- Thread starter VertexZ
- Start date
Yes, I'd assume all the petrol had gone. I don't have a meter and it would be too time consuming and expensive to buy one. At the end of the day, anyone has to take a view on whether all petrol vapour has been removed from the tank, whether they use water, some special gas or any other method. I'd use the heat and power of the sun over several hours - days even. There's no way there would be any petrol left in a tank after that. I don't like the idea of using water. It would just add to problems of corrosion.
In so far as it was approved (the welding of fuel tanks, that is) steam cleaning used to be the way in these islands.
I'm not sure I take the point about corrosion. If a modern tank has to be split (and some have large enough filler holes to be able to insert a dolly, or at least a dolly on a stick), then surely it would be blasted before you split it and petsealed after welding (maybe after you'd used water to check the integrity of the weld)?
I'm not sure I take the point about corrosion. If a modern tank has to be split (and some have large enough filler holes to be able to insert a dolly, or at least a dolly on a stick), then surely it would be blasted before you split it and petsealed after welding (maybe after you'd used water to check the integrity of the weld)?
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Awesome tool but unless you have one at your disposal, I think he could by 5 gas tanks for the price of that unit.
Wouldn't call myself an expert, but have repaired and modified a few petrol tanks for race/rally cars.
From all of the advice I have sort up until now the process I have used to avoid an accident so far is to give it a good steam clean to get all of the adsorbed fuel out of the cracks and metal paws, then pump exhaust gas into it. As far as exhaust goes I have only ever had petrol vehicles and had to be quick to avoid CO poisioning but really any strong flow of air/exhaust will keep any vaporising fuel at a low enough level that it will not ignite.
But if you don't feel safe, is you health worth less than the cost of a new tank?
- Dave.
From all of the advice I have sort up until now the process I have used to avoid an accident so far is to give it a good steam clean to get all of the adsorbed fuel out of the cracks and metal paws, then pump exhaust gas into it. As far as exhaust goes I have only ever had petrol vehicles and had to be quick to avoid CO poisioning but really any strong flow of air/exhaust will keep any vaporising fuel at a low enough level that it will not ignite.
But if you don't feel safe, is you health worth less than the cost of a new tank?
- Dave.
aametalmaster
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- Salem Ohio USA
Yup thats for sure but how much is loss of life worth???? Not worth doing in my mind to save a few bucks without the right equipment. Just my thinking...Bob
If you had the ability to get a heap of air out of you compressor, or it was a small tank (in which a motorbike tank might fall into this category) I would use that. As with exhaust gas is you need to keep you head as far away from the tank as possible to not breath in the fumes and rush the job, as you get sick rather quickly. It is also a good lesson in metal prep.
Breathing Argon or CO2 might be a better option, but you need the high flows to keep purging the tank of flammable gases.
- David.
Its somewhat okay to breath these gases I guess. But if you are in a confined space remember that these gases are heavier than air. Which means if there is more of this stuff than air in the area or if your welding at a bottom of a container, the gas can fill your lungs and not allow oxygen into your lungs. Resulting in being unable to breath or death. But like I say its only if you are in a contained area like a container or a partially enclosed pipe. If you are in a shop or garage and not inside something, that would be fine.
oxy
As I see it the issue is really that of preventing the (possible) remnants of petrol (or whatever) coming into contact with oxygen (and heat). Can't really weld without heat, so we can only break one side of the fire triangle by excluding oxygen (and try to get rid of as much of the fuel as possible by -- say -- steam cleaning, thus making another side weak).
To me, the worrying things about exhaust gas are that while it contains mainly CO2, it also contains O2, CO (deadly poisonous and combustible) and unburnt hydrocarbons (combustible).
If I want to put a fire out, I direct CO2 at it, if I'm welding Titanium, I immerse it in an Argon chamber.
For all that, the exhaust gas would work, I'm sure: just steam clean the tank at least twice beforehand.
To me, the worrying things about exhaust gas are that while it contains mainly CO2, it also contains O2, CO (deadly poisonous and combustible) and unburnt hydrocarbons (combustible).
If I want to put a fire out, I direct CO2 at it, if I'm welding Titanium, I immerse it in an Argon chamber.
For all that, the exhaust gas would work, I'm sure: just steam clean the tank at least twice beforehand.
The tank is off a 2000 Kawasaki KLX250 (capacity 8 litres). As mentioned motorbike parts can be hard to source second hand, and are expensive new if genuine parts (I'm guessing it would be around $AUD500 (250 pounds) for a brand new one). I know of someone who was quoted $AUD40 for a "genuine" split pin and washer for a newish Aprilia, which of course were worth around 10 cents from a hardware store!
I took the easy option and plugged the hole with metal mend about 3 weeks (metal putty) and it holds fine. I guess I will see how it holds up longer term, and should there be any issue I think I'll get a professional to weld it! Im prepared to pay someone $50 for the sake of my own personal safety, although I do appreciate all the advice you guys have given.
I took the easy option and plugged the hole with metal mend about 3 weeks (metal putty) and it holds fine. I guess I will see how it holds up longer term, and should there be any issue I think I'll get a professional to weld it! Im prepared to pay someone $50 for the sake of my own personal safety, although I do appreciate all the advice you guys have given.
Pete Hughes
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I have welded many petrol tanks in my time, Gas weld that is, I use to put a steam jenny in the filler neck and leave for as llong as poss, never failed for me, a pressure washer would poss do same thing. I have also used a kettle.
Hi I'm coming to weld a fuel tank from my car, it's not rusty but I need to cut it in half and weld it up to fit it in the boot as it keeps getting smashed on the floor in it's current location.
I've drained all fuel out, filled with soapy water and agitated and drained it twice as well as leaving the hose on it flushing it out for about 30mins.
I need to angle grind through it but obviously don't want to go up in a ball of flames, people at work told me (as well as this thread) that filling it with water than going at it is the best way but I can't see how welding a hole/gap or cutting into something with an angle grinder, that is full/pouring with water, is any safer than heating up fuel vapour? Water+welding? Water+electrical angle grinder?
I don't want to seem ghetto or like a cowboy but I just have normal DIY garage facilities, with no purging systems etc available. Does anybody have any other real world or professional/theoretical advice on how to cut and weld safely? Can I just chuck a match in the fuel tank from a distance and let it burn off, or would it explode and turn the tank into Al'Quaida-spec shrapnel?
I've drained all fuel out, filled with soapy water and agitated and drained it twice as well as leaving the hose on it flushing it out for about 30mins.
I need to angle grind through it but obviously don't want to go up in a ball of flames, people at work told me (as well as this thread) that filling it with water than going at it is the best way but I can't see how welding a hole/gap or cutting into something with an angle grinder, that is full/pouring with water, is any safer than heating up fuel vapour? Water+welding? Water+electrical angle grinder?
I don't want to seem ghetto or like a cowboy but I just have normal DIY garage facilities, with no purging systems etc available. Does anybody have any other real world or professional/theoretical advice on how to cut and weld safely? Can I just chuck a match in the fuel tank from a distance and let it burn off, or would it explode and turn the tank into Al'Quaida-spec shrapnel?
jugs
Dont wish to offend & annoy, but...
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NO Pete thats just silly, I know 2 blokes that have done that, one just lost 1 eye, 1 ear, hair and is deaf. The other lost nose lips & most of his fingers. You may have got away with it this time but before you do it again visit your local burns unit.
You may like to look at this it is film make up, but accurate.
