Welding petrol tank

[Sawdoc]

I have a petrol tank with a hole in it Can anyone tell me how to make this safe to weld with out blowing myself to peices Your help would be appreciated. Cheers Tony H

[Jafa]

I have just done this on my zook tank (before it got squashed ) Obviously drain all the petrol, remove all the fittings, sender etc, fill with water, letting it overflow out all the holes for half an hour, I could still smell petrol a bit, but I waved the oxy torch at the holes and it didn't blow, so carried on. After welding up, blew it out with compressed air, left it in the sun for a couple of hours, then refitted. I also chucked in half a bottle of meths with the first tank full to a absorb any remaining moisture.

ps if it does blow, generally it just ends up like a sheetmetal ball obviously rooted, but not really life threatening, give ya a fright i would imagine!

[Sawdoc]

Sound like a good plan !
Cheers Jafa :

[Sadam_Husain]

I had one of my old 40 series fuel tanks welded up a few years back in much the same way that jaffa's outlined.

[rokhound]

Guys I have spoken too hook vehicle exhaust to a tube and let it run through the tank for about 1/2 hr (something about the carbon monoxide neutralising the fumes) . Then they do the water thing. That's what they told me when I had a new filler tube welded on anyways

[IcedJohnno]

Roks method is the better one.
Have seen a tank left under water overnight in a stream and then thankfully tested with a flaming paper on a long stick. The tank blew up big time
It would not have been pleasant to have been on the end of the gas torch.

Do the exhaust thing first

[Sawdoc]

Thanks for the extra info guys i will go with exhaust fumes method as an extra saftey measure. Keep an eye out in the deaths cololum in the press incase it doesnt work

[Jafa]

Here's a tip I learned while working in the middle east for safely welding fuel tanks on motor vehicles.

Empty a powder filled fire extinguisher into it, weld or braize it together then flush it out with water and allow to dry. Refill with petrol/deisel and away you go.

sounds like it would work too

[Dr_PC]

Wash it out then fill it wit Argon

[MAT]

Wash it out then fill it wit Argon

Yep , this is what i did when i welded my tank , washed it out with water and filled the tank with argon/co2.

[SupraSurf]

Bah just weld it up as is.. when it blows up they can actually hold together, just ends up holding about 30 litres more fuel than factory. You might have to jump on it a few times to get to fit back in tho

No matter how ready you think you are, when it goes pop you'll shit yourself

Do wot Rok and Jafa said !!!

[MAHINDRACJ4A]

hahahahahaha memories

my mahindra jeep had a few holes in the petrol tank we took it out washed it with water and drained the water out and then dad went to weld it as soon as it arc'd KABOOOM #### we got a fright the petrol tank went and hit the roof of the shed lucky dad wasn't bending over the tank other wise it would have of hit dad massive time, the tank pretty much exploded and all the edges where it was press welded/seam welded it all turned into a massive ball. never again will i weld a petrol tank

[spanky]

water then exhaust fumes is safe as ,then just wave the torch past the filler might get a small boom but safe as ,i do it all the time at work from people rooting them on the gravel roads,
vaughan

[Sawdoc]

Thanks for the feed back guys, will atempt it this weekend

[Sawdoc]

Job all done, used the water flush & exhaust fumes method and it worked a treat

[lneil]

On the same subject then, my escudo tank has taken a pounding underneath in the last couple of trips. They are small enough to begin with, now it has a capacity verging on microscopic.

Is there a feasible way of pressurising it in place to reshape it, or do I need to remove it?

Also, it has suddenly decided to not accept fuel at faster than a trickle (about 2-3 minutes per litre). From what I can gather the inlet and breather are unobstructed so could it be the dents in the bottom obstructing the fuel intake?

[Smurf]

On the same subject then, my escudo tank has taken a pounding underneath in the last couple of trips. They are small enough to begin with, now it has a capacity verging on microscopic.

Is there a feasible way of pressurising it in place to reshape it, or do I need to remove it?

Also, it has suddenly decided to not accept fuel at faster than a trickle (about 2-3 minutes per litre). From what I can gather the inlet and breather are unobstructed so could it be the dents in the bottom obstructing the fuel intake?

Shorties Pajero took a huge hit to the tank up Lake Daniels a few years ago, Jammed the tank hard up against the in tank pump so that the pump couldn't work and kept blowing fuses.
I think they just removed the sender unit on the top of the tank and pushed the tank back out with a length of 50x50 board. After towing it all the way back out to Reids Store and parking it up for a few days.

[lneil]

Cheers Smurf. I 'm just being lazy, wanting to puff it out without too much work.

[Smurf]

Is there a panel inside the back of the Scud that you can remove that allows you to get to the top of the tank/fuel lines etc, If so just remove the fuel sensor/lines etc that bolt into the top of the tank and try pushing it back into shape a bit.
I would think you could do it without removing the tank.

[pagar]

your all mad! I have welded quite a few tanks and while Filling the tank with argon or CO2 or exaust is a good start you should never run a torch over tank untill you are sure it is free of fumes, it is the fumes / vapour that goes bang not the liquid and it is posible through flushing alone that fumes will still be trapped in top of tank. I was tought to wash out tank with a consentrated solution of water and dishwash liquid as the deturgent (needs to be detergent not flowing soap as some soaps are not strong enough, as my mate found out when he lost one eye brow, about half his hair and got a very hot ear) renders petrol inflamable. then rince well with water to remove det. residue. fill with inert gas and go hard, once weldered, brased, or soldered (and cooled) rince with meths to get out any water (have used CRC in the past). out of interest a truck emptied his fuel tank down the storm water drain outside work one day after filling up with petrol instead of diesel and the firemen that attended poured deturgent down the drain so must be good.( needless to say the driver got a large fine and fired in one afternoon)