i have a new proform and my dad hooked it up to a switch which is now going haywire on me how did you guys hook your up for it to come on automaticly when the radiator gets hot?
Well you can do it a few ways. You can get a engine coolent fan switch set to turn on at the temp you like. 185 is good. Then find a place either in the intake or on the thermostat housing where you can drill and tap for the sensor. Connect it to turn on a relay. Connect the fan to the power side of the relay.
The other is using temp probe that goes into the radiator. Hayden sells them at any pepboys.