Originally Posted by Mbclark
What engine are you running and what type of temp sensor does the fan use?
Sorry about not replying sooner... I am running a 2.5L 4-banger. The Derale fan uses a screw-in temperature switch. You remove the temperature sensor on the thermostat housing and screw in a brass T-fitting. You then screw the temperature sensor into the side of the T-fitting and the thermostat switch into the end of it.
I like this design, but have become very dissatisfied with Derale. Within a week of installing the fan, The fan stopped working. I found that the temperature sensor went out. I was able to jumper this connection so the fan ran all the time the switch was on. I replaced the temperature sensor with one I bought from jegs.com. About a month later, the relay went out. I was on vacation out on a trail ride so just hard wired it to a switch (I know, bad practice, but it worked). A couple weeks later, the fan motor locked up.
Quadratec offered to exchange it... but I am done with this thing. I bought a fan from a Ford Taurus and have bolted it on and using a fan controller from Painless Performance. It uses the same type thermostat switch, so one component is ok.