Testing/Adjusting Fuel Sending Unit Arm

[Dandesjar]

It looks like my newly installed fuel sending unit has developed a leak at the o-ring while in storage over the winter and I'm going to have to drop the tank and get the leak sorted.

I installed the sending unit without testing the readings before re-installing the tank and, while it isn't too bad, it doesn't read as accurately as I'd like. So I figured I might as well take the extra time to adjust the float arm while I have the unit out again.

My question is... Is there a simple way to accomplish this that I'm just not thinking of? Or do I literally have to re-installed the sending unit and then fill the tank to various levels while reading the gauge and then keep pulling the unit out to tweak the arm and fine tune it?

This sounds messy and tedious... is there an easier way to dial it in?

Thanks for the help

 

[blubuckaroo]

What I did was to bend the float arm so swings in within the parameters of the tank.
With, the tank on a level surface, use a square with a level, a tape measure, and some guesstimation.
Is this stock or aftermarket tank?

 

[Dandesjar]

Well... good question... I know it’s not the original tank for my ‘71. It’s a poly tank for a ‘77 and I’m not sure if it’s original or a reproduction tank.

 

[blubuckaroo]

I'm actually going to be going through this again on my aftermarket aux tank.
It's developed a leak. No gas dripping, but a really bad odor and gas stain on the tank. I'm hoping it's just a sending unit gasket and not a seam weld. I'm waiting till the tank is empty.

 

[blubuckaroo]

Well... good question... I know it’s not the original tank for my ‘71. It’s a poly tank for a ‘77 and I’m not sure if it’s original or a reproduction tank.

Good luck with that.
Two leaky poly tanks is why I replaced both on my '77 40 years ago. It wasn't the gasket, but a crack in the tank where the sender unit goes. I tried to fix it with JB Weld, but it still leaked.

 

[cs_88]

I bent the arm on my replacement fuel sender for my aux tank to get better readings when the tank is full.
Definitely better now.