How do you replace the thermostat located on a Ford E-350?

Answer 1

On my E350 motorhome, I had to remove the large black plastic air cleaner to see the thermostat housing.

[The left side comes out with no tools; unclip the band, pull out.

[Just 4 bolts and one clamp to remove the right side; not completely necessary but it sure makes the job easier.

I drained 4 liters of coolant. There is a place to attach a hose on the bottom of the radiator and a plastic bolt to let the coolant flow into the hose. Easy to run the other end of the hose into a jug. But 4 liters wasn't enough; it began to flow out of the thermostat housing when I loosened it. 6 liters was about right.

Follow the large hose that comes from the top of the radiator to the top of the motor. This is the housing that holds the thermostat. Two bolts to remove.

The thermostat came out easily. Carefully note the location of the rubber o ring on your unit; mine was on top of the thermostat.

Get a new thermostat from your auto supply store. You'll need the model, year and engine size. A good idea to get a new o ring, though it will double the cost. My cost was $15.

Easy to put it in and reassemble. Wet the o ring with coolant. Tighten the two bolts so they are about as tight as before. Better a little loose than broken! Don't forget to put the coolant back in. It should be colored and not look dirty; if not you should flush and put new coolant in.