PETROL TANK REPAIR

[WAYNE999]

any help would be appreciated can anyone tell me the best way to make a recently used (its still got fuel in it now) safe to weld i dont fancy burning the garden fence or blowing something up

[spanners]

tank+fuel+welder ==================================BANG,,,

[WAYNE999]

tank+fuel+welder ==================================BANG,,,

I'll empty it first honest

[spanners]

petrol fume,s are worse than liquid petrol  believe me i,ve been there and done it

best to get it ,steamed out,, then fill it to the brim with water then if possible try the welder  mig may be best ,

[WAYNE999]

i dont mean to sound daft ive welded fuel tanks up before but theyve always been empty for a while

[Tony oily bike]

Not quite the same, but best read on........


http://www.mankymonkeymotors.co.uk/forum/index.php?topic=8865.0

[Manky Monkey]

BE CAREFUL!!!
I once welded a tank that'd been stood empty under a bench for several months. Didn't explode, but went with a loud POP that frightened the poop out of me.

[BikerGran]

Does it really need welding?  Couldn't you use a tak sealant inside it?

http://www.frost.co.uk/how-do-i-repair-my-fuel-tank

[big jay 257]

if it really needs welding,,, iv been told before to purge the tank with your welder gas during the process,, if using gasless exhaust gasses,, i have never tried this, but did once weld the fuel tank on my suzuki dr125 it fired a 10 foot flame from the filler a few times during welding but no harm done apart from worrying my mate lol

[ByzMax]

Empty the tank and let it air so there is no fuel in it.

Wash it out with warm soapy water and rinse blow some warm air through (hairdryer)

If your using welding gas then tap a line off and connect it to the petrol tap or the breather Depending on which way up you tank is when it's being welded.

Argon is heavier than air so to expel all the air you need the feed pipe connected at the lowest point and as it fills the tank the air gets expelled from the top. Once you have purged it start welding keeping the welding gas going in.

if your sure it's clean enough then you can do it without the gas purge. Have done it and it works 

Don't leave the tank for too long before welding after cleaning do it the same day.

Filling it with water does work but you can get steam blowing the weld as you do it.

[nabsim]

Interesting, I have always been too scared to have a go at welding a tank. Probably cos of tales down the pub in my youth about how they need steaming for at least 24 hours and can then still go bang. I would tackle said story telling mates armed with my new knowledge from this thread but unfortunately none of them have survived. Their demise was nothign to do with welding tanks, petrol or otherwise I may add

[ByzMax]

Remember it's a fuel air mixture that creates the explosion. 14 parts air to 1 part fuel is about the optimum. When in an enclosed space it'll go proper bang! 

Remove the air or the fuel and you don't have the explosion!

Saw a bloke on a video who welded a tank with loads of fuel in by just squirting a co2 fire exstinguisher down the filler cap first! 

Now don't try that at home..... Or any where else unless you want your epitaph to be a contribution to the Darwin Awards. 

[Tony oily bike]

Remember it's a fuel air mixture that creates the explosion. 14 parts air to 1 part fuel is about the optimum. When in an enclosed space it'll go proper bang! 

Remove the air or the fuel and you don't have the explosion!

Saw a bloke on a video who welded a tank with loads of fuel in by just squirting a co2 fire exstinguisher down the filler cap first! 

Now don't try that at home..... Or any where else unless you want your epitaph to be a contribution to the Darwin Awards. 

Just because it seems a good idea to begin with............

http://darwinawards.com/darwin/darwin1995-04.html