eddie jr

I have an 85 2.8 FB and the rad fan is not working properly with the ac pressure switch. The fan works as required with the motor temp swtch but stays on all the time if you plug the ac pressure switch in. If i unplug the pressure switch harnes and put a paper clip in there the fan turns off as it should. I have now tried 2 brand new pressure switches and when i plug in the harness the fan still runs all the time, The sitches are aftermarket (four seasons and whatever the napa brand is) because GM does not make them anymore.

The switch seems to have continuity with the ac off (as it should) becuase the ac system is fully charged and otherwise working perfectly.

Any idea what is going on here? I don't like running the fan all the time as i am sure it will probably burn out the motor fighting the air when going down the highway, yet i will fry my ac compressor if i leave it grounded.

thanks.

eddie jr

anyone?

Apeiron

Why would it fight the air going down the highway?

eddie jr

Well, i just assumed that since the air rushing in at those speeds could act on the fan in a different way compared to the speed the motor is turning it and may stress it? Either way, it's not working right and i want to fix it! It shouldn't be running all the time.