The Stovebolt Site Forums The Shop Area Engine Shop 248 GMC temp. sending unit for GMC COE

A Standard brand sending unit (Part# TS-6) corresponds correctly to my original temperature gauge. Needed no bushings and is as original as I can get. Hope this helps someone else out.

Good info on the sending unit. However, replacement parts are not "original".

Hi John,

What year is your COE? Depending on that answer, is it 6 volt or 12 volt?

Thanks, Jeff

Ayup thats true.
But I`m just plum thrilled, to have a correctly registering temperature gauge after having none. So I`m not to worried about correctness yet. I`m just hoping this info may save someone else the time and trips to the FLAPS I took to find a workable unit. Correct or not.

My truck is a 1949 GMC COE 248 engine. Engine is a 1955 GMC Factory Replacment. (noted on the yellow sticker under a layer of crud on the valve cover.)Installed probably back in the later 50`s so the truck isnt a candidate for "originality" award category. ( to see the truck as I found it, Go to . WWWhotrod garage.net look under sold trucks, stk# 1155) I`ll try to get a phooto of it after refurbishment posted soon.

I converted to 12 volt alternator, negative ground. Gauges rebuilt by D&M restorations in Greenville SC.
If I under stand correctly the temp/fuel guage doesnt care if its six or 12 volt as it works on resistance not voltage. If Im wrong pleeeaase correct me.
Sending units are measured in varying OHM resistance, not voltage. So finding to correct unit was a hit and miss search to find the correct range as they all vary in range model by model widely. Thats was more than a few trips to the FLAPS who was kind enough to let me peruse his older books out back and try to make educated guesses. Is the sending unit correct to the truck? No. Does it work as a replacement? Yes. Am I happy to see the needle rise and fall as appropriate? You betcha!! Would I replace it with an "original"? No, not that ambitious.
John Drabik

John, I was referring to the use of the term "original". Original means with all the parts it left the factory with. It is highly unlikely there are any "all original" trucks from the '40s and '50s. A truck with OEM replacement parts would be "factory correct" but not "all original".

You are correct that the sender works by variable resistance.

Thanks Cletis, I`m understanding a bit more betterer. Seems the words "all original" "restored" "reeconstructed" "reconditioned" are easily mixed up and all mean something different.