Testing a temp sensor?

[Tractorcedric]

I am working on a Super C Farmall and had to replace the bad water pump. The water temp gauge was busted. I got a new gauge assembly and it did not read anything. The tractor was full of water and I worked it
hard on a burkley water pump for a couple hours. Still no reading, needle stayed at rest on peg. So I got another new gauge assembly and this time I just held the bulb end up next to the wood stove for a few
seconds and the needle moved. So I put it in and covered the radiator and let the tractor run for a while, even took it for a drive. Took the cap off and could see the water circulating and it was hot as well.
But the gauge was still not showing a reading. I have heard that some gauges on the market are for show only. If this is one of those, why did it read the heat from the wood stove? Bulb sensor goes into the
front of the head, right were the water returns to the top of the radiator. Thanks

 

[Janicholson]

To assure the gauges are correct, or faulty, use a sauce pan of water on the stove, and a candy thermometer as the water temp rises, the gauge should show increased readings starting at about 150 or so, and show overheat at oiling. Most farmalls are over cooled, and have a thermostat bypass that is too big. Cool running was thought to be good, but it is not. Jim

 

[matthies]

Don't be surprised that a new gauge is bad, More surprising to find one that works. Never seen one that works from Steiners.

 

[caterpillar guy]

It will probably never show temperature on the gage. They are so over cooled with radiator. Since it showed heat at the stove it works. Like Jim said if you need to know if it will read engine temperature, and is close to accurate. Then a pan of water on the stove and a candy thermometer to read with it. Much better than just enough if things are perfect in the cooling system. You would probably have to cover the radiator up, to get it to read on the tractor. We used to put a piece of old carpet over the front of our MD to get it to warm up at all in the winter. Never overheated. Grind feed or run feeding wagon haul manure in snow as deep as it would go. Usually put a bigger tractor on spreader if snow was very deep.

 

[Jim.ME]

Along with testing the gauge as recommended; use a non-contact infrared temp gun to check temps of the block and radiator. That will give you something to compare with the gauge readings seen in the water bath test.

 

[gene bender]

the way that engine is designed then a water pump you will have a hard time gettin the cxoolant warm enough to read anything on the guage Stick a therm in the radiator and read the temp and you will see why no reading on the guage

 

[BarnyardEngineering]

Not only that, but the location of the temp gauge on a Super C is not going to give you an accurate read. Normally the sender is installed in the head. On a Super C there's no place in the head for the sender, so it gets installed in the pipe going to the radiator.

 

[Russ from MN]

Like Jim said, put it in a pot of water on the cook stove, along with a cooking thermometer. My Farmall C doesn't have a gauge, if it's not steaming it's OK, and it never has overheated.