REMOVAL AND INSTALLATION
If the replacement thermostat is equipped with a &inch;jiggle pin&inch;, the pin must be install facing upwards toward the top of the engine (12 o'clock), and should be on the side facing the water outlet. When installing the thermostat gasket, the seal print side should face the cylinder head.2.2L Engine
See Figure 1
- Drain enough coolant to bring the coolant level down below the thermostat housing. the thermostat housing is located on the left front side of the cylinder block.
- Disconnect the temperature sending unit wire.
- Remove the coolant outlet elbow.
- If so equipped, position the vacuum control valve out of the way. The vacuum control valve is not used on California trucks.
- Disconnect the coolant by-pass hose from the thermostat housing.
- Remove the thermostat and housing from the engine.
- Note the position of the jiggle pin and remove the thermostat from the housing.
- Remove all gasket material from the parts.
- Position the thermostat in the housing with the jiggle pin up. Coat a new gasket with sealer and install it on the thermostat housing.
- Install the thermostat housing using a new gasket with water resistant sealer. Tighten the bolts to 14-19 ft. lbs. (19-25 Nm).
- Install the coolant outlet elbow and vacuum control valve (if equipped).
- Connect the by-pass and radiator hoses.
- Connect the temperature sending unit wire.
- Fill the cooling system with the proper coolant. Operate the engine and check the coolant lever. Check for leaks.
2.6L Engine (1987-88)
The thermostat is located in a water box at the timing belt end of the intake manifold.
- Drain the cooling system to a level below the thermostat.
- Remove the hoses from the thermostat housing.
- Remove the thermostat housing.
- Remove the thermostat and discard the gasket. Clean the gasket surfaces thoroughly.
- Position the gasket on the water box. Center the thermostat in the water box and attached housing. Tighten the bolts to 15 ft. lbs. (20 Nm).
- Connect the radiator hose to the thermostat housing. Tighten the hose clamp to 35 inch lbs. (4 Nm).
- Fill the cooling system.
2.6L Engine (1989-93)
The thermostat housing is at the end of the upper hose, on the cylinder head side, above the alternator.
- Drain the cooling system to a point below the housing.
- Remove the upper hose.
- Remove the upper nut and lower bolt and remove the housing.
- Remove the gasket and thermostat. Discard the gasket.
- Thoroughly clean the mating surfaces of the head and housing.
- Position the new thermostat in the head with the jiggle pin on the upper side.
- Coat the gasket with an adhesive sealer and stick it in place on the head.
- Install the housing and tighten the nut and bolt to 19 ft. lbs. (26 Nm).
- Fill the cooling system.
See Figures 2 through 6
The thermostat housing is located at the engine end of the lower radiator hose.
- Raise and support the front end on jackstands.
- Drain the cooling system.
- Remove the lower hose.
- Unbolt and remove the housing and thermostat.
Some engines have a housing which incorporates an O-ring, eliminating the need for a gasket. On these engines, use no sealer when replacing the housing.On engines which incorporate a gasket, thoroughly clean the mating surfaces and use a new gasket coated with adhesive sealer.