Repairing dents in fuel tanks

[koolio]

I have a large dent in the side of my tank and a couple of small dents as if someone tried to knock a hole with a small hammer.

I think this is beyond me for a repair but I was wondering whether or not his is a big deal/expensive thing to deal with? I'm not worried about damaging the paint.

Can any bodyshop deal with this?

[Robby]

A bodyshop can, but its worth having a go yourself.

A bit of health and safety first, that it actually is worth following this time. Before trying anything, make sure the tank is drained of fuel and has been standing empty in an airing cupboard or something for a fuel days, so not even vapours remain. These methods could create a spark.

That said, I have had great fun by playing fuel tank ramjet, waving a match in front of a tank with some vapour left in it. Burns hot and fast, leaves a mark on your hand akin to putting it on a hot frying pan for a second.

2 methods.

1. Traditional - pop it out. Using a bar, find some leverage behind the dent, and apply consistent pressure until it pops out. You may need a selection of bent bars to get the leverage.

2. Might not work. The hot/cold method. Warm the area around the dent with a hairdryer for a few minutes, then spray the dent itself with a can of CO2 (keyboard cleaner) held upside down. The theory is that the sudden change in temperature pulls it taught and pops the dent out. Didn't work for me, even when I tried a blowtorch and freeze and release.

Some people will suggest methods like pressurising it with water, or filling it with water and freezing it so the ice pushes the dent out. This is quite likely to leave you with a split tank at worst, and a rusty tank at best. I detest rusty tanks, having dealt with several of them in my time.

[recman]

Can you post a picture of the dent and the location relative to the filler hole?
It could be that the metal has stretched slightly which does pose a problem sometimes.
If this is the case, it may well be worth your while filling the sharper dents rather than lifting them out because by the time you've finished, the metal will be paper thin or it may even have split.

[Vincent]

Aye, I'd go the filler route too. Just means you'll get a few miles less out of a full tank.
____________________
Space Is Deep

[koolio]

Thanks everyone, I don't have the bike with me at the moment, the largest dent is square on the side of the tank doesn't look deep but its certainly wide the other two are little dings (both are no where near the filler cap), there's a body shop down the road I think I'll try them first, I would like the extra mileage back!

[Casper]

If the bike is comman like a bandit you might find another tank cheaper than filler, paint, time and energy.

[Vincent]

[doggone]

You could try the tapping out any dents - 'PDR' .
I was just watching this guy's youtube video for example.
https://www.motorcycledentremoval.co.uk/contact.html
Probably all to easy to make it worse trying yourself.

I think I would rather try this than mucking about with filler, depends how smart the bike is.

[stinkwheel]

Is the metal creased?

If not, applying heat then cold spray is like black magic.

Have a search on youtube for hot cold dent removal.

They all use upside down air dusters for the cold spray but that's because they are apparently unaware of the existance of plumbers freeze spray.
____________________
“Rule one: Always stick around for one more drink. That's when things happen. That's when you find out everything you want to know.”
I did the 2010 Round Britain Rally on my 350 Bullet. 89 landmarks, 3 months, 9,500 miles.

[sickpup]

[karthead]

There's a method for repairing dinted expansion chambers but I don't know if you'd get any luck with it for your fuel tank. They plug one end of the exhaust, fill the exhaust with water completely, plug the other end, freeze the exhaust and the water expands as it freezes, pushing the dints out. Don't go doing it without a more knowledgeable person saying it's ok, though

Just something for you to consider. Good luck.

[nowhere.elysium]

[karthead]

[karthead]

After a bit of reading, you're not supposed to plug both ends, and don't top it fully with water. On another forum a guy said he plugged both ends, the expansion chamber split when he found it in the freezer next morning!
I'll leave it up to experts like nowhere.esylium to tell you what/not to do (I never said to do it, i thought it was worth mentioning in order to get clarification)

[Chalky.]

It's better to give no advice than bad advice.

[nowhere.elysium]

[_Iain_]

[karthead]

[dogwafter]

I remember hearing one from a guy, get an old truck inner-tube and put it in your tank and over inflate it.

[gandy666]

use filler and spray cans mate..

easiest and cheapest method and you can get a good finish

most haynes manual have a section on how to fill, prime and paint, or there used to be a section on the halfords website somewhere..

its pretty straight forward. hardest thing is finding somewhere wind free to respray it with the cans.

is it metallic or straight colour?

remember and use petrol proof lacquer

[Drake]

[The Artist]

Propane + air + ignition = rapid expansion of gases.

Put some propane in your fuel tank and light it, sorted.