i just put an electric fan on my 66 mustang and i am having problems. when the car is running, the switch will turn the fan on and off, as it should, but when i shut the car off, the fan wont stop running, i have exchanged the switch for a new one, and that is not the problem, and i am not sure what to do now? i have heard of putting a toggle switch for the fan? but i really dont want to have a switch in the car? any ideas? could it be a bad ground? when i checked everything looked fine? please advise? thanks

 

You need constant power going to your fan and switch, sounds like it's tied into your ignition atm.

 

Is it wired in like this?

 

This is why I don't run eletric fans in old cars. Flex-a-Lite SS 10,000 rpm works just fine. And it's a street car so you will never see the power drop. Fact-or-the-matter is most electric fans on new cars are for EPA and the tight temps required to meet it. I'm speaking of RWD cars of course.

 

Hmmm... That might be normal for your fan. My electric fan stays on after the engine is turned off, but the fan does go off when the radiator cools down. The longest the fan stays on is about a minute in my case...and that's on a very hot day. My previous electric fan was wired into the ignition system and did turn off with the engine. I believe it has to do with the switch and amount of control wires coming out of it. I don't know if you can use the ignition-shut-off-type switch in place of the thermostatic-shut-off-type. I never tried it because I don't mind the fan staying on.

 

I had an electric fan on mine whenI bought it.It will run until the temp sensor that you put in the fins of theradiator reads cool enough.The hotter it is outside and the hotter the car is ,the longer it will run after you shut the car off.
I didnt like it so when I replaced the motor I put a flexolite fan like mike is talking about on the car.
Jeff

 

If you don't want the fan to stay on after you shut of the car then wire it up to a switched output, like the radio output. Just keep in mind that you need to usea circuit like the one JamesW gave you but substitute the on/off/on switch with the "switched" output...

 

I think I misread you original post. Does it stay on indefinately or just up to a few minutes?

 

There is no toggle switch, If it is hooked up right, it will shut off after the rad temp comes back down. Yeah, you will hear the fan running after the engine is shut off, that's how electric fans work.

 

The toggle switch is only there for manual override.