1998 Hyundai Lantra thermostat

Service and Repair

DISASSEMBLY AND INSPECTION

Drain the coolant down to thermostat level or below.
Remove the coolant outlet fitting and gasket.
Remove the thermostat.
Immerse thermostat in hot coolant to check proper valve opening temperature. Replace if necessary. Valve opening temperature: 82 °C (177 °F) Full opening temperature: 95 °C (205 °F) Valve lift (at full open): 8.5mm (0.33 inch) or more

REASSEMBLY

Check that the flange of the thermostat is correctly seated in the socket of the thermostat housing.
Install a new gasket and the coolant outlet fitting.
Refill the system with clean coolant.

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