Show me your manual electric cooling fan setup

[LtFuzz]

Hey guys, I'd love some feedback on how you have your manual on/off cooling fans set up.

Space is a premium for me so I'm thinking of going with this setup:

15.5x26.25x2 5/8"

I should be able to squeeze that in. It's a puller setup and pulls 2500cfm while drawing 14-22 amps. It'll cover my radiator completely, length-wise, and leave an inch uncovered on the top and bottom.

I'm debating whether or not to spend the extra $50 to get the kit that comes with the variable speed/thermostat control. I like the idea of a fan that works automatically depending on cooling demand, but at the same time that also adds another layer of system complexity.

The other option is to get a basic wiring harness hooked up to a basic on/off switch. And I'd simply flip it on and off as needed. Keeping an eye on the temp gauge isn't really that hard and I do it regardless.

There's also this option:

Which lets you set the temperature target you want to hit before the fans come on. Seems like a decent compromise but again, an extra layer of complexity. If the sensor fails you're SOL. I suppose you could add another backup system... but I'm trying to keep this as basic as possible.

What're you guys running? Did you find a nice way to wire it up?

Thanks for the feedback

 

[ExpoScout]

At the moment I am using the stock clutch fan on my D1. However, I have used these setups before on other vehicles Ive built and IMO it's worth it to wire it in with the sensor so it comes on automatically.

I am also planning an E-fan setup currently, and I will have it wired to a coolant temp sensor so it comes on automatically.

Unless they are going to be used as secondary only fans, I wouldn't want to have to remember or think about turning them on/off constantly.

 

[LtFuzz]

At the moment I am using the stock clutch fan on my D1. However, I have used these setups before on other vehicles Ive built and IMO it's worth it to wire it in with the sensor so it comes on automatically.

I am also planning an E-fan setup currently, and I will have it wired to a coolant temp sensor so it comes on automatically.

My concern is what happens if/when the sensor fails?

Do you run a secondary system hard-wired to an on/off switch?

 

[ExpoScout]

You also have to remember that there are plenty of OE applications that use electric fans as primary with simple temp switches for actuators. I wouldn't have any problem using this setup, heck I've been relying on a clutch fan that may or may not work! lol

 

[ExpoScout]

My concern is what happens if/when the sensor fails?

Do you run a secondary system hard-wired to an on/off switch?

How often do you hear of temp switches failing? I've replaced the ones on both my rovers, and they were still working after 16 years and 120k+ miles. But I wouldn't call it a bad idea to have an override switch so you could turn it off or on manually. IF the sensor failed you could still turn it on and you could cut it off on water crossings.

 

[lwg]

I used to run a similar setup on my old RRC Buggy. I opted for the variable speed controller after the initial "cheap" controller failed. The variable speed is very nice with dual fans as they are much less noisy due to not running full speed all the time. Additionally be sure to mount the controller as far away from any heat source as possible. They like to fail. One other more failsafe option is to plumb an inline controller within the coolant hose, we did this for a Diesel conversion with electrics recently and it has worked well for us.

Also I personally would always recommend against using just a manual switch for fans. At some point something will distract you from watching that temp gauge and you'll overheat. I guarantee you. Plus if someone else ever drives your truck it has become much more difficult for them to operate, although this could be considered a plus in some cases!

 

[overlanddisco]

Good Fan!

Here's what I'm using- from Jeg's catalog. I wanted to be able to move the most amount of air- 4600 CFM- to keep the aluminum V8 alive. I've used this for 4 years now in central and northern AZ, lots of slow moving backcountry exploration with no issues whatsoever. When summer arrives, I adjust the fan control to come on earlier, so that the temp out of the thermostat is 200-205 degrees F with the fan on, and 215 with it off. I back it down a bit in the winter. The control is solid state circuitry, so very little can go wrong.

 

[LtFuzz]

How often do you hear of temp switches failing?

You're talking to a guy that managed to send his fan blade through his radiator :sombrero:

 

[LtFuzz]

Here's what I'm using- from Jeg's catalog. I wanted to be able to move the most amount of air- 4600 CFM- to keep the aluminum V8 alive. I've used this for 4 years now in central and northern AZ, lots of slow moving backcountry exploration with no issues whatsoever. When summer arrives, I adjust the fan control to come on earlier, so that the temp out of the thermostat is 200-205 degrees F with the fan on, and 215 with it off. I back it down a bit in the winter. The control is solid state circuitry, so very little can go wrong.

Yeah, I wish I could fit that bad boy... I'm limited to 2.75" of space between the block and the radiator.

 

[LtFuzz]

. One other more failsafe option is to plumb an inline controller within the coolant hose, we did this for a Diesel conversion with electrics recently and it has worked well for us.

Interesting -- how did you do this? Did you fish it through the original coolant temp sensor port and stack the temp sensor in front/behind it?

Or did you cut a hole into the hose and reseal? Wouldn't there be issues with expansion/contraction of the hose?

 

[r_w]

I had one of the motors burn up and knock out the second, so make sure both are independently fused and switched. I thought mine were but the second relay pulled latch power from the first. DOH.

 

[Rocket Ship]

How often do you hear of temp switches failing? I've replaced the ones on both my rovers, and they were still working after 16 years and 120k+ miles. But I wouldn't call it a bad idea to have an override switch so you could turn it off or on manually. IF the sensor failed you could still turn it on and you could cut it off on water crossings.

I've had one fail on another car. Car overheated, but luckily the engine isn't a POS like the Rover V8 so it was fine.

Have you considered a Taurus fan? They are the hot (erm... cool?) setup. Cheap, move a lot of CFM, and more reliable than the Flexalite. I have a Flexalite on one of my vehicles, but if I had to do it again, I'd choose an OEM unit.

 

[LtFuzz]

I've had one fail on another car. Car overheated, but luckily the engine isn't a POS like the Rover V8 so it was fine.

Have you considered a Taurus fan? They are the hot (erm... cool?) setup. Cheap, move a lot of CFM, and more reliable than the Flexalite. I have a Flexalite on one of my vehicles, but if I had to do it again, I'd choose an OEM unit.

Yeah the Jeep guys like them too.

It's about 1.75" too thick for my application though.

I'm struggling to fit a 2 5/8" fan set up

 

[ExpoScout]

I've had one fail on another car. Car overheated, but luckily the engine isn't a POS like the Rover V8 so it was fine.

Don't get me wrong, it happens, but it's probably less likely than forgetting to flip a manual switch if you are in the middle of a sketchy trail or something.

Like I said before, it doesn't seem like a bad idea to have a manual switch to override the sensor switch if it were to fail or in the event of a water crossing or some other situation where the fan needs to be manually controlled.

 

[Rocket Ship]

I agree completely. A manual only fan setup would be silliness. Having an Off/Auto/On switch would be the best setup.