You get something like this Davies Craig Adjustable Thermo FAN Switch DC 0401 | eBay.Hi,
I've been reading this forum for advice on which D1 to buy, then bought a 1998 in September 2013. It has 116k miles and needed some work. The frame wasn't rusted and the engine/tranny seem good, radio comes on when it feels like it. The guy I bought it from installed two large electric fans behind the radiator and they run ALL the time. The good news is the engine never overheats, the bad news... it's 10 degrees outside and they are still running. Ha. My question is; where can I splice the power wire to the fans into the coolant temp sensor so the fans only come on when the temp exceeds 180 degrees and turns off at 170?
The sensor slips in the top radiator hose where it clamps onto the radiator. You then run the trigger wire for the relays running the fans through this switch. The switch is adjustable so that you can have the fans switch on at what ever temp you want