I need to make sure it won't explode and was thinking about letting it
sit in the sun open for a few days then fill it completely with water.

Any other ideas?

"Modat22" wrote in message
...
I need to make sure it won't explode and was thinking about letting it
sit in the sun open for a few days then fill it completely with water.

Any other ideas?

Let it completely dry out. Flush a couple of times. Empty and let dry.
Flood with Argon, as it won't mess up the weld like water will from the back
side.

Steve

I was going to weld up my gas tank in my car .I took the tank out got
the gas out filled it with water.
Drained the water and I still smelled a little gas ,filled it again
with water and let it sit overnight.Drained the water still had a
slight smell of gas, I filled it and drained it many more times .
Before I welded it I rolled up a newspaper stuck it in the tank and lit
the other end a ran back BOOM , the tank was now round.

Modat22 wrote:
I need to make sure it won't explode and was thinking about letting it
sit in the sun open for a few days then fill it completely with water.

Any other ideas?

I flush fuel tanks our with hot water and dishsoap. Hit it with the soap
& water twice, shake hell out of it each time and be sure you get lots
of suds with each rinse. You can fill it with CO2 if you're feeling
squeamish, being on the safe side is a Good Thing.

John

"JohnM" (clip) You can fill it with CO2 if you're feeling squeamish, being
on the safe side is a Good Thing.
^^^^^^^^^^^^^^^^
No matter how many times you rinse it, or how long you let it stand empty
with the cap off, it is NEVER safe to assume that all the gas is gone. It
creeps into the seams, and then comes out as vapor when the welding heat
reaches it.

I once had to weld up some cracks around the fuel valve on the bottom of a
Harley tank. I filled the tank with water, put the cap on, and turned the
tank over. I thought I was doing fine, but this is what took place: A
little stream of water was coming out the vent hole in the cap, so the water
level dropped very slowly. Gasoline inside the tank (there must have been a
little left) floated to the surface of the water. The welding heat set it
off, and it exploded, blowing the cap off. A solid column of water came
out, hit the bench, and got me and everything wet. I am not religious, but
I took this a message not to do it this way.

I have heard of a welding shop which runs the exhaust from a small engine
into the tank for an hour or so, and then welds. They're still in business,
so I guess this is safe.

Modat22 wrote:

I need to make sure it won't explode and was thinking about letting it
sit in the sun open for a few days then fill it completely with water.

Any other ideas?

I believe that radiator shops can soak the gas out (dunno how, saw it
here I think). I _do_ know that if you take it to a professional paint
stripper there won't be any gas left in it (or paint on it for that
matter) when they're done. If you're fixing rust problems this might be
the way to go.

I've only worked on one tank, we had it professionally stripped.
Nothing exciting happened.

--

Tim Wescott
Wescott Design Services
http://www.wescottdesign.com

Modat22 wrote:
I need to make sure it won't explode and was thinking about letting
it sit in the sun open for a few days then fill it completely with
water.

Any other ideas?

Use epoxy.

What would happen if you pulled a vacuum on the tank? Would that get all
the gas vapor out like it was water vapor coming out of a Freon system?

"Chief McGee" wrote in message
news:566Me.271648$xm3.181044@attbi_s21...
What would happen if you pulled a vacuum on the tank? Would that get all
the gas vapor out like it was water vapor coming out of a Freon system?

You'd collapse the tank. THUNK!

LLoyd

I've done a few and my usual method is to first rinse with water then
attach a shop vac to the gas fill opening (using the handyman's secret
weapon). Have the vac running while welding. The first time I tried
this I remotely started the vac to be sure fumes would not ignite in
the vac.

Modat22 wrote:
I need to make sure it won't explode and was thinking about letting it
sit in the sun open for a few days then fill it completely with water.

Any other ideas?

Modat22 wrote:

I need to make sure it won't explode and was thinking about letting it
sit in the sun open for a few days then fill it completely with water.

Any other ideas?

It's been years and years, but I remember using the butt end of an Electrolux
vacuum cleaner to blow air into a tank (previously emptied as empty as I could
get it) for about 24 hours. If the tank is sloshable you can try a much less
flammable solvent like paint thinner, which should still dissolve the gasoline,
and then blow *that* out.

GWE

Seal-All from a auto parts store...MAGIC!!!


"Modat22" wrote in message
...
I need to make sure it won't explode and was thinking about letting it
sit in the sun open for a few days then fill it completely with water.

Any other ideas?

OK, but other than that minor detail, would it work?


"Lloyd E. Sponenburgh" wrote in message
. ..

"Chief McGee" wrote in message
news:566Me.271648$xm3.181044@attbi_s21...
What would happen if you pulled a vacuum on the tank? Would that get
all
the gas vapor out like it was water vapor coming out of a Freon system?

You'd collapse the tank. THUNK!

LLoyd

"Modat22" wrote in message
...
I need to make sure it won't explode and was thinking about letting it
sit in the sun open for a few days then fill it completely with water.

Any other ideas?

The way that fuel tankers are degassed is to wash the interiors
with hot (+70C) soapy water, then rinse out all suds etc.
Put a steam hose inside each compartment and steam the interiors
for at least 30 minutes. Let the tanker cool, then get a hydrocarbon
gas detector and check for any vapours. The testing has to show
less than 10% of the lower explosive limit for the last product
carried - eg petrol 1.3% LEL has to show 0.13% or less on the
gas detector. If you get that result then work can start straight
away. If the tanker is not worked on for 2 or more hours it has
to be retested before work can start.

Most metals and alloys will absorb petroleum products, and with
heating will release vapours which can ignite and under the right
air/vapour mix will explode. The addition of various anti knock
compounds to unleaded fuel makes it even harder to degas a tank
as they form a gum like layer if just steamed - hence the hot water
wash.

I know the above seems a lot to do for a small fuel tank, but every
so often I see reports of some poor sod who has lost his life by
welding/grinding/drilling into a fuel tank or more often a 205 litre
drum. The combustible liquids - oils, diesel, grease, detergents even
seem to present a greater danger as people do not recognise those
products as being dangerous when heated above their ignition
temperatures. Most people tend to take care with petrol and at least
do a basic degas.

Modat22 wrote in
:

I need to make sure it won't explode and was thinking about letting it
sit in the sun open for a few days then fill it completely with water.

Any other ideas?


My old welding instructor favored running a hose from a vehicle's tailpipe
into the tank and letting the vehicle's engine idle for a while before
starting to weld and continuing to run while the welding was being
performed.

This provided a CO2/CO purge of the tank with an inert atmosphere inside
the tank during the welding process.

He also used this technique when using an OA torch on old oil drums.

You got allot of anwers here. Most of em won't kill you, but some won't get
yery good results. Oxygen in water will combine with iron to make iron oxide
(rust/slag) and you won't get a very good weld

Gas can't combust if there's no free oxygen present, so flooding with inert
gas is the safest. Argon will work, but you have to make sure you have a
good flow (positive pressure) of argon in the tank all the while you are
welding. Even so, Argon (atomic weight 18) is heavier than air, mostly
nitrogen (A.W. 7), and oxygen (A.W. 8). If you're working on an area at the
highest point of the tank, there may be a bubble of trapped air behind it.
If the welding is to be done on a boss or fitting, you can open (or remove
what ever is in it) and let the gas flow out.

Probably the safest would be helium. It's definitly light enough to
accumulate at the high spot, and displace the air. And this is usually the
position you want to weld in.

Be careful


Mark


"Modat22" wrote in message
...
I need to make sure it won't explode and was thinking about letting it
sit in the sun open for a few days then fill it completely with water.

Any other ideas?

On Mon, 15 Aug 2005 19:56:51 GMT, "Tom Gardner"
wrote:

Seal-All from a auto parts store...MAGIC!!!

Agreed!!


"Modat22" wrote in message
.. .
I need to make sure it won't explode and was thinking about letting it
sit in the sun open for a few days then fill it completely with water.

Any other ideas?


Wayne Cook
Shamrock, TX
http://members.dslextreme.com/users/waynecook/index.htm

"Wayne Cook" wrote in message
...
On Mon, 15 Aug 2005 19:56:51 GMT, "Tom Gardner"
wrote:

Seal-All from a auto parts store...MAGIC!!!

Agreed!!

There are only a few MAGIC things out there, Kroil is another.

On Tue, 16 Aug 2005 01:25:04 GMT, "Tom Gardner"
wrote:


"Wayne Cook" wrote in message
.. .
On Mon, 15 Aug 2005 19:56:51 GMT, "Tom Gardner"
wrote:

Seal-All from a auto parts store...MAGIC!!!

Agreed!!

There are only a few MAGIC things out there, Kroil is another.

And the seal all is not a permanent repair. After about 3 years you
get to do it over.
I wash them out with HOT water, then shoot a CO2 extinguisher into the
tank before welding. Ore use the inert gas from your Mig/Tig welder.

We used to weld and braze the old Harley and Indian tanks by blowing them
out good with the air hose, securing one of the brackets in the vise, and
"popping" the remaining vapor with the torch at the cap hole. They were
plenty strong enough to contain that with the cap off. A larger and/or
thinner tank would be a whole different situation. I now am somewhat smarter
and am not recommending this procedure!!!
Don Young

"Leo Lichtman" wrote in message
...

"JohnM" (clip) You can fill it with CO2 if you're feeling squeamish,
being on the safe side is a Good Thing.
^^^^^^^^^^^^^^^^
No matter how many times you rinse it, or how long you let it stand empty
with the cap off, it is NEVER safe to assume that all the gas is gone. It
creeps into the seams, and then comes out as vapor when the welding heat
reaches it.

I once had to weld up some cracks around the fuel valve on the bottom of a
Harley tank. I filled the tank with water, put the cap on, and turned the
tank over. I thought I was doing fine, but this is what took place: A
little stream of water was coming out the vent hole in the cap, so the
water level dropped very slowly. Gasoline inside the tank (there must
have been a little left) floated to the surface of the water. The welding
heat set it off, and it exploded, blowing the cap off. A solid column of
water came out, hit the bench, and got me and everything wet. I am not
religious, but I took this a message not to do it this way.

I have heard of a welding shop which runs the exhaust from a small engine
into the tank for an hour or so, and then welds. They're still in
business, so I guess this is safe.

"Chief McGee" wrote in
news:XW7Me.272139$xm3.99251@attbi_s21:

OK, but other than that minor detail, would it work?

No. There would still be Oxygen and fumes in the tank. Plus you'd be
sucking the welding sparks right into the tank.



"Lloyd E. Sponenburgh" wrote in
message . ..

"Chief McGee" wrote in message
news:566Me.271648$xm3.181044@attbi_s21...
What would happen if you pulled a vacuum on the tank? Would that
get
all
the gas vapor out like it was water vapor coming out of a Freon
system?

You'd collapse the tank. THUNK!

LLoyd







--

Dan

"Modat22" wrote in message
...
I need to make sure it won't explode and was thinking about letting it
sit in the sun open for a few days then fill it completely with water.

Any other ideas?


The way I do them is real simple. Drain tank of fuel. Dump in a couple
gallons of alcohol, slosh that around real well. Now put in 1/4 tank of
HOT water with some Simple Green in it (lowers the surface tension so it
gets into the tighter areas easier) Then dump it out. Then I connect up
the exhaust from a good running 4 stroke (no oil burners or two strokes,
oil fumes may ignite.) and let it fume for 1/2 hour or so. Now you can
braze or weld without problems. Filling with water makes it hard to do
work on the tank because it acts as a heat sink.
Done 30 or more and still have all my fingers, toes and hair....

Steve W.



----== Posted via Newsfeeds.Com - Unlimited-Uncensored-Secure Usenet News==----
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On Mon, 15 Aug 2005 23:15:10 GMT, "MM" wrote:

,;
,;You got allot of anwers here. Most of em won't kill you, but some won't get
,;yery good results. Oxygen in water will combine with iron to make iron oxide
,;(rust/slag) and you won't get a very good weld
,;
,;Gas can't combust if there's no free oxygen present, so flooding with inert
,;gas is the safest. Argon will work, but you have to make sure you have a
,;good flow (positive pressure) of argon in the tank all the while you are
,;welding. Even so, Argon (atomic weight 18) is heavier than air, mostly
,;nitrogen (A.W. 7), and oxygen (A.W. 8). If you're working on an area at the
,;highest point of the tank, there may be a bubble of trapped air behind it.
,;If the welding is to be done on a boss or fitting, you can open (or remove
,;what ever is in it) and let the gas flow out.

Argon is a heavier molecule but your data is wrong. You have given the
atomic numbers for those gases not the molecular weights. The
approximate molecular weights are Ar=40, O2=32, and N2= 28. Note that
both oxygen and nitrogen are diatomic gasses. (Two atoms per
molecule.)

I would fill the tank completely with water and then dry with a argon
purge and weld while the argon is flowing.

You also can buy a plastic which will form a polymer coating inside
the tank. If you have a rust hole this would be a better choice as it
will seal the holes which will show up next week after you finish
welding and put the tank back.
,;
,;Probably the safest would be helium. It's definitly light enough to
,;accumulate at the high spot, and displace the air. And this is usually the
,;position you want to weld in.
,;
,;Be careful
,;
,;
,;Mark
,;
,;
,;"Modat22" wrote in message
...
,; I need to make sure it won't explode and was thinking about letting it
,; sit in the sun open for a few days then fill it completely with water.
,;
,; Any other ideas?
,;

On Mon, 15 Aug 2005 21:49:43 GMT, the opaque "Roger & Lorraine Martin"
clearly wrote:

temperatures. Most people tend to take care with petrol and at least
do a basic degas.

Erm, Degas...wasn't he a painter?


the tank, I'd go with an off-the-shelf cleaner/degreaser
+ liquid liner package.

These guys do it right. I wonder what that costs in Canuckistani
ducats. http://www.leakersgastanks.com/


---=====---
After all else fails, read the instructions.
---=====---
Website Design and Update http://www.diversify.com

On Mon, 15 Aug 2005 21:42:33 -0400,
wrote:

On Tue, 16 Aug 2005 01:25:04 GMT, "Tom Gardner"
wrote:


"Wayne Cook" wrote in message
. ..
On Mon, 15 Aug 2005 19:56:51 GMT, "Tom Gardner"
wrote:

Seal-All from a auto parts store...MAGIC!!!

Agreed!!

There are only a few MAGIC things out there, Kroil is another.

And the seal all is not a permanent repair. After about 3 years you
get to do it over.
I wash them out with HOT water, then shoot a CO2 extinguisher into the
tank before welding. Ore use the inert gas from your Mig/Tig welder.

Hmm. It may not be permanent but it's darn sure better than that. I
guess in some situations it might only last that long. Let's see. I
think it's been on the gas tank of my lawn mower for 12-15 years now.
It was on the radiator of my Toyota for 5 years before I had to redo
it.

Of course I'm not saying that welding isn't needed on gas tanks. I
do it when I have to. But for many things Seal All will work and do a
good job.

As far as the way to weld on gas tanks. Well get all the gas you can
out with what ever method works for that particular tank and what
you've got available. Many methods have been posted so far. Then purge
the tank with some form of inert gas. I use CO2 myself.

Wayne Cook
Shamrock, TX
http://members.dslextreme.com/users/waynecook/index.htm

Steve W. wrote:
"Modat22" wrote in message
...

I need to make sure it won't explode and was thinking about letting it
sit in the sun open for a few days then fill it completely with water.

Any other ideas?



The way I do them is real simple. Drain tank of fuel. Dump in a couple
gallons of alcohol, slosh that around real well. Now put in 1/4 tank of
HOT water with some Simple Green in it (lowers the surface tension so it
gets into the tighter areas easier) Then dump it out. Then I connect up
the exhaust from a good running 4 stroke (no oil burners or two strokes,
oil fumes may ignite.) and let it fume for 1/2 hour or so. Now you can
braze or weld without problems. Filling with water makes it hard to do
work on the tank because it acts as a heat sink.
Done 30 or more and still have all my fingers, toes and hair....

Steve W.



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http://www.newsfeeds.com The #1 Newsgroup Service in the World! 120,000+ Newsgroups
----= East and West-Coast Server Farms - Total Privacy via Encryption =----

I used to watch snowmobile "techs" dump out the gas from the tank of a
Ski Doo by turning it over..... then they would turn it right side up
and pass a torch over the filler neck....... VA-WOOOM.!!!!!! there would
be a large flaxh from the filler neck and the resultant downward force
from the blast would compress the springs on the front skis and then the
whole machine would jump into the air when the spring would
return....... they would repeat this a couple of times until the filler
neck produced no more flashes!!! Must have been the cold air
protecting them (grin)
Pat

--
Email: patlandy_at_verizon.net
HELP GROW THE ECONOMY, SUPPORT THE FAIRTAX.
http://fairtax.org

I need to make sure it won't explode and was thinking about letting it
sit in the sun open for a few days then fill it completely with water.

Any other ideas?
I've used the exhaust port from a shop vacuum piped into the tank and
just let the vacuum run until you're done welding. Moves enough air
that there is no build-up of fumes..... I've also used water on
smaller lawn mower type tanks.
Ken.

We've also use the exhaust from a portable generator =)


Ken Sterling (Ken Sterling) wrote in message
...
I need to make sure it won't explode and was thinking about letting it
sit in the sun open for a few days then fill it completely with water.

Any other ideas?
I've used the exhaust port from a shop vacuum piped into the tank and
just let the vacuum run until you're done welding. Moves enough air
that there is no build-up of fumes..... I've also used water on
smaller lawn mower type tanks.
Ken.

In article SJPOe.1366$N22.1122@trndny07,
"Jon Grimm" wrote:

We've also use the exhaust from a portable generator =)


Ken Sterling (Ken Sterling) wrote in message
...
I need to make sure it won't explode and was thinking about letting it
sit in the sun open for a few days then fill it completely with water.

Any other ideas?
I've used the exhaust port from a shop vacuum piped into the tank and
just let the vacuum run until you're done welding. Moves enough air
that there is no build-up of fumes..... I've also used water on
smaller lawn mower type tanks.

My father welded many truck fuel tanks; he filled them completely full
and had an assistant with a fire extinguisher put out the inevitable
fire. Never an explosion.

--
Free men own guns, slaves don't
www.geocities.com/CapitolHill/5357/

Nick Hull wrote:

In article SJPOe.1366$N22.1122@trndny07,
"Jon Grimm" wrote:


We've also use the exhaust from a portable generator =)


Ken Sterling (Ken Sterling) wrote in message
...

I need to make sure it won't explode and was thinking about letting it
sit in the sun open for a few days then fill it completely with water.

Any other ideas?

I've used the exhaust port from a shop vacuum piped into the tank and
just let the vacuum run until you're done welding. Moves enough air
that there is no build-up of fumes..... I've also used water on
smaller lawn mower type tanks.


My father welded many truck fuel tanks; he filled them completely full
and had an assistant with a fire extinguisher put out the inevitable
fire. Never an explosion.

Full of what? Please don't say gasoline...

Jim Stewart wrote:
Nick Hull wrote:

In article SJPOe.1366$N22.1122@trndny07,
"Jon Grimm" wrote:


We've also use the exhaust from a portable generator =)


Ken Sterling (Ken Sterling) wrote in message
...

I need to make sure it won't explode and was thinking about
letting it sit in the sun open for a few days then fill it
completely with water. Any other ideas?

I've used the exhaust port from a shop vacuum piped into the tank
and just let the vacuum run until you're done welding. Moves
enough air that there is no build-up of fumes..... I've also used
water on smaller lawn mower type tanks.


My father welded many truck fuel tanks; he filled them completely
full and had an assistant with a fire extinguisher put out the
inevitable fire. Never an explosion.

Full of what? Please don't say gasoline...

I suspect that is what it was.
I have seen it done - welding on a full gas tank.
as was said - with a TRUSTED assistant standing by with a fire extinguisher
to put out the flaming welder.

Ken.

"Ken Davey" wrote in message
...
Jim Stewart wrote:
Nick Hull wrote:

In article SJPOe.1366$N22.1122@trndny07,
"Jon Grimm" wrote:


We've also use the exhaust from a portable generator =)


Ken Sterling (Ken Sterling) wrote in message
...

I need to make sure it won't explode and was thinking about
letting it sit in the sun open for a few days then fill it
completely with water. Any other ideas?

I've used the exhaust port from a shop vacuum piped into the tank
and just let the vacuum run until you're done welding. Moves
enough air that there is no build-up of fumes..... I've also used
water on smaller lawn mower type tanks.


My father welded many truck fuel tanks; he filled them completely
full and had an assistant with a fire extinguisher put out the
inevitable fire. Never an explosion.

Full of what? Please don't say gasoline...

I suspect that is what it was.
I have seen it done - welding on a full gas tank.
as was said - with a TRUSTED assistant standing by with a fire
extinguisher to put out the flaming welder.

Ken.

Three systems, and I've seen them all work:
1 - empty tank as much as possible, run exhaust gas (just the gas, not the
heat) from a vehicle into it, and allow the exhaust gas to displace the
volatile vapors.
2 - Completely fill the tank with water and weld it
3 - completely fill the tank with gasoline and weld it
The whole idea is to avoid flash point of the volatile vapors. On a side
note, when I was young and stupid (instead of being old and stupid), I cut
the gas tank hanger straps off a 1939 Ford Coupe which was upside down in a
field. There had been no fresh gasoline in that tank for 18 years, and,
luckily for me, the gout of flame went between my legs and 20 feet into a
field, which promptly caught fire. Be careful!!!



--
Peter DiVergilio
Most of the money I've wasted was mostly spent trying to impress people who
were never going to like me anyway!

In article ,
"Peter DiVergilio" wrote:

Three systems, and I've seen them all work:
1 - empty tank as much as possible, run exhaust gas (just the gas, not the
heat) from a vehicle into it, and allow the exhaust gas to displace the
volatile vapors.
2 - Completely fill the tank with water and weld it
3 - completely fill the tank with gasoline and weld it

3a - Completely fill the gasoline tank with kerosine. Less flame, less
volitile, and after you empty it a bit of kero doesn't bother the
gasoline.

The whole idea is to avoid flash point of the volatile vapors. On a side
note, when I was young and stupid (instead of being old and stupid), I cut
the gas tank hanger straps off a 1939 Ford Coupe which was upside down in a
field. There had been no fresh gasoline in that tank for 18 years, and,
luckily for me, the gout of flame went between my legs and 20 feet into a
field, which promptly caught fire. Be careful!!!

--
Free men own guns, slaves don't
www.geocities.com/CapitolHill/5357/