Afternoon folks,
Need some help please with the fans on my 2WD Saph, basically they do not kick in as they obviously should do when the engine gets up to temperature.
I've pulled the fan switch and bridged across it and i can hear the relay clicking but it does not set the fans off.
The car has been stood for quite a while and a few years ago i changed the cooolant header tank for a 4 WD tank which has the flow & return pipes in a slightly different location on the tank to the original 2WD.
one.
I'm wondering if i've introduced a problem when I've changed the tank.
I deals what the issue is here and are there any other checks i can do?

Many thanks.

 

Not precisely sure what you mean regards the hose changes however it doesn’t sound like anything that would cause any issues, but the first test you’ve done by bridging the connector to the fan switch should have worked, however the fan circuit in these cars is notorious for going bad and melting relays and the fuse box, so if not done already I suggest you invest in a good quality fan loom from the likes of MSD or elsewhere. You should also be able to unplug the wiring at the fans themselves (if no one has messed with it) I’d try temporarily running a couple of wires directly from the battery to see if the fans work that way, if they do then get a new fan loom ordered.

 

Hello Rog,

For the header tank the old one had the feed from the turbo at the top of the tank so when it was running you could see the water flowing back in. The 4 WD version, the turbo pipe hose size is physically bigger, the stub end at the tank was larger so i had to buy a different pipe to fit, i think it was from MSD. Also the stub end on the tank is lower down so you cant see the water flowing as its below the MAX level mark.
I hope that makes sense.
So for the fans - The fusebox is in good condition and the fans spin freely by hand. I'll put a 12v feed to the and see what happens.
Thanks for the tip, ill try tomorrow.

 

Ah got you, no that won’t make any difference to it, all good.

Here’s an old thread on the fan wiring, basically it was shit when new so it’s probably the most likely cause of your issue. https://passionford.com/forum/ford-s...an-wiring.html

 

Thanks for the link, an interesting read.
I intend to fit new looms for both the fan and fuel pump but want to get it running as normal after brining it out of hibernation.
I started it today after fitting some new plugs and its running worse than it did with the old plugs!!
I've actually has the car for 29 years (its on 102K miles) and the fans have never been a problem up until now, anyway - 12v to the fans tomorrow and see what happens.

Cheers.

 

Ok , so i put a 12V feed direct to the fan switch and....nothing.
Anyone know which are the correct relay & fuse positions are in the fuse box please?
The fuse i first looked at was the one for the blower!

Thanks.

 

Success!
So i put 12v direct to the fans again today.. I connected up to the bullet connectors on the fan loom as opposed to the plug at the back of the radiator and the fans fired up.
I checked the relay in the fuse box, found which one it was by shorting across the fan switch, its in good condition, no signs of drawing to much current thankfully. The bullet connectors were a but crusty so i cleaned them up, Let the car run up to temp and the fans came on as the needle got past the O on NORM. I wonder if there was a voltage drop across the crusty bullet connectors.
Job done.
Still will fit a new fan loom as well though.

Thanks.

 

Glad you got it sussed. Applying voltage to the fan switch connector shouldn’t do anything, you just need to bridge those to pins together, that is what operates the relay definitely sounds like you had a bad connection somewhere though. When fitting the new fan loom it is advised by specialists to fit the relay part behind the battery so it doesn’t get wet, I made the mistake of putting them next to the ignition amplifier on the inner wing and my fans wouldn’t go off after washing the car.

 

Rog,

Thanks for that, i was actually intending to fit the new relay in that exact spot as there are some pre drilled holes already there.
Top tip, cheers.

 

Thats where I fixed mine, need to re think this then.