Will a 24 v fuel gauge read on a 12 volt feed? I guess what I'm asking does it measure resistance so would it measure half full? I'm changing from 24 V system to 12 volt and fuel gauge is 24 volt I'm hoping I just need to change it and not sending unit in tank. Any comments?? Bob-------- Explanation:: other than a few gauges I find myself no longer in need of the 24 volt side of the system. I no longer have the big 24 volt ac system or 24 volt starter, defroster motors or windshield wiper motors. All lights are 12 volt. I could retain the 24volt system or just replace a few items and simplify everything by making all 12 volt. Bob
You could get an inexpensive 12V to 24V converter to run gauges, if you needed to.
Brian
You will have to know the resistance range of the sender, then you can replace just the gauge.
Most of my 24 volt gauges just have a resistor on the back that drops voltage to 12 volt. A fuel sender is simply a variable resistor in most cases and doesn't care about voltage. If you do what Len says and get a 12 volt gauge you should be fine as long as you rewire everything to 12 volt.
Most 24 volt fuel gauges are 33 to 240 ohms the 12 volt fuel gauges seem to be 0-90 ohms
I'm following both post and checking as we go in bus. Makes sense . Nice to be at this point of catching up on details and having help! I can actually think of a start up soon. 2years has past. from a salvage shell with no drive train. What will I do when it's done?? House Work-- So just caught LB post-- need to think a little more. Bob
One can purchase 12 or 24 volt fuel gauges in just about any resistance range one wants. Some may not be as readily available as others.
There is no need for Bob to buy a gauge or a sender for fuel he can take a pencil and wrap the wire around the pencil to set the resistance ohms just about all buses use 12volt gauges through a shunt and resistors
I gave the ohms from a 24v Prevost and a 12 volt Eagle he can make it work without buying anything except the light blub which I know he can
All the modern gauges and lights on the dash are controlled by a little black box mounted on the frame it could care less you set that with a laptop
That is were people get into trouble buying dash gauges from a truck from 2000 on they don't work without the little box