Thermostat: Service and Repair

Thermostat - 4.6L (3V)

Thermostat and Thermostat Housing - Exploded View 4.6L (3V) (Part 1):

Thermostat and Thermostat Housing - Exploded View 4.6L (3V) (Part 2):

Removal
1. Disconnect the battery ground cable. For additional information, refer to Battery.
2. Drain the engine cooling system. For additional information, refer to Cooling System Draining, Filling and Bleeding.
3. Remove the air cleaner outlet pipe. For additional information, refer to Fuel Delivery and Air Induction.
4. Remove the accessory drive belt. For additional information, refer to Drive Belts, Mounts, Brackets and Accessories.
5. Disconnect the crankcase vent tube from the intake manifold and position it aside.
6. Remove the 2 generator support bracket outer bolts.
7. Remove the 2 lower generator nuts and position aside the generator and wiring harness.

8. NOTE: RH thermostat cover bolt has a slotted flange.

Remove the LH thermostat cover bolt and loosen the RH bolt.
^ Position aside the thermostat cover and hose assembly.
9. Remove the thermostat O-ring seal and the thermostat.
^ Discard the thermostat O-ring seal.

Installation

1. NOTE: Lubricate the O-ring seal with clean engine coolant.

Install the thermostat with the smaller plate facing upward and a new O-ring seal.
2. Position the thermostat cover and install the 2 bolts.
^ Tighten to 10 Nm (89 lb-in).
3. Position the generator and wiring harness and install the 2 nuts.
^ Tighten to 25 Nm (18 lb-ft).
4. Install the 2 outer generator support bracket bolts.
^ Tighten to 10 Nm (89 lb-in).
5. Connect the crankcase vent tube to the intake manifold.
6. Install the accessory drive belt.
7. Install the air cleaner outlet pipe.
8. Connect the battery ground cable. For additional information, refer to Battery.
9. Fill and bleed the cooling system.