Who knows about "thermo-fan switches"?

[Sodo]

Interesting, thx. But all it does is run the fan. The thermostat will control engine temp much more authoritatively. If it senses the water temp coming right out of the engine, it will turn the fan on sooner, that's probably what I want. Right?

I bet it never actually turns the fan "off" in use.

With a thermostatic switch I can start the engine, move the truck, and shut off, where the fan never runs (if cool). And all the alternator power goes to replenishing the battery (as opposed to a simple relay that runs the fan every time the key turns on). Not be the best thing for an engine but that's the usage this truck will see (farm type usage).

 

[buickanddeere]

Interesting, thx. But all it does is run the fan. The thermostat will control engine temp much more authoritatively. If it senses the water temp coming right out of the engine, it will turn the fan on sooner, that's probably what I want. Right?

I bet it never actually turns the fan "off" in use.

With a thermostatic switch I can start the engine, move the truck, and shut off, where the fan never runs (if cool). And all the alternator power goes to replenishing the battery (as opposed to a simple relay that runs the fan every time the key turns on). Not be the best thing for an engine but that's the usage this truck will see (farm type usage).

If you set the fan stat too low the fan will run constant. That is why I said 195F engine coolant stat and 210F fan electrical thermostat.

 

[Sodo]

If you set the fan stat too low the fan will run constant. That is why I said 195F engine coolant stat and 210F fan electrical thermostat.

It turns the fan on at 185deg. Probably actual water temp is higher than that. Highly doubt the fan itself can keep the temp below 195. Just want it to be automatic on/off and not run just with the ign. key.
Do you think it should be outside of the ign. key? I guess I can try it and see how long it runs after engine is shut off.

 

[buickanddeere]

View attachment 382608
It turns the fan on at 185deg. Probably actual water temp is higher than that. Highly doubt the fan itself can keep the temp below 195. Just want it to be automatic on/off and not run just with the ign. key.
Do you think it should be outside of the ign. key? I guess I can try it and see how long it runs after engine is shut off.

I don't understand what you are saying.
If there is enough airflow through the grill while driving or just putting around on a cold day. There is no need to operate the electric fan. Set the electric stat to start the fan at 210F. Use a 195F coolant stat inside the engine.

 

[Sodo]

Doubt that the switch is adjustable, looks like its simply 185deg.

 

[FTG-05]

Sodo, look around at the site that I linked to; they have adjustable ones but they were more expensive. For this application, I see no need for an adjustable switch. Good luck!

 

[justme23005]

This one works good and its easy to install, since you can just zip tie the sensor to a radiator hose.. And its adjustable.. Factory Air System Mounted Adjustable Cycling Temperature Switch 35845: Search no more for the best A/C Clutch Cycle Switch at Advance Auto Parts

 

[Sodo]

(ooops edit!)

That's an air conditioner thermostat that clutches your air conditioner pump somewhere in the (cold) range of 30-50 degrees.

Need adjustable switching that will close a switch somewhere in the adjustable range of 175-210 degF.

 

[justme23005]

I used one on my 4wheeler to run the electric fan, and it lasted a few years before it turned to crap, after I let the 4wheeler sit outside all winter. not trying to derail the thread, but here's a video of the 4wheeler.
DS1000 - YouTube

 

[Sodo]

$31 from Perma Cool: Electric Fan Thermo Switch Kit (Tie Wrap Mounting)

I installed this switch, zip-tied it to the thermostat housing. It works perfectly, fan turns on when the engine warms up. Also moved the lower radiator outlet, project described in other thread with pics.