Ok, this may sound crazy, but it came to me in a semi-conscious dreamlike state, you know right before you doze off. I got the idea after I replaced the thermostat in my house hot water heater. Anyway, how about using the upper adjustable water heater thermostat to control an electric cooling fan? Looking at the unit I got from Home Depot, the contacts are rated at 25 amps, and is adjustable from 90 to 200 deg F. you would have to mount the unit flat against the radiator though. You could use the lower stat but would have to have another relay to convert to normally open. Comments?

I think as long as you could put it directly against the radiator, and block airflow through or across it (so that you get a correct temperature reading at the unit) you could do this.

I have not seen what the thermostat you have looks like. Is it possible to remotely mount the unit somewhere else with a temperature proble installed at/on the radiator? This would be a very economical way to come up with a fan controller.

Please let us know if you figure out a way to make it work.

I

That's 25 amps @ 240 volts, right?

If you wanted to do some experimenting with something like that there is a wide variety of much smaller sufrace mount hermostats available.

I would think using a submersible type TS would be a much more desirable way of sensing coolant temperature.

or you could just buy a tfs switch in the range you want, cut a piece of exhaust pipe to fit use as a coupler where you cut the radiator hose, weld a bung in it and then you have your switch :) oh, paint the coupler black so you can't see it too well, can you guess who did this