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Cooling System: Inspection

  1. To check the radiator for leakage, fill it with engine coolant, and attach the radiator cap tester (A) to the filler neck, and apply pressure. Check the following points:

    Non-turbo model: 

    157 kPa (1.6 kg/cm 2  , 23 psi) 

    Turbo model: 

    122 kPa (1.2 kg/cm 2  , 18 psi) 

    • Each portion of radiator for leakage
    • Hose joints and other connections for leakage
    NOTE:
    • For turbo model, be sure to install the tester to filler tank side.
    • Be particularly careful not to deform the filler neck of radiator when installing and removing the tester and after testing.
    • Non-turbo model
      Fig 1: Identifying Radiator Cap Tester (Non-Turbo Model)
      G04997265Courtesy of SUBARU OF AMERICA, INC.
      • Turbo model
        Fig 2: Identifying Radiator Cap Tester (Turbo Model)
        G05019594Courtesy of SUBARU OF AMERICA, INC.
    • When performing this check, be sure to keep the engine stationary and fill radiator with coolant.
    • Wipe off check points before applying pressure.
    • Use care not to spill coolant when detaching tester from radiator.
    • Do not remove the radiator side cap. (Turbo model)
  2. Check the radiator cap valve open pressure using radiator cap tester.
    NOTE: Rust or dirt on the cap may prevent valve from functioning normally: be sure to clean the cap before testing.

    Raise the pressure until the needle of gauge stops and see if the pressure can be retained for five to six seconds. Replace the radiator cap if it is opened under a pressure less than the service limit value for this period.

    Radiator cap valve open pressure 

    Non-turbo model 

    Standard: 

    93 - 123 kPa(0.95 - 125 kg/cm 2  , 14 - 18 psi) 

    Service limit: 

    83 kPa (0.85 kg/cm 2  , 12 psi) 

    Turbo model 

    Filler tank side 

    Standard: 

    93 - 123 kPa (0.95 - 125 kg/cm 2  , 14 - 18 psi) 

    Service limit: 

    83 kPa (0.85 kg/cm 2  , 12 psi) 

    Radiator side 

    Standard: 

    122 - 152 kPa(124 - 1.55 kg/cm 2  , 18 - 22 psi) 

    Service limit: 

    112 kPa (1.14 kg/cm 2  , 16 psi) 

    Fig 3: Checking Radiator Cap Valve Open Pressure
    G04997267Courtesy of SUBARU OF AMERICA, INC.
    • 2.5 L model 
      Fig 4: Identifying Radiator Cap Valve Check Points (2.5 L Model)
      G05664895Courtesy of SUBARU OF AMERICA, INC.
    • 3.0 L model 
      Fig 5: Identifying Radiator Cap Valve Check Points (3.0 L Model)
      G05664896Courtesy of SUBARU OF AMERICA, INC.
  3. Start the engine, and then check it does not overheat or it is cooled excessively. If it overheats or it is cooled excessively, check the cooling system.
    CAUTION: If the engine coolant is spilt over exhaust pipe, wipe it off with cloth to avoid emitting smoke or causing a fire.
    • 2.5 L non-turbo model

    <Ref. to WATER PUMP . > <Ref. to THERMOSTAT . > <Ref. to RADIATOR . > <Ref. to RADIATOR CAP . >

    • 2.5 L turbo model

    <Ref. to WATER PUMP . > <Ref. to THERMOSTAT . > <Ref. to RADIATOR . > <Ref. to RADIATOR CAP . >

    • 3.0 L model

    <Ref. to WATER PUMP . > <Ref. to THERMOSTAT . > <Ref. to RADIATOR . > <Ref. to RADIATOR CAP . >

  4. Check the radiator fan operates using Subaru Select Monitor, when the coolant temperature exceeds 96°C (205°F). If it does not operate, check the radiator fan system.
    • 2.5 L non-turbo model

      <Ref. to INSPECTION , Radiator Fan System .>

    • 2.5 L turbo model

      <Ref. to INSPECTION , Radiator Fan System .>

    • 3.0 L model

      <Ref. to INSPECTION , Radiator Fan System .>