79 Spirit Fuel Tank Sending Unit

Ford and Chrysler and maybe AMC use  the 10 ohms full 73 ohms empty units. I just put in a Jeep CJ tank in my Chev truck and because of the different sending unit had to also buy a gauge.

Tanks Inc. sell generic adjustable sending units of different ohm ratings but without the fuel pick up line. I think they have to be added by cutting an extra hole in the top of the tank.

Well, here's the update! Good news: The car is now running under its own power! The sending unit plugged right in, minus a leak at the sending unit, which I will correct next week when I can get some time in on my buddy's 2 post lift. That will make dropping the tank and putting gasket sealer on the sending unit a heck of a lot easier than laying on my back in the grass. I re-used the old gasket since it wasn't in too bad of shape and put oil on it so it wouldn't bind up and tear, but I guess I should have sprung for a new gasket. Bad news: It appears RonS is correct about the ohms. The gas tank read nearly 3/4 of a tank after dropping in about 3-4 gallons of fuel... For now, I'm pretty happy that I at least have a running and driving Spirit once again. I think if I can contact Summit racing again and see if a newer model fuel tank sending unit from maybe a square body Cherokee (I believe that newer body style started around 85-6 if I'm not mistaken) or a Grand Wagoneer from a little later might have the resistance I'm looking for to get the fuel gauge fully functional. Still some tweaking to do! I did have to modify the fuel tube as was pretty straight and not quite the same bends as my old sending unit. A few minutes with a tubing bender and it looked nearly identical! I also had to bend the float arm at a 90 degree angle in one spot, but I used the old sending unit as a basis for my bends and it looked about the same as well. I did also cut a bit off of the end of the fuel tube since it was a little longer than the older unit and I wanted the inlet to be at the same position. Everything else was pretty much plug and play with the exception of the lock ring being a little tricky to put back on. I will update this as I drop the tank and re-seal the sending unit. I may just buy a new gasket and lock-ring just to be absolutely sure this thing seals into the tank. When I went to the parts store (Autozone) to buy the tubing bender, they informed me that they had a complete sending unit in stock for a 79 Jeep CJ-7 with the lock ring, gasket, and sock all included for the same price as the Summit Racing unit without the shipping... Oh well. At that point I had already modified the Summit racing unit and there was no chance of returning it. You live and you learn I guess! Here are some photos of the before and after on the sending unit. I ended up getting the Omix-Ada unit with part number 17724.11 and modifying it as you see below. 

I was not aware that AMC changed the ohms on the sending units. I have only played with 1966 and 1974 models. I know for a fact they are 10 Full and 73 empty.

You did a great job modifiying the new unit....you can use it if you put in a aftermarket gauge. I am sure that's not an encouraging option... You just received a couple of blows in this round...but the fights not over yet....

When it comes time to play with my 83 Concord, I will remember that.

Having AMC Fun,
Ollie