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RustyPile · 08-13-2022, 01:56 PM

I bought my '71 a little over four years ago as a "non-runner". It had sat for years out in the weather, so it had several issues. One of which was a fuel gauge that didn't work. When I removed the tank for cleaning I discovered the sending unit was in bad shape, rusty with a partially dissolved brass float. I replaced the sending unit and within a few months the float developed a leak, filled with gas and sunk. It had separated at the seam. I replaced the float with another brass unit. Within a few months, it also failed. I had a couple discussions with the online vendor I bought it from, and they sent a complete replacement unit. I examined the unit closely to see if I could find out why the floats are failing. The float seemed to be clamped awfully tight in the loop at the end of the arm. I opened the loop enough that the float would stay "captured" but loose enough that the float would "rattle" a bit in the loop.. I installed the "modified" sender over 4 years ago.. I have not had any more trouble with it..

About a year ago, I installed a new mechanical fuel pump with a return line. I removed the sending unit to install a fitting for the return line. There were no signs of deterioration of the float or other components.. I believe the problem lies with the float being clamped too tight to the arm. Solder is not strong, it's just a bonding agent. It is my belief the constant pressure causes the solder to crack and fail.

08-13-2022, 01:56 PM	#12
RustyPile Registered User Join Date: Dec 2017 Location: Elkhart, Texas Posts: 1,565	Re: Bad brass float I bought my '71 a little over four years ago as a "non-runner". It had sat for years out in the weather, so it had several issues. One of which was a fuel gauge that didn't work. When I removed the tank for cleaning I discovered the sending unit was in bad shape, rusty with a partially dissolved brass float. I replaced the sending unit and within a few months the float developed a leak, filled with gas and sunk. It had separated at the seam. I replaced the float with another brass unit. Within a few months, it also failed. I had a couple discussions with the online vendor I bought it from, and they sent a complete replacement unit. I examined the unit closely to see if I could find out why the floats are failing. The float seemed to be clamped awfully tight in the loop at the end of the arm. I opened the loop enough that the float would stay "captured" but loose enough that the float would "rattle" a bit in the loop.. I installed the "modified" sender over 4 years ago.. I have not had any more trouble with it.. About a year ago, I installed a new mechanical fuel pump with a return line. I removed the sending unit to install a fitting for the return line. There were no signs of deterioration of the float or other components.. I believe the problem lies with the float being clamped too tight to the arm. Solder is not strong, it's just a bonding agent. It is my belief the constant pressure causes the solder to crack and fail.