Thermostat - Toyota 4-Runner 1985 Repair Manual

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COOLING SYSTEM - Thermostat
THERMOSTAT
REMOVAL OF THERMOSTAT
1. DRAIN COOLANT
CO-5
Drain the coolant from the radiator into a clean container.
The coolant may be reused if specific gravity is within
specifications.
2. REMOVE WATER OUTLET
Remove the two bolts and water outlet from the intake
manifold.
3. REMOVE THERMOSTAT AND GASKET
INSPECTION OF THERMOSTAT
NOTE: The thermostat is marked with the valve opening
temperature.
(a) Immerse the thermostat in water and heat the water
gradually.
(b) Check the valve opening temperature and valve lift.
If the valve opening temperature and valve lift are out
of following specifications, replace the thermostat.
Valve opening temperature: 86 - 90°C (187 - 194
OF)
Valve lift: More than 8 mm (0.31 in.) at 100°C (212
OF)
(c) Check that the valve spring is tight when the ther-
mostat is fully closed, and replace if necessary.
INSTALLATION OF THERMOSTAT
1. PLACE THERMOSTAT IN INTAKE MANIFOLD
2. INSTALL WATER OUTLET
Install the water outlet on a new gasket with two bolts.
3. REFILL COOLANT
Close the radiator drain cock. Fill with a good brand of
ethylene-glycol coolant.