Thermostat: Service and Repair

Engine Coolant Thermostat Replacement (LY7, LLT)

Removal Procedure

1. Partially drain the cooling system. Refer to Cooling System Draining and Filling (GE 47716) (Service and Repair)Cooling System Draining and Filling (Static Fill) (Service and Repair) .
2. Remove the upper intake manifold. Refer to Upper Intake Manifold Replacement (LP1, LY7) (Service and Repair) .
3. Disconnect the surge tank outlet pipe from the thermostat. Refer to Radiator Surge Tank Outlet Hose/Pipe Replacement (LLT) (Service and Repair)Radiator Surge Tank Outlet Hose/Pipe Replacement (LY7/LLT) (Service and Repair) .




4. Remove the coolant pipe/thermostat housing bolt (2).
5. Remove the coolant pipe upper bolt (7).
6. Remove the coolant inlet pipe (4) from the thermostat.




7. Remove the thermostat bolts (1).
8. Remove the thermostat (2) and discard the thermostat seal (3).



Installation Procedure





1. Install the thermostat (2) with a NEW thermostat seal (3).

Notice: Refer to Fastener Notice (Fastener Notice) .

2. Install the thermostat bolts (1).

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





3. Install the coolant pipe (4), NEW seal, and fasteners (2 and 7). Refer to Engine Coolant Inlet Pipe Replacement (Service and Repair) .
4. Connect the surge tank outlet pipe to the thermostat. Refer to Radiator Surge Tank Outlet Hose/Pipe Replacement (LLT) (Service and Repair)Radiator Surge Tank Outlet Hose/Pipe Replacement (LY7/LLT) (Service and Repair) .
5. Install the upper intake manifold. Refer to Upper Intake Manifold Replacement (LP1, LY7) (Service and Repair) .
6. Fill the cooling system. Refer to Cooling System Draining and Filling (GE 47716) (Service and Repair)Cooling System Draining and Filling (Static Fill) (Service and Repair) .