Hello and Happy Holidays to all,
Still having some trouble with the gauges on the 53 F100. The Fuel, Oil and Temp all read high, and have replaced the sending units, thermostat, etc. Finally got a mechanical oil pressure gauge, and it's reading around 50 psi (!). Anyway, now I am wondering if I have too much voltage going to the gauges, or if there is an open circuit/short.
I checked the back of the fuel gauge, with a meter, and there was a 2.5v difference between the posts (for what that's worth).
The wire coming out of the ignition switch going to the instrument cluster is 6 volts. There is nothing in-line between it and the gauges, so they are getting 6v. I have looked all through my shop manual, and haven't seen any mention of a 'voltage stabilizer' or 'reducer' mentioned. I have seen them mentioned in catalogs for '56 and newer models, but nothing for the 6v '53.
Does anyone know if those gauges are designed to work at 6v? and if there is supposed to be any kind of reducer/stabilizer on the instrument cluster (in-line between the ignition switch and the gauges)?
The Fuel and Oil are pegged over High (they move slowly over - they don't just jump over), and the temp is reading about 3/4 hot (it's running about 155 degrees - checked with a thermometer).
I'm really out of ideas now. If anyone has any ideas and/or info on what voltage the gauges work on, I'm ALL EARS! Thanks!

 

Your guages are designed for 6 volts. They don't use a reducer or constant voltage regulator,THe CV reg limits 6 volts to the guages, even with a 12 volt system,
Which started with 12 volt guages and lasted until 1986 when Ford switched to a different design guage. The guages move slowly when they are powered.

Barry

50 F-1