RD350F1 fuel tank leaking

[petteri]

I have a leaking fuel tank. It put me off from fixing the bike for many years since the repair would be an A** to do properly.
Well I got the inspiration to get the bike going and succeeded somewhat in that.

I put epoxy on the inside of the tank and rode happily for a month. Now it is again seeping from the same place but very slowly. I take it that the epoxy is starting to fail but not all the way since the fuel isn't pouring out like it did.

What do you think could be done to save the tank? It has dents that should be flattened anyways so a repaint is necessary no matter what.

I was thinking of just taking a grinding tool and cutting the whole damn bottom off, then torching the epoxy away and welding the rusted part out with new thick steel. With any luck the sides aren't rotten below the paint and can be salvaged.

If the weld is successful then would sealing the tank with POR or the like prevent more rotting in the future?

I can work with metal in some degree but haven't done any real metalwork in years. One could call my skills a bit rusty. For example I manufactured a new fuel tank to my moped from steel a few decades ago.


I looked ebay, japans yahoo auctions and didn't find any usable tanks for less than 2000 euros! Even those would have to be repainted to my colour and I just couldn't do it to an excellent condition tank. 

These fuel tanks are making me sad 


 

[red998]

I had a leaking tank on my Ducati and the tank came off a track bike that someone had crashed and the tank had been ripped off and it had slid along the track wearing through the welds that fix the top shell to the tank bottom. This only caused weeping though and nothing more.

I used a petrol tank sealant and this worked perfectly, this lasted quite a few years to date and some sealers can be neutralised and removed at a later date, so it's not a permanent thing. POR 15 is also a good tank sealer but is only at most for pinholes, this is more permanent though.

If you have actual holes in the tank then possibly you could use steel putty to fill the hole and then seal the tank inside.

Clearly having it welded would be the best bet and a good restorer should be able to patch the tank and then grind out the welds so that the repair is mostly invisible.

[JonW]

Have a search on here, Retro in Japan remade the early ypvs tank... but its hard to get one... you will have to work to be heard etc.

[petteri]

Jul 26, 2023 8:07:29 GMT 1 JonW said:

Have a search on here, Retro in Japan remade the early ypvs tank... but its hard to get one... you will have to work to be heard etc.

Thanks for the tip, I will try to get one. That would be the number one choice and if I can get a hold of Retro Special parts then I will get one for myself atleast. 

Did you get one yourself?

[JonW]

no i didnt, i probably should have progressed it though.

Its not much of a tip sadly, no one i know has one.

What i could see was that their manufacturing was for small volumes I think and the demand was high, but that situation was fluid from what i can tell. Perhaps they outsourced it in the end or just got on and made some more?

Its worth finding out what is going on now i think.

[abar121]

Are you close to Bedford?

Kempston radiators do an excellent job of repairing / relining them.

[petteri]

Jul 27, 2023 8:51:51 GMT 1 abar121 said:

Are you close to Bedford?

Kempston radiators do an excellent job of repairing / relining them.

I live in Finland so unfortunately not.

I have a contact that lives in Japan and is willing to ship to Finland if the Retro spl has something to sell. 
Is anyone interested in a tank if I can get several pieces?
Take in to account that they would come to Finland first.

[abar121]

Sure.

I've got a 31k tank with a few small pin holes. I'm planning to solder them up and then use citric acid to remove the rust.

Degreaser, then POR tank sealer. Never tried this before.