1950 FI Gauge Conversion
 

Hello! Working on a friends truck. He has re wired the truck and changed it to twelve volts. A voltage reducer is used to drop the voltage to the original gauges. The oil pressure works fine, however the temperature as well as the fuel do not. With key on ,temp gauge will bury itself below cold and fuel gauge stays on empty .( If you ground the sensor wire, it will go to full.) Checked voltage at gauges (6.4 ) and ground at fuel sending unit. Temperature sender resistance is approx.. 1.5 ohms cold. Any help appreciated.

Re: 1950 FI Gauge Conversion
 

Did the gauges work correctly before the change to 12v? The voltage reducer should take care of the voltage to the gauges, and if they worked on 6v, they should work fine on 12v (with the reducer). Is the temperature sending unit an original? If so, an ohms reading would be fairly meaningless. They work on current pulse, not resistance. If it has been switched to a resistance unit, I have no idea, but there may be a difference between 6v units and 12v units?? Again, no idea on that one.

Re: 1950 FI Gauge Conversion
 

Will check and see if sender (temp) is correct. When fuel sender is grounded, gauge will respond to full .
Thanks Again!

Re: 1950 FI Gauge Conversion
 

Is the fuel sender the original factory version?

Re: 1950 FI Gauge Conversion
 

The steel bus bars on the back of the cluster that tie together the 3 gauges nees to be removed, or swapped to other terminal, if not already done

Re: 1950 FI Gauge Conversion
 

Why would that be? Gauges shouldn't care about + vs - ground.