Hi people. I have an '88 F-150, regular cab, 5.0 litre, on propane. I have had hell of problems trying to get a fuel gauge to work on this. There is one (1) guy in pretty much a 200 mile radius of me who carries propane conversion parts, he figured the sender should be 70 ohm to work with the gauge. I bought a sender from him, tried it, it was not the correct ohmage. It showed empty on a tank that was at least 3/4 full. (the gauge does move when I take corners, etc, propane sloshing around, so I know the sender is good, just not the right ohmage) The sender that was originally on the tank was basically broken, didn't do anything, and after I took the new one back for the correct one (and found out it was the only one he had in stock) I re-installed the old one and it almost wants to work- it goes to 1/4 tank (the tank is over 1/2 full right now) and does make the gauge move a bit around corners.

Sorry for that long setup to a simple question, but what ohms should the sender be?

Also, strage as it may sound, I think the 70 ohm one was correct, but 'backwards' or something... the float/sender unit is on the driver's side of the tank, so taking a hard left turn would slosh the propane to the passenger side, and *should* make the gauge go down, right? It did the opposite. Would it be possible to just switch the polarity of the gauge so it would work with that 70ohm sender? I can't really wait for a couple weeks for this dealer to look it up and order the correct sender for my truck.

Not knowing how much fuel you have is pretty scarey on a propane-only system.