Fuel Tank Leak

[Pyro]

I've sprung a leak.

No, not me - my beautiful Shovel was weeping petrol from the near-side tank.

Took it off and no sign. So, the old trick with washing up liquid and blowing in the spigot and - hey presto - small bubbles appear just below the upper rear mounting bolt-hole. Scraped the paint off and there is an, almost invisible, hairline crack about 2mm long.

Now, this is a rare, prizewinning bike (500 made at the end of the run in 1984) and I don't want to ruin the paintjob - less still the decals which are unobtainable. So welding could be a problem.

I understand that chemical tank liners are available to seal such minor leaks - "Kreem" has been suggested. Anyone had any experience of these/have any suggestions as to a solution?

Cheers,

Pyro

PS - Now, people who know me will be a bit worried about the fact that a flammable liquid is leaking from my bike ...... please help to put their minds at rest.

[kiwidave]

I asked around as stated on the phone Tony and the word from guys who work with this stuff a lot is:


Kreem is good stuff. Preparation is everything and DON'T get it anywhere near your paint.

Also as an alternative try car parts specialists as there are epoxys for leaks on car tanks that are made for EXTERNAL application and as the leak is not ultra visible that might do you.

Give ya £3,000 for that leaky old Shovel

[kiwidave]

update from another good guy:



Sealers like Kreem and others may stop a pinhole leak, but it you've a seam coming apart, or a leak from incorrect mounting (a too-long bolt instead of a stud on the rear mount - or bolting it down with the mounts stressed) or from something rubbing on the tank that shouldn't, then sealers will be a temporary fix at best, and make the correct repair more difficult.

The correct way is to find a GOOD heliarc welder, use some heat-damming putty and localize the damage to the paint - the leak is probably in a hidden place. Then touch it up where it was fixed. The welder will know, but it's VERY IMPORTANT to purge the tank of any hint or gasoline fumes before welding.

[lawnmower]

purging petrol tanks of fumes. u need one way in one way out block all other holes and run a pipe from your exhaust pipe (or any otherexhaust) to the in holes the exhaust gases should absorb the petrol vapours and take them out the out hole. Tony dont rely on this. i did this when my yam 750 tank split in the 70's and there was no bang. let the gas run thru for at least an hour (i think)

hope this is of some help

[chilly]

Iv'e always used Biological washing powder,have had a good few tanks welded with no problems,just leave it to soak for a day,gently shaking it to stir the mix,then wash clear with water,works for me anyway.
My welder always makes me hold the tank just as a precaution for him

Petseal also do a tank liner, but this method iv'e found is a bit hit and miss and once its in there thats it no way of getting it out if you have a problem

Good luck

Chilly

[Roger]

Bıt off the wall this. Gorrilla glue from DIY shops. Its actually a wood glue but clean the tank, dampen the leak wıth water and apply Gorılla glue wıth a stıff paınt brush ınto the crack - force ıt ın. It foams up lıke bÜggery and fılls all gaps.

[Kiwi]

hairline crack

yes Kreem will stop the leak but the hairline crack will need to be addressed as cracks tend to grow

a decent welder will be able to sort the crack out without causing problems with the paintwork that can be seen

[Pyro]

Thanks Guys for all your good advice.

I'm in no hurry (still got me other bikes to ride) so I'll think on it a bit more - and maybe chat up a welder I know.

Cheers,

Pyro