Overheating while driving on the highway with A/C on?

HUDSONJ

MEMBER
1993 FORD E-SERIES VAN
5.8L
V8
2WD
AUTOMATIC
1,504,748 MILES

Our van, 1993 Ford E-150 Econoline, is only overheating on the highway when the air conditioner is going. If the heater is on it does fine. Thermostat has checked out fine. We flushed the radiator; spark plugs have been replaced along with some hoses. Could the air conditioner be bad? It doesn’t seem to turn off at all (constantly running when on).

1 Reply

KEN L

MASTER CERTIFIED MECHANIC
48,420 POSTS

When the engine is overheating can you hear the fan clutch engaged? If not, this is your problem, here is a guide that can help as well, and I have included how to change the fan clutch out in the diagrams below:

https://www.2carpros.com/articles/engine-overheating-or-running-hot

and

https://www.2carpros.com/articles/fan-clutch-removal

REMOVAL AND INSTALLATION
1. Remove fan clutch from water pump pulley by removing the four bolts holding the fan blade and fan clutch assembly to the water pump.
2. Remove fan shroud retaining screws.
3. Remove fan blade, fan clutch and shroud.
4. If fan blade and clutch must be separated, remove remaining bolts attaching fan blade to fan clutch.
5. Reverse procedure to install. Torque fan blade to fan clutch attaching bolts to 12-18 ft lb.

Make sure to use a high-quality replacement part. Check out the diagrams (below). Please let us know what happens.

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