Cooling Fan

[Guest Jonnyround2003]

Do you have an oil cooler as I don't 2b

[Guest snowy2]

its extremely easy to make a circuit that will ensure that the fan ONLY comes on with the ignition switch.....without knowing how your car is wired, cut the fan wire (the +ve one) fit one to terminal 30 on a relay and fit the other to pin 87 (NOT 87a) from ANY ignition switched supply (coil?) take a connection to pin 85 on the relay pin 86 is connected to earth......

your fan will now ONLY work when the ignition is ON.

[Guest Jonnyround2003]

Thanks snowy 2

[Guest 2b cruising]

Yes, I have a small oil cooler.

That was my first thing done. Didn't work though.

[Guest Jonnyround2003]

2b can you send me some pics on what you have done to yours to jon@gasbits.com would be very much appreciated

[Guest 2b cruising]

Yes John I will do that tomorrow.

A little reminder just after mid day when I have some self time will be appreciated.

There is nothing but fresh air in my nose cone.

The overflow pipe goes into a spit and suck bottle but only spits if I've just over filled my radiator.

[Guest Jonnyround2003]

When the fan is spinning should you be able to feel air go through the rad at a stand still as I can't feel any ? Or does it only pull air through when moving along . My car was part built when I got her the other thing I've noticed is the fan thermostat has four wires from it but only two are connect the other two are just left cut off where should they go ?

[Guest Jonnyround2003]

When the fan is spinning should you be able to feel air go through the rad at a stand still as I can't feel any ? Or does it only pull air through when moving along . My car was part built when I got her the other thing I've noticed is the fan thermostat has four wires from it but only two are connect the other two are just left cut off where should they go ?

[fry61]

Sound like your fan MAY be going back-wards, is there a plug & socket somewhere near the fan -- see if it's reversible or try swapping the 2 fan wires over.

 

Best just check that neither wire is an earth/chassis wire on the fan side -- ( with both fan wires disconnected check that neither give a low ohms reading to earth/chassis.)

 

If the fan runs O.K in reverse check which side has blown air. Could also be the fan is mounted on wrong side of rad.

Edited July 8, 2016 by florin metal works

[Guest 2b cruising]

The switch wires go to the relay box first.

There shoul be two speeds on the fan so try coupling up the other two wires fist.

If your fan fits at the front of he rad you need a pusher fan, easily determined by the shape of the blades and the way it turns.

Back of the rad mounting means a puller unit.

The workin sides of decent blades are usually concave on the working side and angled with the leading edge towards the radiator no matter if it's pushing, pulling or DOR. Direction of rotation.

If it's the original fan it's a 4 fat bladed one and needs a two speed system.

Two speeds also means two relays.

Depending on your ecu type, when wired correctly they can be controlled by it.

If you wire direct, you must use a line fuse to protect it and the rest of your car.

I did an emergency fix on a Focus two weeks ago wiring through a switch and a relay. I fused this part of the circuit with a 5 nap fuse.

The feed wire to the high speed of the fan motor, I used a 40 amp fuse after experimenting.

Started at 10 and worked through adding a 5 amp increase each time. 30 just blew it so jumped up to a ford 40 boxed fuse.

Been ok since but the bloody woman will not take it and have it repaired properly.

I also completely bypassed the engine management so as not to cause any damage to that.

Sorry but I forgot about the photoes. Will do tomorrow. Don't forget to shout me if you haven't recieved by early evening.

No lights in the garage.

Edited July 8, 2016 by 2b cruising

[Guest snowy2]

if you use the ECU to control the fan you MUST use a diode protected (anti spike diode) relay or you run the very real risk of destroying the ecu when the fan shuts down due to the reverse EMF generated by the fan as it slows to a stop.

the green ford relay has this built in.....the connections are 30, 87, 85, 86 and 7....7 being the odd one out. this is connected to earth it provides a short to earth for the reverse EMF generated by the fan on shut down.

[Guest Jonnyround2003]

thanks 2 b I will send you pictures of how mine is set up my fan looks like an after market one about 400 mm in diameter with loads of thin blades about 30 mm wide the fan only has one speed not two only two wires come out of the fan . Starting to think my fan isn't doing its job I am sure its wired and mounted the correct way

[Guest 2b cruising]

It's still worth trying the other two wires as the voltage might be cut on one set to run the fan slower.

Just about sorted now so will send photo's shortly.

[Guest Jonnyround2003]

I've just checked my fan temperature stat and I'm getting ohms readings even when hot

[knights_templar]

You will get "continuity" when hot, the thermo switch is switched ON, unless I have misread the above your problem is that the fan remains on, so either the thermo switch is switching on too low or the engine is running at a higher temp than the switch. what does your gauge indicate when the fan starts up?

 

You mention the VG loom, which, from my info, did not have a fan circuit, it was designed for an engine driven fan, so any circuit you have is separate to the loom, and from your description is live fed through a thermo switch OR through a relay controlled by a thermo switch, to the fan and then to ground.

 

Have you any pictures ?