electric cooling fan
- Thread starter chilwil86
- Start date
bobby6319
Member
you can buy a fan wiring kit from jegs with the temp sender relay and wiring for abot 30 bucks. you will have to have a relay or it will feed back to the ignition and it will not die untill the fan stops spinning
The only thing that should be on the ign post of the switch is the hot wire going to the ignition. If you put the other stuff on the accessory side of the switch it won't run on. Same with a 3 wire alternator.
rooster57
Member
This is how i did it and it works great. I made a small bracket and mounted a 30 amp relay and a 30 amp breaker on a bracket low on the fan mounting bracket. Then i added a wire from the alt power post and fed the relay contact.Then from the other contact i fed the fan. Then ground the fan. MAKE A JUMPER FROM THE 12 VOLT FEED ON THE RELAY TO THE RELAY COIL. Now install a water-temp switch in the block. the temp switch goes to the common of the coil of the relay. So when the temp comes up the temp switch closes supplies a ground for the relay and the relay closes and the fan comes on. And the best thing is NO wiring in the car it all comes from the alt.
2old2fast
Active Member
Rooster, just to be clear, that means your fan is always hot, if you shut off the engine, the fan runs till the thermo switch shuts it off , or if that switch fails closed , the fan will continue to run , right? I think I'd rather have all elec dead when you turn off the ign. I.M.O. dave
rooster57
Member
No i have a master solenoid that shuts all battery voltage off when the key is off. Besides new cars fan runs beyond the ignition. If you purchase a good quality relay sized properly it will out last the fan. I think the benefit of no wiring inside the car body,no voltage drop, no high amperage circuit under the seat or carpet is a big plus. So feeding directly from the alt out weighs the possibility of the relay staying closed. respectfully dave my chicken brain opinion . Ha Ha
Cool32
Member
I like rooster's idea,good thinking keeping everything in the engine area. Also, the idea for the fan to keep running after turning off the ignition is so the engine continues to cool until the temp drops to the required level. Nothing worse than turning off and coming back 15 mins later and the engine is still cooking!!!!
Please do post pics,This always helps everybody.Lets see your set-up Rooster...Thanx for all the info guys..
The problem with electric fans is all the unsightly big wiring and relay. If you can hide that stuff it looks just OK IMHO, to me nothing like seeing a mechanical fan going round and round from the driver's seat. My .02 only. On the other hand, you just can't beat the cooling effectiveness of a properly installed electric fan.
benT
Active Member
I agree with you Steve that the electric fan is not the most traditional look, but I will add that in an open hooded hot rod, it is safer than a mechanical fan if you are not running a shroud. I run an electric on mine because I want to keep it compact and clean. I do like that when I'm tuning on it while running, I'm don't have to worry about the fan taking my hand off (I am aware of the fan belt though). If you do run a mechanical fan, please build a shroud to protect yourself and help your airflow. I dont; think there is a right or wrong, just a preference!
Francis Blake
Active Member
This aint no second info, I worked with a fellow that did a lot of car work and was off work for a while and when he came back he had the scars to show where he had been hit with a blade that came off of a mech fan (that's all we had then) he lost an eye and was hurting for a long time.
benT
Active Member
My setup is similar to Roosters. The wiring disappears under the frame rail where I have the relay installed. The fan is fitted to the shroud (by the rad fabricator). Here are a few pics (still in mockup) prior to the rad to firewall supports. I have about 1/4" clearance from the snout of the fan motor to the pulley bolt!
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