Cooling System: Inspection

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 kgf/cm2, 23 psi)

Turbo model:

122 kPa (1.2 kgf/cm2, 18 psi)
- Each portion of radiator for leakage
- Hose joints and other connections for leakage
CAUTION: If the engine coolant adheres to the exhaust pipe, wipe it off completely.
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 To Filler Neck - Non-TURBO Model
    Courtesy of SUBARU OF AMERICA, INC.
  - Turbo model
  Fig 2: Identifying Radiator Cap Tester - Turbo Model
  Courtesy 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)
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. The radiator cap is normal if the pressure keeps to be the same as or above the limit. Replace the radiator cap if the pressure is below the limit.

Radiator cap valve open pressure

Non-turbo model

Standard:

93 - 123 kPa

(0.95 - 1.25 kgf/cm2, 14 - 18 psi)

Service limit:

83 kPa (0.85 kgf/cm2, 12 psi)

Turbo model

Filler tank side

Standard:

93 - 123 kPa

(0.95 - 1.25 kgf/cm2, 14 - 18 psi)

Service limit:

83 kPa (0.85 kgf/cm2, 12 psi)

Radiator side

Standard:

122 - 152 kPa

(1.24 - 1.55 kgf/cm2, 18 - 22 psi)

Service limit:

112 kPa (1.14 kgf/cm2, 16 psi)

Fig 3: Checking Radiator Cap Valve Open Pressure
Courtesy of SUBARU OF AMERICA, INC.

Fig 4: Identifying Points For Deformation, Damage, Rust
Courtesy of SUBARU OF AMERICA, INC.
Start the engine, and then inspect that it does not overheat or it is cooled excessively. If it overheats or it is cooled excessively, check the cooling system.
- Non-turbo model
  <Ref. to WATER PUMP , Water Pump.>, <Ref. to THERMOSTAT , Thermostat.>, <Ref. to RADIATOR , Radiator.>, <Ref. to RADIATOR CAP , Radiator Cap.>
- Turbo model
  <Ref. to WATER PUMP .>, <Ref. to THERMOSTAT .>, <Ref. to RADIATOR .>, <Ref. to RADIATOR CAP .>
- STI model
  <Ref. to WATER PUMP .>, <Ref. to THERMOSTAT .>, <Ref. to RADIATOR .>, <Ref. to RADIATOR CAP .>
- Check the radiator fan operates using Subaru Select Monitor, when the coolant temperature rise to 95°C (203°F) or more. If it does not operate, check the radiator fan system.
Non-turbo model
<Ref. to RADIATOR MAIN FAN SYSTEM , Radiator Main Fan Systems.> <Ref. to RADIATOR SUB FAN SYSTEM , Radiator Sub Fan System.>
Turbo model
<Ref. to RADIATOR MAIN FAN SYSTEMS .> <Ref. to RADIATOR SUB FAN SYSTEM .>
STI model
<Ref. to RADIATOR MAIN FAN SYSTEM .>, <Ref. to RADIATOR SUB FAN SYSTEM .>