Electric fans?

[DocBar]

Electric fans not working is news to me. I know many people say it doesn't work, but it's been fine for me.. I've been daily driving some Flex-a-lite fans on my OBS for a few years now here in Texas without any issues. Towing (15k max gross for me), Austin rush hour traffic, no problems. Sure is nice to be able to do anything on the front of the engine without having to pull a fan shroud.

Anyways, we aren't here to argue that point. OP, go check out the junkyard. Find some fans from a small car. Lincoln Mark VIII's, Taurus, T-birds, etc. Fans from all of these cars will be fine for a pulling truck. You can wire them up on a switch or you can set them up on a temp probe, either way. I would just do a simple switch so that you can turn them off during the pull and then turn them on after you finish the pull. If you decide to use a temp probe, get a setup that puts the probe in the upper hose. I switched my Flex-a-lites on two of my trucks to this style and it's much better than a probe in the radiator fins.

I'm curious as to why you would want to turn the electric fans off at all while the truck was running? I would use the switch to kill the fans when I killed the truck unless not having an alternator is part of having a pulling truck.

 

[strokin'_tatsch]

I'm curious as to why you would want to turn the electric fans off at all while the truck was running? I would use the switch to kill the fans when I killed the truck unless not having an alternator is part of having a pulling truck.

It's going to sound crazy, but the more and more power the alternator has to produce to hold a certain voltage, it takes a little more power to turn it. IIRC it's only like 1 horsepower for every like 10-12 amps or something like that. So theoretically my Flex-a-lite fans need about an extra 3.5hp to turn when they are on high speed than if the fans were off. Not much, but I pull without the fans running if I can get away with it. That's not to say what I do is what everyone else should do. It's just what I do and I know a couple other guys that do it, so I figured I'd throw that option in there in case that's what someone else wants to do. We need all the help we can get afterall.. LOL If you hook to the sled with coolant already at 210*, sure you may want to keep the fans running. When I hooked last weekend, the coolant was around 185-190* IIRC. At the end of the pull I turned on the fans as I was pulling away from the sled and coolant was 215*.. That's not overheating by any means.. I've driven at that temp for hours on end before, I don't think that a few minutes at that temp will hurt it.

 

[ibestroken]

I actually did get some mounted. I used a dual fan set up out of a 3.8 windstar. I will try and get some pictures up of them. Wiring needs to be cleaned up some but was in a rush to get them mounted the morning of a pull. Will try and take some pics tomorrow

 

[PsdPullerJr]

I've hooked with water temp at 180*, looked at temp gauge as soon as stop and it was over 240*. This was with the factory fan and it started dropping just like egts do. I put a 16" flex a lite 2500 cfm fan in mine last weekend and I think it will work fine but I think I will try to add another.

 

[DocBar]

It's going to sound crazy, but the more and more power the alternator has to produce to hold a certain voltage, it takes a little more power to turn it. IIRC it's only like 1 horsepower for every like 10-12 amps or something like that. So theoretically my Flex-a-lite fans need about an extra 3.5hp to turn when they are on high speed than if the fans were off. Not much, but I pull without the fans running if I can get away with it. That's not to say what I do is what everyone else should do. It's just what I do and I know a couple other guys that do it, so I figured I'd throw that option in there in case that's what someone else wants to do. We need all the help we can get afterall.. LOL If you hook to the sled with coolant already at 210*, sure you may want to keep the fans running. When I hooked last weekend, the coolant was around 185-190* IIRC. At the end of the pull I turned on the fans as I was pulling away from the sled and coolant was 215*.. That's not overheating by any means.. I've driven at that temp for hours on end before, I don't think that a few minutes at that temp will hurt it.

Is that amperage even close to the HP draw of the factory fan? I doubt it. Even if it is, it doesn't affect the horsepower like a conventional fan does. You're merely looking at battery life. That could impact you on a pull, but I doubt it,