Engine Cooling System (H6DO): Diagnosis Subaru Outback BP

INSPECTION

TROUBLE SYMPTOM

Radiator main fan does not rotate in low speed under the following conditions

1. Coolant temperature 95°C (203°F) or more.
2. A/C switch set to OFF.

1. Radiator main fan does not rotate in middle speed under the following conditions: Coolant temperature 94°C (201°F) or less. A/C switch set to ON and A/C temperature at the lowest position.
2. Radiator main fan does not rotate in high speed under the following conditions: Coolant temperature 95°C (203°F) or more. A/C switch set to ON and A/C temperature at the lowest position.

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Note. Inspection by SOA (distributor) service is required, because probable cause is deterioration of multiple parts.

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TROUBLE SYMPTOM

1. Radiator sub fan does not rotate in low speed under the following conditions: Coolant temperature 95°C (203°F) or more. A/C switch set to OFF.
2. Radiator sub fan does not rotate in middle speed under the following conditions: Coolant temperature 94°C (201°F) or less. A/C switch set to ON and A/C temperature at the lowest position.
3. Radiator sub fan does not rotate in high speed under the following conditions: Coolant temperature 95°C (203°F) or more. A/C switch set to ON and A/C temperature at the lowest position.

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Note. Inspection by SOA (distributor) service is required, because probable cause is deterioration of multiple parts.

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1. Lift-up the vehicle.
2. Remove under cover.
3. Remove drain cock to drain engine coolant into container.

Note. Remove radiator cap so that engine coolant will drain faster.

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1. Fill engine coolant into radiator up to filler neck position. Coolant amount for refill: Approx. 7.9 ell (8.4 US qt, 7.0 Imp qt) CAUTION: The SUBARU Genuine Coolant containing antifreeze and anti-rust agents is especially made for SUBARU engine, which has an aluminum crankcase. Always use SUBARU Genuine Coolant, since other coolant may cause corrosion.
2. Fill engine coolant into reservoir tank up to upper level.
3. Attach radiator cap and reservoir tank cap properly.
4. Warm-up engine completely for more than five minutes at 2,000 to 3,000 RPM.
5. If engine coolant level drops in radiator, add engine coolant to filler neck position.
6. If engine coolant level drops from upper level of reservoir tank, add engine coolant to upper level.
7. Attach radiator cap and reservoir tank cap properly.

1. Check water pump bearing for smooth rotation.
2. Check water pump sprocket for abnormalities.

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1. Lift-up the vehicle.
2. Remove under cover.
3. Drain engine coolant completely. Refer to «ENGINE COOLANT»(ref-208387-S24314414042005120700000) .
4. Disconnect radiator outlet hose from thermostat cover.
5. Remove thermostat cover and gasket, and pull out the thermostat.

Replace the thermostat if the valve does not close completely at an ambient temperature or if the following test shows unsatisfactory results.

Immerse the thermostat and a thermometer in water. Raise water temperature gradually, and measure the temperature and valve lift when the valve begins to open and when the valve is fully opened. During the test, agitate the water for even temperature distribution. The measurement should be to the specification.

Starts to open

1. 76.0 - 80.0°C (169 - 176°F)

Fully opens

1. 91°C (196°F)

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1. Disconnect battery ground cable.
2. Lift-up the vehicle.
3. Remove under cover.
4. Drain engine coolant completely. Refer to «ENGINE COOLANT»(ref-208387-S24314414042005120700000) .
5. Disconnect connectors of radiator main fan motor (A) and sub fan motor (B).
6. Disconnect radiator outlet hose from radiator.
7. Disconnect ATF cooler hoses from radiator.
8. Lower the vehicle.
9. Remove air intake duct.
10. Disconnect over flow hose.
11. Remove reservoir tank.
12. Disconnect radiator inlet hoses from radiator.
13. Remove radiator upper brackets.
14. Detach power steering hose from the clip on the radiator.
15. While slightly lifting radiator, slide it to left.
16. Lift radiator up and away from vehicle.

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1. Attach radiator mounting cushions to holes on the vehicle.
2. Install radiator while fitting radiator pins to cushions. NOTE: Fit pins on lower side of radiator into cushions on body side.
3. Install radiator brackets and tighten bolts. Tightening torque: 12 N.m (1.2 kgf-m, 8.7 ft-lb)
4. Attach power steering hose to the radiator.
5. Connect radiator inlet hoses.
6. Install reservoir tank. Tightening torque: 4.9 N.m (0.50 kgf-m, 3.6 ft-lb)
7. Install air intake duct.
8. Lift-up the vehicle.
9. Connect ATF cooler hoses.
10. Connect connectors to radiator main fan motor (A) and sub fan motor (B).
11. Connect radiator outlet hose.
12. Install under cover.
13. Lower the vehicle.
14. Connect battery ground cable.
15. Fill coolant. Refer to «ENGINE COOLANT»(ref-208387-S24314414042005120700000) .
16. Check ATF level. Refer to «INSPECTION»(ref-208395-S08573280712005120700000) , Automatic Transmission Fluid.

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1. Remove radiator cap, top off radiator, and attach tester to radiator in place of cap.
2. Apply a pressure of 157 kPa (1.6 kg/cm2, 23 psi) to radiator to check if: Engine coolant leaks at/around radiator. Engine coolant leaks at/around hoses or connections.

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1. Attach radiator cap to tester.
2. Increase pressure until tester gauge pointer stops. Radiator cap is functioning properly if it holds the service limit pressure for five to six seconds.

Standard pressure

1. 93 - 123 kPa (0.95 - 1.25 kg/cm2, 14 - 18 psi)

1. Service limit pressure
2. 83 kPa (0.85 kg/cm2, 12 psi)

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1. Disconnect battery ground cable.
2. Lift-up the vehicle.
3. Remove under cover.
4. Drain engine coolant completely. Refer to «ENGINE COOLANT»(ref-208387-S24314414042005120700000) .
5. Disconnect connectors of main and sub fan motor.
6. Lower the vehicle.
7. Remove air intake duct.
8. Disconnect over flow hose.
9. Remove reservoir tank.
10. Disconnect radiator inlet hoses from radiator.
11. Remove radiator sub fan motor assembly.
12. Remove radiator main fan motor assembly. NOTE: When removing main fan assembly by lifting it upward, main fan shroud will cause interference with coolant suction area. In order to avoid this, shift the main fan assembly over to sub fan side before removing it.

Make sure the engine coolant level is between full and low.

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