How to Correctly Wire an Electric Fan?

[nando]

oh ok, i don't have A/C in mine, it's a M30 swapped one so it didn't fit. perhaps i could still connect to these wires and turn on the a/c whenever i need it. anyone have past experience with this way? or is this too beaner rigged?

as long as the wiring is there it's fine. You just need the lower temp thermoswitch. it will (should?) come on regardless of what the AC switch is doing.

[Holland]

To my knowledge using the stock thermoswitch it will come on automatically but very late. I need to get a lower one still but I just use the A/C switch to kick it on. I only rarely have to do this though because I'm moving most of the time and I live in AZ.

[mutty]

as long as the wiring is there it's fine. You just need the lower temp thermoswitch. it will (should?) come on regardless of what the AC switch is doing.

Where do I get the 80/88 switch?

[nando]

anywhere you get OEM parts, look up the part # on realoem.com or bmwfans.info, it should be under E36 318i cars.

[b*saint]

Best thing is to run a new independent circuit especially if the new fan draws more amperage. Plus I mean its only a fan and a temp switch. Just put the switch on the positive side lol.

[nando]

the stock fan draws a lot of power.. you'd need to go way overkill to draw more than it was meant to handle.

[Heysüß]

To my knowledge using the stock thermoswitch it will come on automatically but very late. I need to get a lower one still but I just use the A/C switch to kick it on. I only rarely have to do this though because I'm moving most of the time and I live in AZ.

yeah i haven't been in as much a hurry because it tends to stay very cool here as well since my city has few traffic lights and it's mainly mountain and country roads. so at cruising speed there's no real need for the fan.

the stock fan draws a lot of power.. you'd need to go way overkill to draw more than it was meant to handle.

this is what i've read as well.

[sonnyqm3]

I just bought a spal fan and a 318ti switch that has 3 pins. How do I wire it up.. thanks.

[ISB E30]

yeah i haven't been in as much a hurry because it tends to stay very cool here as well since my city has few traffic lights and it's mainly mountain and country roads. so at cruising speed there's no real need for the fan.

Hey man, I got mine in and running right, swing by or give me a call and we can get it straight.

[Charley]

How about this: My car never had A/C, what do I do?

I have a 16" spal(19amp I think) + a 80/88 switch +m42 rad that is getting swapped in.

I'd like it to turn on by itself when needed, I don't want to add a switch.

Charley

[bimm3r82]

So since everything is installed and i didnt take pics as i went thru the process Ill explain everything the best i can..
Products I bought:
E36 318 dual temp switch for radiator 80/88 61-31-8-361-787-M85
Thermostat for 6 cylinder car 80 degree 11-53-1-466-174-80
redline water wetter for the coolant
spal electric 16" low profile puller fan: bimmerworld
SPAL fan bracket and strap mouting kit: bimmerworld
SPAL fan relay and wiring kit (not the one with the temp unit)

Keep in mind i have no ac so this setup prolly wont work if you have ac since you are taking the aux fan wiring temp switch..

This first pic is the relay wiring kit. It has a 12v constant, 12v ignition, power to the fan, and signal from the switch..


I wired the 12v constant to the battery terminal you can see in the pic above, the ignition wire i wired directly to the fuse box to the rear defrost because mine doesnt work.. i ran the wire thru the rubber part on the side and sealed it up with liquid electrical tape where you can see below.. the power to the fan wire is simple it will have a plug that plugs to the fan and there will be a ground that you ground separately..


For the temp switch the best way i found is to connect the signal wire to the wire that plugs in with the temp you want the fan to kick on at.. I picked the lower temp, the higher one i just capped off, then the third wire which is the one closest to the front of the car i put just put to a ground source.. normally its a powered thru the ac.. you want it grounded.. Now it will simply kick on when you hit the temp in the switch and will never have to think about it.. I used the stock fan shroud and just cut out a bit where i mounted the brackets which are on each corner of the radiator.. you can see it at the top in one of the pics.. also you can see that there isnt much clearance for the fan, i bent the brackets up a little so it off the radiator but not much.. as it is right now it works perfect for me..

[nando]

why do you need a special relay.. there is already a high-current circuit and relay you can use that is wired to the thermoswitch.

Everyone *always* makes this so damn complicated. lol.

all you need to do is make sure the existing relays/fuses are working, swap the thermoswitch, and connect the power and ground to your new fan..

[bimm3r82]

why do you need a special relay.. there is already a high-current circuit and relay you can use that is wired to the thermoswitch.

Everyone *always* makes this so damn complicated. lol.

all you need to do is make sure the existing relays/fuses are working, swap the thermoswitch, and connect the power and ground to your new fan..

i tried that first actually.. wiring it through the ac system was more of a headache.. it either wouldnt work or just stay on all the time.. once i got that relay kit it was simple..

[nando]

it's not really the "A/C" system, although the A/C can turn it on, you don't need any of the A/C wiring for it to work. If it wasn't working right then something was shorted or a relay was bad.

[Jalves619]

I may be missing the point but the thermostat temperature is where your engine will be running at provided your cooling system is sufficient. By coupling an 80c thermostat with an 80c fan switch won't your fan will be running constantly at operating temperature? Correct me if I'm wrong, but it seems it would be better to separate the thermostat temp and the switch temp by a few degrees so that the fan turns on only when there is no airflow through the radiator.