I am getting ready to install an electric fan in my rig. The wiring harness and relays are set to turn the fans on at 185 degrees and off at 170 degrees. Can anybody tell me what temperature thermostat I will need to optimize this system?

Thanks for the help

 

Where is the temp sensor for the fan going to be mounted? Is it measuring coolant temperature in the engine, or in one of the radiator tanks?

If the temp sensor will be in the engine, those temperature seem too low. You could get away with them if you ran a 160 degree thermostat. If you ran a 180 degree thermostat, your fan would pretty much run all the time once it came on. With the stock 195 degree thermostat it the fan would run constantly.

 

I think the temperature sensor installs in the engine water jacket. I will not know for sure until I get the fan and wiring harness from the vendor

 

Don't go below a 180 degree thermostat. The engine needs to run at least that to cook the bad stuff out of the oil.

And I agree, you won't realize any benefits from the electric fan if you turn it on too early. Stock vehicles don't turn them on till around 230 degrees. You don't have to go that high, but I would run the stock thermostat(195degree) and make the fans turn on at 220.

 

Im planning to go with an electric fan in the next few months when I do an engine swap. I was considering one of these for the fan switch temp sensor:

Flex-a-lite 32084 - Flex-a-lite In-Line Radiator Hose Adapters - Overview - SummitRacing.com

Thought was to splice it into the radiator hose to measure the water temp as it was exiting the radiator.

 

I got my e-fans and thermostat controller kit in this week and answered my own question. The thermostat is designed to go in the water jacket on the engine. It is set to turn on at 185 degrees so a 180 degree thermostat would work the best so to give a 5 degree buffer for the thermostat to open before the fans cut on. I am fabricating a metal shroud to mount the two 12" fans on the radiator. I purchased a piece of sheet metal and using a metal break to form a lip and flange for mounting. I used hand shears to cut to size and to cut out for the fans. I will have pictures for you soon as I find time and learn how to put pictures on the forum.

 

Oh-FWIW, I found a cheap source of e-fans from GearHead Enterprises.