Thread: Wiring an Electric Fan

depends how you want to wire it, and what you want it to do, do you want an indicating light?

do you want the indicator light to indicate on the switch or the power to the fan?

do you want it setup so that it comes on with the accessories, only when the ignition is on, the alternator is making charge, or do you want to be able to turn it on regardless of key position?

do you want to put a thermo switch on it so that it will also only turn on if the engine is above a certain temperature?

do you want it to latch on so you can just hit a push button and then it will stay on till the ignition/accessories re turned off?

lots of options, and most of it can be done with just a few simple bits but they ll have very subtle differnt wire up options

Do you mind if I ask why? Makes much more sense to have wired to a temp control unit, standard Davies Craig unit. You could also put in an override switch.
I fitted 2 thermos to my Defender, 1 that come on with the air con, just tapped into the air con line and the other via temp controller.
I did draw up a basic electrical diagram as to how mine is wired. If I remember I will get it tonight and post. If I don't remind me. Would be pretty simple to add a manual override switch.

Definitely wire it up to a temp sender/controller. Only reason you would want an isolator is for water crossings, otherwise if you have it manually controlled you might forget to turn it on...

Is that the alisport radiator and fan?

Where would I put the temp switch in? Would I need to drill and tap something myself? It seems like this would be the best option, but I just thought it would be too hard.

I don't particularly need the manual switch, I was just going to use it as I thought it would be easier.

And yeah it is an allisport radiator and fan.

Doesn't the radiator come with a temp sender? Or is that already hooked into the factory gauge?

There was a american site I had come across that sold home made controllers, can't recall what they were caled though. Those Davies Craig ones might be better value.

Use a Davies Craig thermo switch as mentioned above. They come with wiring diagram and everything you need to set it up, minus a relay, fuse and the switch you want in the cab. Very simple set up.

I run mine (1985 110 V8) off this set up, but I decided to wire it to the battery (via a fuse box) instead of switched via ignition because I like the idea of it running on after the ignition is switched off, to remove heat from the engine bay etc until coolant temp drops and it switches itself off.

Originally Posted by Devans

Where would I put the temp switch in? Would I need to drill and tap something myself? It seems like this would be the best option, but I just thought it would be too hard.

I don't particularly need the manual switch, I was just going to use it as I thought it would be easier.

And yeah it is an allisport radiator and fan.

Look on Ebay,you can get fittings already threaded for the switch that go in you rad hose. Pat

Hi Devans,
I have attached a basic diagram of my layout. You could also put a switch in on the ignition line or similar. I have also included a diagram of how my light upgrade is wired in. I put the relays for the fans under the drivers seat in the box. The light relays are under the inspection plate on the front drivers side guard in the engine bay, I bought 2 x fans and 1 by thermo controller knob by Davies Craig came with relays etc.
Cheers
Craig