How to Solder a Filler Neck

While waiting for the fuel sender to arrive, I wirebrushed the tank and then soldered on the filler neck. I used a propane torch, flux and 50/50 solder. The 50/50 solder has less lead in it so it is stronger than normal 60/40 solder. The tank had been sitting for about a month and I couldn't smell any vapors but I again blew out the insides with both the air hose and shop vac.

First I wirebrushed the filler neck tank openning and put a liberal amount of flux where I wanted to solder. I then tinned the area to make sure that the solder would stick properly. I used a hand wire brush to brush off the excess hot solder. At this point it was easy to see any areas that were dirty where the solder wouldn't stick. More wire brushing and flux, re-tinning until it was perfect. Once the area around the filler neck openning was shiny like chrome, I was ready to solder on the filler neck. I treated the bottom side of the filler neck where it makes contact with the gas tank to the same tinning process.

Just a note: make sure that the part is sitting level when you solder. If it is at an angle, the solder will flow off. I had to jam my gas tank against the garage door and tilt it up against a box to compensate for the angle of the filler neck openning.

filler neck

The filler neck after it had been soldered and painted a lovely aluminum.

Gas Tank

The repaired and painted gas tank! (Note, this is a mirror image so you can compare with the next pix)

Correct filler location

Here's the filler neck resoldered in the correct position..... whoops!

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Copyright April 2011 Eugene Blanchard