petrol tank

[rikrobson]

Just watch this:

http://www.youtube.com/user/Davidsfarm#p/search/0/tD4KiQEnxwQ

 

[pidgeon chit welder]

Simply washing a petrol tank out with detergent and water is not good enough. Most tanks, carbs and other parts of the fuel system will have a varnish like residue coating them this can be very tough to remove, detergent will not always do it, I've even seen stuff made for removing this residue fail to shift it all. The residue when heated will give of highly flammable fumes (= good chance of explosion). I've seen and read lots of ways people have dealt with petrol tanks, and got away with it. And that is the point, they have got away with it. Using an engines exhaust to purge the tank is not safe. Using co2 is not safe (its not an inert gas). Using water is neither practical or safe. The only way that is both practical and reasonably safe is to purge with argon (or other inert gas) after washing as thoroughly as possible. I say reasonably safe, because even after taking all possible precautions, there is still the potential for explosion, so never 100% safe. Best avoided if at all possible.

You missed the live steam clean its used for road tankers that carry petrol and other flammable liquids as is also the use of co2 to build the bubbles in a strong synthetic soap foam mix ... mix till like shaving foam consistency .. same as fire brigade use to flood oil tanks to exclude air in /on the top of burning oil tanks .

High density foam made by co2 and strong synthetic liquid soap is used in industry to occupy flammable gas spaces in tanks to allow welding of the said tank whilst it still has flammable content inside , you have to have slow a continuous foam feed into the receptacle BUT it is a skilled procedure and not worth the expense of a little fuel tank.


Here is a path to the HASAW information of flammable liquids tanks

http://www.hse.gov.uk/pubns/indg314.pdf

 

[mike os]

Only done with a similar foam filled method as above

ime for stress/corrosion failures the rest of the tank is usually in almost as bad a shape. & not worth repair given the amount of work & risk

for physical damage ok, or if a replacement is not possible, but unless suitably experienced I would not attempt it

are non welded repairs MOT compliant? For metal tanks

 

[dantfer]

How old is the 7 assuming E32 as E38's have plastic tanks

I can't give any advice on welding petrol tanks as last time my advice wasn't welcome

it's actually a 95 e38 a friend of mine had the older 7 ,e32 i guess and he said his was plastic,but mine is definately powder coated steel,some of the powder coating is starting to peel off

 

[the artfull-codger]

when my old beetle tank had a small leak I took it off & cleaned up the area [empty of course] & then tinned it & soft soldered a patch on,it ran for years o-k,might even be still going now!!! as a foot note before the ''safety officers'' spell out the dangers,I used a nice large soldering iron [no dangerous flames]



slan go fol