Acid De-rusting Tank

[jjwaller]

Hi Folks:

Got a bad problem with my '78E tank.
Troubleshooting fuel problems on the poor neglected beast, when I finally looked in the tank and...Oh My God!
Bikes been sitting up for about a year while off working and concentrating on the Hondas, finally going to get it running.
Question is, with the Phosphoric acid solutions that it's been said work real well, how have you dealt with the petcock and filter on the 78 E's. Does it not eat the plastic? Or what am I missing.

Thanks
John

[HobbyMan]

It may not eat the plastic but it may start to eat the aluminum petcocks. I found that if you are going to do this, it is best to plug the holes. I took some scrap metal and used flat peices of rubber as gaskets. I just made the holes in the metal for the screws, laid the rubber over the holes for the sending unit and petcocks, punched the screws through the metal plate and rubber and tightened. You do not want to have any leaks whatsoever. Be careful not to get anything on your paint. There is another method of using washing soda and electrolosys to remove the rust. It seems a little safer.

[jjwaller]

Thanks for that.
I may clean it out good with acetone and nuts and bolts and see what it looks like.
Then, maybe Evaporust or I'll look into electrolysis.

[HobbyMan]

I must put in one word about the nuts and bolts. I did this same thing on one of my bikes but I wasn't thinking when I did it. I shook the tank. BIG MISTAKE. There are hundreds of tiny "reverse" dents in the tank. If you are going to put anything dense in there, just make sure you only slide it back and forth. As an alternative, I have used fish tank gravel. It is a little more difficult to get out when you are done but it does not damage the tank.

[Ken Talbot]

There's another variation using molasses. See this old thread

[jjwaller]

Yes, Iv'e been pretty much through all the de-rusting threads on this and the SOHC4 forums. I don't have the time at the moment for the slower but less destructive treatments, not to mention re-painting the tank. for the more radical stuff. At this time, I just flushed out the tank real well, and am installing fuel filters.
I'll monitor them carefully. Hopefully, this is the last time I have to do the carbs!
Thanks