3.
Disconnect the radiator upper hose (A).
Disassembling the thermostat may have an adverse effect, causing degraded cooling efficiency.
Drain the engine coolant to the level below the thermostat.
(Refer to Cooling System - "Coolant")
Remove the vacuum pump.
(Refer to Cylinder Head Assembly - "Camshaft")
Disconnect the radiator upper hose (A).
Remove the thermostat cover (A) and thermostat (B).
Tightening torque :
24.5 ~ 34.3 N.m (2.0 ~ 2.5 kgf.m, 18.1 ~ 25.3 Ib-ft)
Remove the battery and battery tray.
(Refer to Engine Electrical System - "Battery")
Disconnect the EGR cooler.
(Refer to Intake and Exhaust System - "EGR Cooler")
Remove the thermostat housing (A) with the gasket.
Tightening torque :
9.8 ~ 11.8 N.m (1.0 ~ 1.2 kgf.m, 7.2 ~ 8.7 Ib-ft)
When installing the thermostat housing, replace the gasket with a new one.
Install in the reverse order of removal.
Fill with engine coolant.
(Refer to Cooling System - "Coolant").
Start the engine and check for leakage.
Immerse the thermostat in water and gradually heat the water.
Check the valve opening temperature.
Valve opening temperature: 90±1.5°C(194±34.7°F)
Full opening temperature: 100°C (212°F)
If the valve opening temperature is not as specified, replace the thermostat.
Check the valve lift.
Valve lift : 8mm (0.3in) or more at 100°C (212°F)
If the valve lift is not as specified, replace the thermostat.
