Diesel Data: Automotive Repair

Thermostat: Service and Repair



Engine Coolant Thermostat Replacement (LZ4)

Removal Procedure





1. Drain the cooling system. Refer to Cooling System Draining and Filling (L61) (Service and Repair) .
2. Remove the air cleaner outlet duct. Refer to Air Cleaner Outlet Resonator Replacement .
3. Reposition the radiator outlet hose clamp at the thermostat housing.
4. Remove the radiator outlet hose from the thermostat housing.




5. Remove the thermostat housing bolt/stud.
6. Remove the thermostat housing and gasket.
7. Remove the thermostat.
8. Clean the gasket surfaces.



Installation Procedure





1. Install a NEW thermostat.
2. Position a NEW gasket and the thermostat housing to the engine block.

Notice: Refer to Fastener Notice (Fastener Notice) .

3. Install the thermostat housing bolt/stud.

Tighten the bolt/stud to 25 N.m (18 lb ft).





4. Install the radiator outlet hose to the thermostat housing.
5. Position the radiator outlet hose clamp at the thermostat housing.
6. Install the air cleaner outlet duct. Refer to Air Cleaner Outlet Resonator Replacement .
7. Fill the cooling system. Refer to Cooling System Draining and Filling (L61) (Service and Repair) .
8. Inspect the system for leaks.