Who knows about "thermo-fan switches"?

[Sodo]

I have a '51 Willys pickup with a '79 258ci inline six. There is no fan on the waterpump, only an electric fan ahead of the radiator, with a manual switch. It's easy to forget to turn on the fan - I'd like to install a thermo switch. Yesterday it blew all the water out because I forgot, I really need to get this setup before I blow a headgasket. These switches are all over Amazon, but don't list specs. For example, can it switch a fan al by itself, or does it operate a relay? And what thread is it?

If anyone out there KNOWS the switch and components to use, and where to put it, that would be great help. I do have a steel elbow ahead of the waterpump that I can weld a nut or NPT fitting onto.

I'd like to get a narrow fan to put onto the waterpump, and remove the electric fan entirely, but may have to do this electrical mod until I can find the right fan.

 

[the old grind]

No harm in wiring a relay to run the fan whenever the ignition is on, is there? (A belt driven fan spins whenever running.) We've jumpered electrics this way as a band-aid 'till the temp switch & circuit were checked out. Some just stayed that way for years vs going that far but the thermostat should keep the engine up to temp without over-cooling.

Electric fans ahead of the radiator seem less dependent on shrouds to work effectively vs using a 'stock' setup, & that 'six' may not leave much space for the the latter. btw, setting the blades within an inch of the radiator won't always make up for not having one, and being any closer risks the worst when on the trails and the frame 'articulates' the least bit.

 

[Winmac]

With a rad fan you want to control the temp in the radiator, typically the sensor is on the bottom of the rad on the return side.

 

[Jimbrown]

Take your pick.

https://www.google.com/search?q=how...F95-guide-how-wire-up-thermofans.html;575;428

 

[Sodo]

With a rad fan you want to control the temp in the radiator, typically the sensor is on the bottom of the rad on the return side.

Thanks for your help. Finally had time to look at this project again and I think the best course of action is to have the radiator outlet moved (at the bottom of the radiator) to provide clearance for a normal fan on the waterpump. The electric fan is just another 'system' that I don't really want on this '51 truck, also it's visible thru the grill.

 

[downsizingnow48]

Great old pickup you have there! I had a 1956 Willys 4wd wagon for a few years, same thing mechanically. Drove all over the southern California and Arizona deserts, never had a heating problem with the stock radiator/fan/water pump.

 

[jaotguy]

drop by a wreckers and pick up a ballast resistor from a Ford Taurus / Sable ..., should be sitting between the motor and the trans ... rectangular thing ....

it is the speed reducer for their electric fan ( low speed ) ....

wire it in directly across your "switch " so there is always power to it when the vehicle is in use ... low speed.... and you can switch to HIGH by flipping the switch ....

 

[FTG-05]

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

 

[Sodo]

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

:applause::applause::applause:

That ABSOLUTELY rules. Ordered it immediately. This will give me time to find a fan and then move the lower rad outlet. Radiator has a 2nd (blank) "spot" (alternate outlet location).

I wonder it it's easy to DIY, it's just regular solder, right? Just heat it up and pull it off, then cut a new hole, cover the old hole? Cut some brass from another radiator to cover the old hole?

 

[buickanddeere]

Temp switch is to measure coolant temp leaving the engine before the rad. Not the temp when leaving the rad back into the engine.
Too cold causes problems. 195F stat with 50/50 mix and set the fan to spin at 210F.