NOTE: I've seen several people get flamed on other forums for using an electric fan. This is a TURBOCHARGED application, mechanical fan is not an option.

So I have the Flex-A-Lite 40 electric fan from Summit. I'm not wiring for A/C or a manual switch, but I am running for a constant run application where it stays on until it cools the engine compartment to the desired temperature (redneck turbo timer).

So three wires, easy enough right? Wrong. Where this gets interesting is the battery has been relocated to the toolbox in the bed, so I stuck both of the hot wires on the terminal where the positive cable from the battery goes into the fuse box and the ground cable is hooked to the ground strap coming off of the engine block. The temperature solenoid thingy was mounted in the radiator as close to the upper hose as possible, per instructions. The motor was definitely warm (I decided to set my boost pressure solenoid, so I know hitting 12psi a couple times warmed that motor up pretty good). No fan. Turned the temperature dial all the way down. No fan.

What did I do wrong?

 

i have a flex 180 with the probe switch... what i learned was that your fan wont turn on unless your t-stat is letting the coolant run into the rad. when i start my truck up cold i watch the temp rise to 210 and the fan doesnt kick on, at 210 my tstat works and the coolant runs into the rad and my temp drops to 193 ish and the next time the temp runs back up the fan kicks on because there is hot coolant circulating... maybe put a 180 tstat in your truck if you didnt already so it pushes coolant into rad earlier. I thought the wiring was super straight forward and put my fan in about 3 hrs. my fan is wired into my radio wire so it turns off when my truck is turned off cuz my batt is old... but i had it hardwired for a while and it still worked great.

If i were you, find an accurate way to read your temp(down to the degrees from your engine sensor), i would start up your truck, let it idle until the temp gets up and the tstat works( might take 10-15 min), then a few minutes after that the temp should trigger the fan...

good luck man\

M