I have a 55 Ford converted to 12 volts.  All gauges and senders are original.  Gas gauge reading corrrect.  The problem is the temperature gauge reads almost all the way over to Hot but engine is not hot.  Prior to installation, temp gauge tested correct using 1.5 Volt battery.  The temperature sender is fairly new but had a high reading prior to converting to 12 volts.  Any suggestions?  Thanks, 

Gary

Do you have a regulator in the instrument circuit to drop the voltage from 12 to 5 volts?

John - "The Hoosier Hurricane"

I'm prettty sure the wiring is stock and there is no voltage regulator in the circuit.  Current goes from ignition switch to temp guage and fuel guage.  From the other temp guage terminal,  current goes to temp sensor in block.  The other fuel guage terminal goes to fuel tank float/sender.  Thanks

Gary

After '56 Ford installed the instrument voltage regulator in the hot line between the ignition switch and the gauges.  Post '56 gauges are 6 volt, as is your '55.  A regulator in the circuit should solve the problem.

John - "The Hoosier Hurricane"

Hoossier,

Thanks for the info!  It will be so great to get the thing reading correctly.  I really appreciate your help.

Thanks,

Gary

Hello Gary! in case you are not familiar with the regulator mentioned,it is basically a set of points which open and close.12 volts in and the average out is 6.If you go on Ebay item # 200510622204 is what you are looking for.The suppliers like Macsantiqueautoparts and Concours sell one to.Its solid state I believe and more expensive.Does the same thing-12 volts down to 6.