Electric Fan T-Stat Switch

jeepjoe43

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Just doing a little homework here.
Does anyone know the appropriate temp range for the fan switch with a 195 t-stat?
I was looking at an on at 205, off at 195 unit, does that sound right?
Makes sense in my mind, but I'm not an expert.
I'm pre-wired for 2 terminal unit, any suggestions?
 
With that range I'd put the sensor in the upper radiator hose or at the top of the engine to sense the coolant at it's hottest point, but I would think that would work. You'll have cooler fluid than that coming into the engine from the radiator, which is a good thing.
 
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With that range I'd put the sensor in the upper radiator hose or at the top of the engine to sense the coolant at it's hottest point, but I would think that would work. You'll have cooler fluid than that coming into the engine from the radiator, which is a good thing.
A friend of mine recommended putting it in the heater hose to the core.
I'm also looking at a PWM (Pulse Width Modulated) variable speed fan controller, though not very seriously.
I do have industrial experience with this concept, but not sure how that would work with thermostat.
But it cost's a lot more than a switch and would be more unwanted electronics.
Just doing homework. A toggle switch served me well for years.
 
I'd put the temp sensor as close to the engine as possible, but I don't see why that wouldn't work. Just make sure you get it in the send line, not the return. It would take a relatively hefty PWM/FET unit to run a radiator fan; those things pull a lot of current. I'm not sure the fine control would be worth the effort.

I've thought about getting an Arduino (or similar) microcomputer and programming it to run the heater fan, auto-on for the lights, wiper delay, and several other things of that nature, just for fun.
 
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I'd put the temp sensor as close to the engine as possible, but I don't see why that wouldn't work. Just make sure you get it in the send line, not the return. It would take a relatively hefty PWM/FET unit to run a radiator fan; those things pull a lot of current. I'm not sure the fine control would be worth the effort.

I've thought about getting an Arduino (or similar) microcomputer and programming it to run the heater fan, auto-on for the lights, wiper delay, and several other things of that nature, just for fun.
They do pull a lot of current, but it looks like it's built for it, again, I'm not seriously considering it.
The only fan failure I ever had was the relay, couple lengths of wire and some crimp connectors, good to go.
I had spare relay, but it got smashed to pieces in my tool box. I've learned a bit about packing a Jeep since then.
Thought about Arduino route as well, that's similar to how my Grand Marquis works. It's actually pretty convenient.
But it's a Luxo Cruiser.
I think simple is better, especially out in the bush.