Engine Cooling System - 2.4L: Removal & Installation Kia Optima III

Removal And Installation

Note. Disassembly of the thermostat would have an adverse effect, causing a lowering of cooling efficiency. Do not remove the thermostat, even if the engine tends to overheat.

Scheme 22

Scheme 23

Scheme 24

1. Drain engine coolant so its level is below thermostat.
2. Disconnect the radiator lower hose (A). NOTE: When installing radiator hoses, install as shown in illustrations.
3. Remove water inlet fitting (C), gasket (B) and thermostat (A). Tightening torque: 7.8 ~ 11.8 N.m (0.8 ~ 1.2kgf.m, 5.8 ~ 8.7 lb-ft)
4. Installation is reverse order of removal. NOTE: Install the thermostat with the jiggle valve upward.
5. Fill the engine coolant.
6. Start the engine and check for leaks.
7. Recheck the coolant level.

Scheme 25

1. Immerse the thermostat in water and gradually heat the water.
2. Check the valve opening temperature. Valve opening temperature: 82 ± 1.5°C (179.6 ± 2.7°F) Full opening temperature: 95°C (203°F) If the valve opening temperature is not as specified, replace the thermostat.
3. Check the valve lift. Valve lift : 8 mm (0.3 in.) or more at 95°C (203°F) If the valve lift is not as specified, replace the thermostat.