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
