CJ5 fuel gage sending unit.

[ChuckD]

I have a 59 CJ5 and replaced the speed-o that has the fuel gage on it. The fuel sending unit looked in great shape so I kept it and it seemed to work great. However, now that I’m driving the CJ, I see that the gage stays on full forever and then drops to half and then empty very. I was thinking I needed to slightly bend the float arm up so the arm will drop sooner as the fuel level drops. Problem is if I’m going to do all that and the real problem is a bad sending unit, I’m just doing twice the work. Has anyone else seen this problem? Do you think my sending unit is going bad? Do you think bending the arm up will help the problem?

 

[JR74CJ5]

Hi Chuck,

Not sure, but from your post it seems like the gauge is moving through its full operating range (full to empty) just not "correctly"...

If you bend up the float rod, you'll adjust full and empty levels... When I tried to put a "hidden gallon" or two in my tank by having the fuel gauge show empty earlier, It would no longer show fully "full" on the gauge. The float would hit top of tank before allowing the sending unit to be at the full point...

Does any of that make sence?

I believe you either need to clean up the contact area good (on sending unit / float area), or replace...

But I'm not positive!




~ Jr

 

[ChuckD]

Thanks JR,

Good point. I’m going to work on it this weekend. I was thinking, if I do this with a full tank and bend a little, set the unit in place, check the gage… repeat until I am just at full it may work. Right now the gage is really kinda past full when the tank is full. I’m glad I left my tank in the stock position under the seat so it’s easy to get to. Just have to remove 4 bolts to take out the driver’s seat.

Chuck

 

[JR74CJ5]

You know also I was thinking that tank is larger (capacity wise) at the top than it is at the bottom. So it would be slower moving from full to half than from half to empty...

I have one under my seat (and one in the back too) and have been looking for the sending unit for the under seat one (though admittedly not hard... lol)

Let me know what you find out bud!


~ Jr