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[spence]

Hi all,
The petrol tank on my 500 bullet is leaking just adjacent to the support bracket above the carb. I had the bracket welded and the guy made a bit of a lash of it. Its just a weep but enough to be worried about. My question is can anyone recommend a really good tank sealant and do they actually work long term ?Any advice or comments would be helpful.
Thanks Chris

[Scalyback]

No personal experience, but I have heard good reviews of caswell's from the USA (stocked by our hosts i Think)



It's ethanol proof.



Hey Guys, DON"T put supermarket 95 octane fuel in pre 2000 bullets. Treat them to 98 or 100 octane.

[sofiaspin]

My tank developed a hairline fracture at the same point - vibration and the tank was slightly loose on the mounting bolt. If it is a similar problem just put a sealant on the outside of the tank rather than an internal sealant. You dont want leaking fuel on to the carb after stopping. It should probably be OK when running but not when it is stationary as it could lead to a fire.

[PeteF]

This is a known weak spot on these tanks. The brackets are often under tension because they don't match properly where they bolt to the frame.
It's a bit late now but perhaps a better repair would be a bronze weld on the crack and correct shimming to match the frame.
Leaking petrol is always a potential disaster and I'd be looking to get a proper repair done sooner rather than later. Perhaps the weld repair could be ground off and the job re-done with bronze.

[simon]

POR15 is a good product and they do a specific tank sealer kit. It is also quite straightforward to solder up cracks if you have a decent plumber's iron. However as pointed out already the crack is there due to tension somewhere which will need to be fixed to stop it happening again.

[spence]

Hi, thanks to all those that replied i havent been able to get to a computer to check responses. i had no idea you could solder a fuel tank im actually a plumber and reasonably good with a blow torch :-)think i might have trouble getting it to take though even with the flux it has to be pretty clean for solder to take has anyone had success soldering one of these tanks? The guy who tried to weld it before didnt use bronze and predictably blew a hole in the tank then blobed weld over it to try and fix it.I was flat out at work at the time and wish id waited and fixed it myself now.

[Norm]

Spence, Silver solder is pretty good, not 50/50 propper silver solder, I usually use 2 1/2% because that is what I have plenty of but you do need oxy to get it hot enough. Soft solder 50/50 will just crack. Make sure the tank is very well flushed before going near it with a torch but as a plumber you will be well aware of this. Silver is a bit more difficult to get to take over existing repairs that is why I usually use bronze in this situation. Take it gently and you will be fine. I fitted knee pad nuts to a tank and I had difficulty getting bronze to stop weeping, no idea why, looked a perfect weld, ran a smear of silver over the top and no problems