Cooling System Flushing

All vehicles 

WARNING: Always allow the engine to cool before opening the cooling system. Do not unscrew the coolant pressure relief cap when the engine is operating or the cooling system is hot. The cooling system is under pressure; steam and hot liquid can come out forcefully when the cap is loosened slightly. Failure to follow these instructions may result in serious personal injury.
1. Drain the cooling system. For additional information, refer to Cooling System Draining, Filling and Bleeding .

Vehicles equipped with a 4.0L SOHC engine 

2. Remove the bolts, thermostat housing cover and thermostat. Install the thermostat housing cover and bolts without the thermostat.
   • Tighten to 10 Nm (89 lb-in).
Fig 1: Locating Thermostat Housing Cover Bolts
Courtesy of FORD MOTOR CO.

Vehicles equipped with a 4.6L (3V) engine 

3. Remove the throttle body (TB). For additional information, refer to FUEL CHARGING AND CONTROLS - 4.6L (3V) .
4. Disconnect the fuel vapor hose.
Fig 2: Locating Fuel Vapor Hose
Courtesy of FORD MOTOR CO.
5. Remove the bolts, thermostat housing cover and thermostat. Install the thermostat housing cover, the O-ring seal and the bolts without the thermostat.
   • Tighten to 10 Nm (89 lb-in).
Fig 3: Locating Thermostat Housing Cover Bolts
Courtesy of FORD MOTOR CO.

All vehicles 

6. Using a suitable cooling system flushing tool, flush the engine and radiator.
   • Use cooling system flush.

Vehicles equipped with a 4.0L SOHC engine 

NOTE: Prior to installing the thermostat, inspect the thermostat housing cover O-ring seal and install a new O-ring seal if necessary.
7. Install the thermostat, O-ring seal, thermostat housing cover and bolts.
   • Tighten to 10 Nm (89 lb-in).
Fig 4: Locating Thermostat Housing Cover Bolts
Courtesy of FORD MOTOR CO.

Vehicles equipped with a 4.6L (3V) engine 

NOTE: Prior to installing the thermostat, inspect the thermostat housing cover O-ring seal and install a new O-ring seal if necessary.
8. Install the thermostat, O-ring seal, thermostat housing cover and bolts.
   • Tighten to 10 Nm (89 lb-in).
Fig 5: Locating Thermostat Housing Cover Bolts
Courtesy of FORD MOTOR CO.
9. Connect the fuel vapor hose.
Fig 6: Locating Fuel Vapor Hose
Courtesy of FORD MOTOR CO.
10. Install the TB. For additional information, refer to FUEL CHARGING AND CONTROLS - 4.6L (3V) .

All vehicles 

11. Fill and bleed the cooling system. For additional information, refer to Cooling System Draining, Filling and Bleeding .