Thermostat Housing: Service and Repair

Engine Coolant Thermostat Housing Replacement (LNF)

Removal Procedure

Important: A drain has been provided at the bottom of the water pump for engine block coolant drainage.







1. Drain the cooling system. Refer to Cooling System Draining and Filling (GE-47716) (Service and Repair)Cooling System Draining and Filling (2.4L LE5 Only) Cooling System Draining and Filling (Static Fill-LNF) (Service and Repair) .

Notice: Refer to Fastener Notice (Fastener Notice) .

2. Drain the coolant from the engine block at the water pump drain. After the coolant has drained, tighten the drain bolt.

Tighten the drain plug to 20 N.m (15 lb ft).

3. Lower the vehicle.
4. Remove the air inlet grille panel. Refer to Air Inlet Grille Panel Replacement (SKY) (Service and Repair)Air Inlet Grille Panel Replacement (Solstice) (Service and Repair) .




5. Disconnect the engine wiring harness electrical connector (3) from the engine coolant temperature (ECT) sensor.




6. Remove the ECT sensor, if necessary.




7. Reposition the radiator outlet hose clamp (2) at the thermostat housing.
8. Remove the radiator outlet hose from the thermostat housing and reposition out of the way.
9. Remove the exhaust manifold. Refer to Muffler Replacement (LNF) (Service and Repair)Muffler Replacement (LE5).




10. Reposition the heater inlet and outlet hose clamps at the thermostat housing pipes.
11. Disconnect the heater inlet (2) and outlet (1) hoses from the thermostat housing pipes.




12. Remove the thermostat housing bolts.

Important: Twist the water transfer pipe while pulling in order to remove it from the water pump.


13. Remove the thermostat housing from the vehicle.
14. Remove the water transfer pipe from the thermostat housing, if necessary.
15. Remove and discard the water transfer pipe O-ring seals, if necessary.




16. Remove the thermostat housing cover bolts and cover, if necessary.
17. Remove the thermostat, if necessary.
18. Remove and discard the thermostat housing O-ring seal, if necessary.
19. Remove all debris and thread sealant from the engine coolant temperature sensor and bolt holes if the housing is being re-used.



Installation Procedure





1. Install a NEW thermostat housing cover O-ring seal into the recess groove.
2. Install the thermostat, if necessary.

Notice: Refer to Fastener Notice (Fastener Notice) .

3. Install the thermostat housing cover bolts, if necessary.

Tighten the bolts to 10 N.m (89 lb in).

4. Install a NEW thermostat housing to engine gasket onto the thermostat housing.
5. Load the thermostat housing assembly into position while the vehicle is lowered.
6. Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle (Service and Repair) .





Important: The water feed pipe seals can be lightly lubricated with coolant to aid during installation.


7. Install NEW O-ring seals onto the water feed pipe.

Important: Lubricate the O-rings with coolant ONLY.


8. Install the water feed pipe into the thermostat housing aligning locator tab.
9. Align the water pipe to water pump.
10. Seat the water feed O-ring seal by pushing inward toward the water pump. Take care not to tear or damage the O-ring.
11. Lower the vehicle.
12. Position the thermostat housing against the engine.
13. Install the thermostat housing bolts.

Tighten the bolts to 10 N.m (89 lb in).





14. Connect the heater inlet (2) and outlet (1) hoses to the thermostat housing pipes.
15. Position the heater inlet and outlet hose clamps at the thermostat housing pipes.
16. Install the exhaust manifold. Refer to Muffler Replacement (LNF) (Service and Repair)Muffler Replacement (LE5).




17. Install the radiator outlet hose to the thermostat housing.
18. Position the radiator outlet hose clamp (2) at the thermostat housing.




19. If reinstalling the old sensor, coat the threads with sealant. Refer to Sealers, Adhesives, and Lubricants (Specifications) .
20. Install the ECT sensor, if necessary.

Tighten the sensor to 20 N.m (15 lb ft).





21. Connect the engine wiring harness electrical connector (3) to the ECT sensor.
22. Install the air inlet grille panel. Refer to Air Inlet Grille Panel Replacement (SKY) (Service and Repair)Air Inlet Grille Panel Replacement (Solstice) (Service and Repair) .





Important: The vehicle must be level when filling the cooling system.


23. Verify the drain plugs at the radiator and water pump are tightened.
24. Fill the cooling system. Refer to Cooling System Draining and Filling (GE-47716) (Service and Repair)Cooling System Draining and Filling (2.4L LE5 Only) Cooling System Draining and Filling (Static Fill-LNF) (Service and Repair) .
25. Lower the vehicle.
26. Inspect for any leaks.