Willys Truck Gauge Clusters

[dgoodenow]

Guys: I'm redoing a 1952 Willys stake bed truck, see attached, and I am having trouble with the temperature gauge. The truck starts and runs well, but after a few minutes the temp gauge pegs to hot. I have replaced the water pump, thermostat, 6 volt sending unit (it is still a 6 volt system), and the radiator. It still shows hot, but I have had two inferred temperature guns on it and it never gets above 190 degrees, even after running for an extended time at the stand still. My parts book shows what is called a voltage regulator that mounts on the back of the instrument cluster and the output side goes to both the gas gauge and the temperature gauge. I put in 5 gallon of gas after cleaning the lines and replacing the fuel tank, and the gas gauge showed about 1/2 full. I think this is also high for a 15 gallon tank. I tested the voltage regulator on the gauge cluster and I get the same reading in as out, all above 8 volts. I'm thinking this device is not working properly, any thoughts? Thanks.

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