Contents Wiring diagrams Section: Cooling System (Mechanical) All sections

Engine Cooling System: Diagnosis Kia Rio III

Cooling System (Mechanical) 11 illustrations ~347 words

Troubleshooting

SymptomsPossible CausesRemedy
Coolant leakageFrom the thermostat gasketCheck the mounting boltsCheck the torque of the mounting boltsRetighten the bolts and check leakage again.
Check the gasket for damageCheck gasket or seal for damageReplace gaskets and reuse the thermostat.
Cooled excessivelyLow heater performance (cool air blowed-out) Thermogauge indicates 'LOW'Visually check after removing the radiator cap.Insufficient coolant or leakage.After refilling coolant, recheck.
GDS check&Starting engineCheck DTCs Check connection of the fan clutch or the fan motor. If the fan clutch is always connected, there will be a noise at idle.Check the engine coolant sensor, wiring and connectors. Replace the components.
Remove the thermostat and inspectCheck if there are dusts or chips in the thermostat valve. Check adherence of the thermostat.Clean the thermostat valve and reuse the thermostat. Replace the thermostat, if it doesn't work properly.
Heated excessivelyEngine overheated Thermogauge indicates 'HI'Visually check after removing the radiator cap.Insufficient coolant or leakage. Be careful when removing a radiator cap of the overheated vehicle. Check air in cooling system.After refilling coolant, recheck. Check the cylinder head gaskets for damage and the tightening torque of the mounting bolts.
GDS check&Starting engineCheck DTCs Check the fan motor performance as temperature varies. Check if the fan clutch slips. Check the water pump adherence or impeller damaged.Check the engine coolant sensor, wiring and connectors. Check the fan motor, the relay and the connector. Replace the fan clutch, if it doesn't work properly. Replace the water pump, if it doesn't work properly.
Immerse the thermostat in boiling water and inspection.After removing the thermostat, check it works properly. Check the thermostat opens at the valve opening temperature.Replace the thermostat, if it doesn't work properly.

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Scheme 14: Water Pump

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Scheme 17
  1. Drain engine coolant. WARNING: System is under high pressure when the engine is hot. To avoid danger of releasing scalding engine coolant, remove the cap only when the engine is cool.
  2. Loosen the alternator tension adjusting bolt (A) to loosen tension.
  3. Remove the drive belt (A).
  4. Remove the water pump pulley (A). Tightening torque: 9.8 ~ 11.8 N.m (1.0 ~ 1.2 kgf.m, 7.2 ~ 8.7 lb-ft) CAUTION: Tighten the bolts diagonally when installing.
  5. Remove the water pump (A). Tightening torque: 9.8 ~ 11.8 N.m (1.0 ~ 1.2 kgf.m, 7.2 ~ 8.7 lb-ft) NOTE: Install the water pump with a new gasket.
  6. To install, reverse the removal orders.
  7. Fill with engine coolant.
  8. Start engine and check for leaks.
  9. Recheck engine coolant level.

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Scheme 18: Water Temperature Control Assembly

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Scheme 24
  1. Drain engine coolant.
  2. Disconnect the battery negative terminal.
  3. Remove the air duct and air cleaner assembly. (Refer to «ENGINE AND TRANSAXLE ASSEMBLY»(ref-536073-S40970354632013031400000) )
  4. Disconnect the engine coolant temperature sensor connector (A).
  5. Disconnect the radiator upper hose (A). NOTE: Install the radiator hoses as shown illustrations.
  6. Disconnect the heater hoses (A). NOTE: Install the heater hoses as shown illustrations.
  7. Remove the water temperature control assembly (B) after disconnecting the throttle body cooling hose (A). Tightening torque: 9.8 ~ 11.7N.m (1.0 ~ 1.2kgf.m, 7.2 ~ 8.7lb-ft)
  8. Remove the intake manifold. (Refer to «INTAKE AND EXHAUST SYSTEM»(ref-536078) )
  9. Remove the heater pipe (A). Tightening torque M6 bolt and nuts: 9.8 ~ 11.8N.m (1.0 ~ 1.2kgf.m, 7.2 ~ 8.7lb-ft) M8 bolt: 18.6 ~ 23.5N.m (1.9 ~ 2.4kgf.m, 13.7 ~ 17.4lb-ft)
  10. To install, reverse the removal orders.
CAUTIONClean the surface of the water temperature control assembly before installing.

Inspection

  1. Check each part for cracks, damage or wear, and replace the coolant pump assembly if necessary.
  2. Check the bearing for damage, abnormal noise and sluggish rotation, and replace the coolant pump assembly if necessary.
  3. Check for coolant leakage. If coolant leaks from hole, the seal is defective. Replace the coolant pump assembly and gasket.

Note. A small amount of "weeping" from the bleed hole is normal.