Water Pump Coolant Leak Check

If a residue of the coolant draining is found on the drain hole, the vapor hole and the installation surface, check the water pump leakage by following method.

1. Wipe off the residue of the coolant draining on the water pump.
   WARNING: Make sure that the coolant is cold when removing the radiator cap.
2. Remove the radiator cap.
   CAUTION: Do not pressures 100 kPa (15 psi) or more.
3. Install the radiator tester and pressures at 100 kPa (15 psi.)
4. Hold the pressurized state for 20 minutes, and check that the water leakage from the drain hole, the vapor hole or the installation surface of the water pump.
5. Remove the radiator tester, and install the radiator cap.
6. Warm up the engine, let it idle for 20 minutes and stop it.
7. After stopping the engine, and check that the water leakage from the drain hole, the vapor hole or the installation surface of the water pump.
8. If the water leakage is found in step  4 or  7, replace the water pump (Refer to REMOVAL AND INSTALLATION < 2.0L ENGINE NON-TURBO, 2.4L ENGINE >  ) or (Refer to REMOVAL AND INSTALLATION < 2.0L ENGINE TURBO >  ).
   Fig 1: Installing Radiator Tester To Filler Neck

   Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.