Toyota 1HZ Repair Manual

CO-10
COOLING SYSTEM - Thermostat
THERMOSTAT
REMOVAL OF THERMOSTAT
1. DRAIN ENGINE COOLANT (See page CO-5)
2. REMOVE WATER INLET
Remove the three bolts and water inlet from the water inlet
housing.
3. REMOVE THERMOSTAT
INSPECTION OF THERMOSTAT
INSPECT THERMOSTAT
HINT: The thermostat is numbered with the valve open-
ing temperature.
(a) Immerse the thermostat in water and gradually heat
the water.
(b) Check the valve opening temperature.
Valve opening temperature: 74-78X (165-172°F)
If the valve opening temperature is not as specified, replace
the thermostat.
(c) Check the valve lift.
Valve lift: 10 mm (0.39 in.) or more at 90°C (194°F)
If the valve lift is not as specified, replace the thermostat.
(d) Check that the valve spring is tight when the thermo-
stat is fully closed.
If necessary, replace the thermostat.
CO0948
C00941
CO0929
Valve Lift
CO0949

Toyota 1HZ Specifications

General

Fuel Type	Diesel
Maximum Power	96 kW (129 hp) at 3800 rpm
Firing Order	1-5-3-6-2-4
Aspiration	Naturally aspirated
Fuel System	Direct injection
Cooling System	Water-cooled
Displacement	4.2 L (4164 cc)
Maximum Torque	285 N·m (210 lb·ft) at 2200 rpm
Valvetrain	SOHC, 12 valves (2 per cylinder)