rusty tankfiller cap

[HansLab]

Hi all,

Now that I'm covering my right wing (the only one containing a tank) I removed the cap, only to find out htat is is a rusty mess underneath.
I cleaned the tank (according to S60) and rinsed with water (because my tank was one of the types that are not supposed to be cleaned with acetone - but that is at the end of the service letter.... I know, I know...)
Althouhgh it had a good dry period with the cap off, the water vapor must have done its job, as well on the cap as on the filler-neck.
Now what can I do? Clean it up and put some kind of varnish onto it? The rusty particles now are falling into the tank....

Any advise will be very welcome....
You may even laugh about this one (a bit)...

hans

[Tom Waid]

Same thing happened to me. I followed the instructions and rinsed the first tank with water. I thought I had thoroughly dried it before I taped over it, but apparently that was not the case. In a few weeks the filler neck was rusted. About that time the new advisory recommending an acetone flush was published. I cleaned it with a wire brush and inspected it. There was some pitting of the filler neck but not enough to weaken it. Of course I now had a tank full of rusty particles. I cut a piece of clear plastic tubing that was narrow enough to extend down through the filler neck and long enough to reach every corner of that part of the tank. With some duct tape I fitted this tube to the hose on my vacuum cleaner. To avoid having the free end attach itself to every flat surface I notched it. This worked pretty well but, of course it did not get every particle. I then rinsed the tank with acetone until the liquid coming out of the tank was free of debris. The other tank was rinsed with only acetone and I had no more problems with rust.

When the plane is assembled and before I start the engine, I'll obsessively flush the fuel system and pay special attention the tank that collected rust. I also intend to frequently change the fuel filter during the first hours of engine time.

If your tank is not to be flushed with acetone perhaps you can flush it with gasoline.

Good luck.

Tom

[Dorsal]

Also had the same problem and approached it much the same as Tom complete with arthroscopic vacuuming. I did use a chemical rust remover that worked pretty well.