Kia Optima: Removal and Installation - Thermostat. Repair procedures - Cooling System - Engine Mechanical System - Kia Optima TF 2011-2026 Service ManualKia Optima: Removal and Installation

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.
1. Drain engine coolant so its level is below thermostat.
2. Disconnect the radiator lower hose (A).

3. Remove water inlet fitting (C), gasket (B) and thermostat (A).

Tightening torque :

7.8 ~ 11.8N.m (0.8 ~ 1.2kgf.m, 5.8 ~ 8.7lb-ft)


4. Installation is reverse order of removal.
Install the thermostat with the jiggle valve upward.
When assembling the thermostat, place the thermostat on the housing with a protrusion of thermostat matching with a groove of the housing and install the gasket and inlet fitting. Be careful the thermostat doesn’t get out of the groove on the housing.
5. Fill the engine coolant.
6. Start the engine and check for leaks.
7. Recheck the coolant level.

Thermostat. Repair procedures
...

Inspection
1. Immerse the thermostat in water and gradually heat the water. 2. Check the valve opening temperature. Valve opening temperature: 82 ± 1.5°C ( ...

See also:

Installation
1. Installation is the reverse of removal. • When installing, apply the ATF oil or white vas ...

Description and Operation
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Checking the Coolant Level
WARNING - Removing Radiator Cap Never attempt to remove the radiator cap while the engine is operating. Doing so might lead to cooling system and engine damage and could result in serio ...

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