When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
Hello I have a 1977 ford f250 with 351m and I have my temperature sensor on the passenger side next to the timing cover but I’m wanting to add a temperature switch sensor for electric fans and I was wondering if the top of the thermostat would be a good place to put that sensor?
It could work, but the thermostat will interfere sometimes with the flow of coolant around your sensor. There should be a pipe plug in the water pump under the heater hose. I used that location on a cleveland. One important thing to keep in mind, if you place your sensor in the water pump, you will be measuring coolant temp as it enters the engine. Still usable, but only if you have an adjustable fan controller. Another option, if you don't have a shut off valve in your heater hose, is to use an inline sensor in the supply heater hose. Ford rangers and 2.3 mustangs in the 90s used this location for the ECU coolant sensor. You could easily grab an inline temp sensor housing from your local scrap yard. I would ask though why you want to install electric fans? Running hot, looking for more power? My two cents, get a shroud and a good clutch fan. There's a great episode of engine masters where they test power loss from various fans, and a clutch fan was surprisingly efficient. Also, for all around never worry about it reliability, an engine driven fan is the way to go.
Last edited by Drivewayfabricator; Apr 11, 2024 at 07:34 AM.
Reason: Added opinion about electric fans.
Why risk a fan that may not come on, over heat the motor and maybe pop a head gasket?
There is nothing wrong with the factory cooling set up so why change?
Dont say for more power this is not a race motor is it?
All you would be doing is now using power to turn a higher out put ALT so what did you save?
Oh if it is to keep your motor cooler as it runs hot now, install a radiator shroud.
Fan blades need to be half way in the opening, not all the way in or out.
And about 1 inch from the blade tips for the fan to pull air through the radiator.
There is a good video on YouTube of a guy making one for a stock car that looks easy to do at home with a few tools.
That is if no one makes one for your truck.
Yea I am not a fan of electric fans unless it is a race motor and has a electric water pump also.
Dave ----
ps if you go electric fan put the sensor in the lower hose or bottom of radiator like a lot of factory cars have it.
The only time the fan would come on is if you are stopped, no air flow thru radiator, and the temp went up a little.
You want the fan(s) to come on if the radiator did not pull enough heat out, no air flow, and it can only see that as the cooler coolant enters the motor.
