1998 Toyota Sienna Thermostat replacement

REMOVAL

HINT: Removal 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.

DRAIN ENGINE COOLANT
REMOVE AIR CLEANER CAP WITH AIR CLEANER HOSE
DISCONNECT ENGINE COOLANT TEMPERATURE (ECT) SWITCH CONNECTORS
DISCONNECT ENGINE WIRE PROTECTOR FROM WATER INLET AND RH CYLINDER HEAD

Remove the 2 nuts, and disconnect the engine wire protector from the water inlet and cylinder head.

DISCONNECT WATER INLET PIPE FROM WATER INLET AND LH CYLINDER HEAD

Remove the bolt, and disconnect the inlet pipe from the water inlet.
Remove the O-ring from the inlet pipe.
REMOVE WATER INLET AND THERMOSTAT

Remove the 3 nuts, water inlet and thermostat.
Remove the gasket from the thermostat.

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