Re: Welding near the lpg and petrol filler

How about just draining the tank and leaving it to vent (drain plug out and filler cap off) for a couple of days - its the fumes that's the really explosive stuff. Alternatively you could drain it and then blow through with an air line?

Geoff

On or around Tue, 5 Aug 2003 07:18:25 +0000 (UTC), Terry Lyne enlightened us thusly:

looking at it another way, don't release gas anywhere near the pit.

Mind you, I was welding the chassis right beside my LPG tank the other day, and it didn't blow up. Admittedly, not near the filler. The only way you get gas in the vicinity is via a leak. The tank and all lines are sealed. you should exercise care in welding near to flexible filler hoses, which being rubbery stuff can get burnt, so moving 'em out of the way would be good. The filler hose should be sealed at both ends, by a valve on the tank and a valve in the filler, so a flexible filler hose should only release the gas in the hose itself if you undo it.

in still or slow-moving air, LPG will sink to the floor and run downhill, hence not venting it near your pit.

finally, don't use a vacuum cleaner to remove flammable fumes...

Oo-er missus. Don't do this! Petrol fumes will hang around for ever. Leaving it to evaporate in the way you describe is not an option, and even blowing it through is useless. ISTR the "official" method if a fuel tank needed welding was to pass steam through it under pressure for at least two hours, or to fill with water and detergent and leave for a few days before draining. Empty fuel tanks are about the most dangerous thing in the automotive world. You would probably be safer welding near a full one.

Personally I wouldn't weld anywhere near a fuel tank. I would drop it out and store it somewhere in the next county before I even got the welding gear out.

I've no doubt that people do weld near to fuel tanks and the like, but not when I am around. Just imagine the consequences if you got it wrong...

DaveP

I agree with Dave! I was involved in an experiment whereby we filled a plastic 2 litre milk container with petrol, wrapped it in a belt of cortex and set it off with a detonator. Rather than burning the petrol basically detonated... Not an exact comparison with your welding problem but similar enough to make me very wary of getting sparks or heat near petrol!

Please would you advise which county you intend to weld in, so that I can go on holiday that day if need be.

Cheers,

M.

If you

On or around Tue, 05 Aug 2003 16:31:24 GMT, snipped-for-privacy@dev.nul (QrizB) enlightened us thusly:

It won't blow up if it's *full* of water. however, most people don't want water in their fuel tank - not a problem in the case quoted.

Where abouts you be in devon my luverly (spent 4 years living in Newton Abbot)

The range rover repair manual as published by landrover states that to weld a tank is dodgy, but should it be neccessary, first steam it for 2 hours. Sounded more like a recipe to make Xmas pud if you ask me.

I did once try repairing a tank once. I dropped it, drained and it stood outside for 5 days. It didn't explode, but the flame out of the filler cap would have made Arthur Whittle extremely jealous, especially as it moved across the floor at what seemd like Mach3 at the time! After that little episode, I decided I would never repair another tank, no matter how small or insignificant the hole or leak..... Cheaper for a new tank than new limbs.

Interestingly enough, the Army, Navy and RAF claim that you can use Avtur (jet fuel) to extinguish a fire if it is in liquid form, its only a problem if its a vapour. The yanks also spray petrol onto fires made of cotton bales as it is the only substance which will penetrate to the middle of the fire, where the absence of fumes renders it inert hence extinguishing the fire.......

-- Simon Isaacs

Peterborough 4x4 Club Chairman and Webmaster

I'm about 6 miles from Newton Abbot so they should be safe there:-)

In the past I've set fire mainly to carpets, bitumen paint and through chassis wiring looms on Series Land Rovers :-))

A petrol tank would be The BIGGY??

Nah - think I'll drop the fuel tank out before I weld the new floor panel to the new wheel arch

On or around Tue, 5 Aug 2003 23:41:29 +0100, "Graeme" enlightened us thusly:

RR tank is not that bad to get out, provided as you say the captive nuts behave. I have to admit, when I dropped the one on the 110 I wasn't intending to replace it.

On or around Tue, 5 Aug 2003 23:03:45 +0000 (UTC), "Simon Isaacs" enlightened us thusly:

I did similar, but washed it out with soapy water. Didn't ignite.

small holes can be repaired with epoxy glue (Araldite, JB Weld, etc)

Haven't got a clue - (I live near Stokeinteignhead on the far side of Newton Abbot from Seale Hayne and I get over that way once in a blue moon)

Right - must get out in the sunshine and weld (well clutch first methinks)

On Wed, 6 Aug 2003 21:07:38 +0100, "Graeme" made me spill my meths by writing:

Likewise here, I had hoped both tanks would be OK but in the event, one of them didn't like being removed at all and was binned. The outrigger had seen better days as well. I might have got another few years out of both but the disturbance at the time was what finished them off. Unless you are prepared to fork out for at least one tank (the outriggers aren't too expensive at all) then maybe best left alone.

There is a bolt to get to at the rear most outrigger that, if old and covered in crud, is an absolute nightmare. Definite candidate for a lifetimes covering of grease or whatever to keep the corrosion away.

As for welding in the vicinity, apart from the possibility of fumes, you should be alright with some shielding. Beware the fuel lines though, weld spatters won't agree one bit with them. Welding on the passenger door pillar might be a bit close to the carb as well.

I had someone with me with a water squirter when I was welding in harder to get areas. Sometimes he saw my overalls smoking, other times I had to scream loudly and try to run away from the hot bits, not easy when they have already made it through the first few layers.

All the best