oil cooler footings with metal plugs. This will protect the cooler and keep the fluid from running out.
  2. Attach the pressure tester and gradually apply air pressure.
  3. • Do not exceed 138 kPa (20 psi).
    • Check pressure gage to see if there is a pressure loss.
    • To ensure that there are no small leaks, run water over the repair area and look for bubbles. (A mild detergent is very helpful.)
    • If a large water tank is available, submerge the radiator and check for bubbles at the following locations:
       - Inlet tank (1)
       - Core tubes (2)
       - Outlet tank (3)
       - Oil cooler connections (4)
       - Drain plug (5)

Cooling System Leak Testing 3.5L V6 LX5

Leak Testing Procedure (On Vehicle)

Tools Required

    • J 24460-01 Cooling System Tester
    • J 24460-92 Surge Tank Test Adapter

    Object Number: 179282  Size: SH

    Caution: Under pressure, the temperature of the solution in the radiator can be considerably higher, without boiling. Removing the radiator cap while the engine is hot (pressure is high), will cause the solution to boil instantaneously, with explosive force. The solution will spew out over the engine, fenders, and the person removing the cap. Serious bodily injury may result. Flammable antifreeze, such as alcohol, is not recommended for use at any time. Flammable antifreeze could cause a serious fire.

    Caution: In order to help avoid being burned, do not remove the radiator cap while the engine and the radiator are hot. Scalding fluid and steam can be blown out under pressure if the cap is removed too soon.

  1. After the system has cooled, remove the radiator/surge tank pressure cap.
  2. Connect the cooling system tester J 24460-01 and the J 24460-92 to the radiator/surge tank.
  3. Apply normal system operation pressure. Do not exceed 138 kPa (20 psi).
  4. Watch the gauge needle for an indication of a leak. Examine all cooling system connections and components, including the radiator and the heater core, for leaking coolant.
  5. Tighten the hose connections or repair as required.

  6. Object Number: 179280  Size: SH
  7. Check the radiator/surge tank cap with the J 24460  -01 and the J 24460-92 in order to ensure the cap maintains the correct pressure.
  8. If the radiator leaks during the pressure test, mark the leak area so the leak can be located once the radiator has been removed from the vehicle.