Hi everyone, having a bit of an issue with my newly aquired TZR125...

I knew it had been stood for 3 years before I bought it, so I decided that before trying to fire it up I would drain the tank and clean out the carb. The carb was full of a sticky snot like substance, which I managed to eventually clean out. However the tank appears to have been filled with an epoxy tank liner at some stage which has obviously been partly dissolved by the fuel. This had also caused the gunge in the carb (as well as reed valves).

I have managed to get most of it out, but there is still one big lump still in there.

What is the best way of removing the lump? I don't want to damage the paint on the outside of the tank if I can help it, as it is pretty good.

Also even with the failed liner the tank wasn't leaking, so what are the odds of me getting away with not putting in new lining compound?

Many Thanks.

there must be a reason why it was sealed in the first place, sound like they used petseal, and TBH you would be better off shitting in the tank than using that stuff, have a look here

you can get petseal remover from here

try a few nuts and bolts in the tank first and shake around, it make come off.

if someone has gone to the trouble of sealing the tank,I would suspect it would need redoing with ethanol proof sealer.

Thanks for the help. I was thinking of getting a length of chain and inserting that into the tank. If I put nuts and bolts in there I might have a real headache getting all of them back out.

I will use a remover chamical if I have to, but that risks knackering up the paint if I spill it.

if you're really worried, why not replace the whole tank? if you need to faff about fixing this one, it might save time and money fitting a new one (doesn't even have to be a new tank)

I did consider a replacement tank, but I don't want to do that unless there is no other option.

The reason being other than the resin liner the tank is in very good condition. It is original, with no dents or major marks.

Good ones also fetch silly money. I suppose I could always sell this one on ebay, then buy another good one, but I am throwing the dice again on the replacement.

I got the petseal out of my RD400 tank without damaging the paint,

I did consider a replacement tank, but I don't want to do that unless there is no other option.

The reason being other than the resin liner the tank is in very good condition. It is original, with no dents or major marks.

Good ones also fetch silly money. I suppose I could always sell this one on ebay, then buy another good one, but I am throwing the dice again on the replacement.

The real question is why is the petseal in there?

Are you sure the tank is good?

I can't be sure the tank is good until I get the petseal out, althoyugh the paint on the tank is original and I cannot see any evidence of paint dadmage through fuel leakage.

Is it possible that there was some surface corrosion in the tank and someone added petseal to stop it blocking the fuel filter?

Short answer no.

It is not a 2minute thing to add. Takes a day or 2 to make a half decent job of it with the tank off and stripped.

Have you checked the very bottom of the tank underneath. Try to imagine where water may rest inside as modern petrol is quite wet. You end up with high concentrations of acidic water in the fuel at the very bottom if the bike stands.

That may well be where the leaky bits are. My TDR250 tank leaked there. I have treated the tank and repaired the paint.

They were only tiny pinholes.

never fixed a bike fule tank,.

but on cars we used to sand them down. to mettal around the area. then make a little plate that would cover the area. bend that to shape. "i was never very good at making them the perfect shape" clean the area nice and clean, then use solder plumbers uses for hot water pipes and melt it on to the are. sand it down a bit. then put the plate on there and then technically "but definatly not actually" weld the plate of mettal to the tank with solder around the edges.

its a bit of a pain in the butt to do. but i think thats the correct way to fix a fule tank. "if its what we had to do to cars then it should be the same for a bike right?"

you can do it with just a blow torch as well you dont need any fancy tools. but you do need to get the plate your using to match the contours very good..

having just typed all that out.

unless the hole was in a inconspicuous place on the bike tank. then it would probably stick out like a sore thumb, where as with a car the tank is hidden away. and this is probably why bikes use some sort of epoxy.

but id still probably just try to use solder without the patch rather than fill my tank with stuff that could end up in my engine..

Should be able to braise it if you have the tools for that. Pretty much the same as soldering but you get a better bond as your actualy stealing some of the existing material and mixing it with your brass as you patch the hole.

of course you have to make sure there is absolutley no fumes or fuel left in the tank before you start..

I could silver solder it at work come to think about it.

I will have a look to see where the leak is once all of this resin is out. At work I can also fill it with helium and use a Mass spectometer to "sniff" where the helium is leaking from.

just remember.. fumes + spark/flame = Boom..

you need to get all the fule/fumes out 1st.

I will make sure. I think draining it and leaving it in a warm place for a few days should do the trick.

I will make sure. I think draining it and leaving it in a warm place for a few days should do the trick.

warm place wont make much difference for petrol, well ventilated is better to think of