How does this work?

I have had an electrical Auto Meter water temp. sensor for a long time now but have never installed it. About two years ago, I tried to tap into the intake where the stock 'temp sensor' not 'sender' is, and ended up stripping that nut. I have found a way to fix that though ...

What I am wondering is how a electrical water temp sender (autometer) actually works? I lost mine when I stripped the intake back in the day (probably threw it as far as I could) but I am tired of looking at a gauge that does nothing. I would like to fabricate a sender (they just look like a piece of brass). If anyone has any knowledge regarding how they work .. how about enlightening me..:SNSign:

Yeah, calling autometer for a new one was my first thought but my stepdad works with valves, regulators, etc.. and has a lot of spare fittings and such so I thought I'd try. I am still curious as to how it works though if anyone knows. Does the brass in the 'sender' just warm to the temp of the water and then the wire running to the guage acts as a thermometer? This isn't a big deal, I would just like to know how it works...

propellerhead said:

The sender is a thermistor, which is a resistor that changes its resistance when it reacts to temperatures. Feed it 12 volts and measure it, then map each resistance value to a temperature. Each manufacturer may use different thermistors so you generally cannot swap one for another. Because of how thermistors work, it it very important that you wire it in per the manufacturer's specs, or you could be adding resistance and getting a biased reading.

Click to expand...

Thanks, I get it.

I will order another one like svttech76 and 40oz mentioned. Just trying to get creative (and cheap lol) but the sender is cheap anyway. Thx for the info people.