Electric Fan Conversion (Ford Ranger)

[allc0re]

This is my first "real" thread, FYI.

I did some searching and couldn't find the answers I was looking for re electric fan conversions.

I have a Ford Ranger 2.5L 4 Cylinder 5-speed. I want to convert the belt fan to an electric one. I have an old fan from a V8 Thunderbird which should be more than sufficient. My first question is: how do I figure out at which temperature the fan should switch on and off? I was looking at thermostat relay kits and there are a few different temperature ranges that are available. Also, do I need an AC override, or is that not necessary?

[almightybmw]

have you checked out the ranger station? Best forum for the ranger. I'm sure there's a thread on there about e-fan conversions. I know for my Sonoma there a few kits with sensors I install to mimic the always spinning fan. I know I can get the kit at checkers for $80 or so, check out auto part stores as well.

[Allch Chcar]

Rangerpowersports has a guide on electric fan conversions. A/C bypass is necessary if you have A/C. For the temperature, you'll want whatever your Thermostat is, stock is 195 degrees.

The electric conversion kits are NOT cost effective. If you can do it yourself with a pulled part you'll see a benefit, otherwise it's just for show.

[brucepick]

I did an e-fan conversion on my rwd Volvo 240 with 2.3 liter engine. It seemed to help FE.

Toughest part was managing the fan switching. I too wanted to mimick the constant breeze of the belt fan without excessive operation of the e-fan. I ended up very happy with a relay link running off the brake light circuit. When not moving or when crawling in traffic, the fan runs on low speed.

I added a temp switch in the rad lower hose (return hose) which is set some 20 deg. F cooler than the engine thermostat. So if the water from radiator isn't sufficiently cool to support the engine, the fan comes on, high speed. I got the temp for that switch set nicely; it comes on for long highway upgrades in summer, or if I idle it without using the brake. Otherwise it rarely activates.

Why I didn't use an upper (hot) hose switch -
I tried various temp switches in the upper (hot) radiator hose before going to the lower hose solution. In the upper hose, all switches would come on at highway speeds because the water there was already hotter than it should be (because it needs cooling). When I tried an upper hose switch at a high enough temp so it wouldn't come on from normal highway cruising, it also didn't help much in idling situations (stayed off too long), due to being set for too high a temp. Eventually of course it would come on but the temp gauge was rising by that point - which is what I didn't want happening.

[allc0re]

Originally Posted by Allch Chcar

Rangerpowersports has a guide on electric fan conversions. A/C bypass is necessary if you have A/C. For the temperature, you'll want whatever your Thermostat is, stock is 195 degrees.

The electric conversion kits are NOT cost effective. If you can do it yourself with a pulled part you'll see a benefit, otherwise it's just for show.

Thanks for the info. I'll check Rangerpowersports.
I bought the relay kit for $35 and the fan came from a yard at $35 also(if I remember correctly), so altogether that's only $70 bucks in this. I should recoup the money in about 2 years of driving if gas stays at $2/gallon.
I'll try to take some pics of my progress and final setup.

[allc0re]

So this afternoon I removed the belt fan and mounted the electric fan. It turned out that turning the electric fan shroud (from a '96 T-Bird) 90 degrees from the way it was intended to be mounted was almost a perfect fit in my Ranger. I drilled 3 holes in the plastic shroud and used 1 original hole to mount it to the radiator. All mounting hardware was salvaged from around the garage (including leftover bolts from a toilet mount kit ). Tomorrow (if I can find a place open) I'm going to get the needed wire splices and hookup the relay kit. I'm will use the red wire from what I assume is the wiper motor for the 12V switched source (see photo).

I do have some questions about the fan wires. There are four. One blue, one black, and two black with red stripes. The fan runs fine when hooking up blue to positive and black to negative. Do I need to worry about the other two wires? What could they be for? Some kind of speed control?

Just wanted to update the progress. Any tips and info would be appreciated.

[metroschultz]

Yes.
The extra wires are for a pwm speed control unit on the donor car.
The black is ground.
The black/red should be for high speed direct and the blue was for modulated speed.
I would hook the back to a good ground and then hit each of the other wires with
bat + to see how the fan reacts.
Also you want to make sure it is spinning in the correct direction.
A DC fan will spin both ways and pull/push more air in one direction that the other.
You can then take a front mounted fan and put it on the rear but it will not be as effective.
You may not need the ultra high speed direct drive from the original operation and use the slower speed to save energy and reduce the drag on the alt. Also save the fan a little by not asking it to always spin at max rpm.

[allc0re]

Thanks for the info, metroschultz. I finished the wiring tonight. I used the blue and black wires from the fan. When I tested it, it didn't matter which wire was connected to positive, it spun the same speed. Actually, with the relay kit between the fan and the battery, it seems to spin a bit slower than it did when directly connected to the battery. It still pulls a ton of air, so it should be fine.

After the install I found that there was not enough clearance between the fan motor and the water pump pulley as it would rub in certain situations. After modifying the fan shroud and remounting it higher on the radator, it seems to be alright. I can actually notice a slight difference at low RPMs and when starting from a stop. We'll see how it affects gas mileage, but I think this mod is a winner.