The OP says the gauge is mechanical type, this should be just a sensing bulb and a gauge. It wouldn't have an electrical coennection. Did I miss something? It may have an air pocket or the sensing bulb may be defective. You can test with a pan of hot water and a kichen thermoeter, the bulb should read the same.


~ Craig
1958 Viking 4400
"The Book of Thor"
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1960 Chevrolet C10
"A Family Heirloom"
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'59 Apache 31, 327 V8 (0.030 over), Muncie M20 4 Speed, GM 10 Bolt Rear... long term project (30 years and counting)

If you don't like driving yourTruck, you won't drive yourTruck..| Living life in the SLOW lane