it's actually amazing how little vacuum it takes for the atmosphere to crush a steel can.
8 to 10 inches of vacuum should be enough to allow that flat long tank. I should put a gauge on one of mine, and measure how much vacuum it takes to collapse it.
heck, I ought to video the procedure...

__________________
John HAUL AWAY, OR CRUSHED CARS!!! HELP ME keep the cars out of the crusher! A/C Thread
"as I ride with my a/c on... I have fond memories of sweaty oily saturdays and spewing R12 into the air. THANKS for all you do!

My drivers:
1987 190D 2.5Turbo
1987 560SL convertible
1987 190D 2.5-5SPEED!!!

1987 300TD
2005 Dodge Sprinter 2500 158"WB
1994GMC 2500 6.5Turbo truck... I had to put the ladder somewhere!

Please do!

Take a 50 gal drum & put about 10 gal of water in it. Dont put the bung in! Put it on a fire & get the water boiling real good. Pull it out of the fire & put the bung in. Turn the garden hose on it & cool it down. It will end up as flat as a pancake.

__________________
Grumpy Old Diesel Owners Club group

I no longer question authority, I annoy authority. More effect, less effort....

1967 230-6 auto parts car. rust bucket.
1980 300D now parts car 800k miles
1984 300D 500k miles
1987 250td 160k miles English import
2001 jeep turbo diesel 130k miles
1998 jeep tdi ~ followed me home. Needs a turbo.
1968 Ford F750 truck. 6-354 diesel conversion.
Other toys ~J.D.,Cat & GM ~ mainly earth moving

I've done the test. 3 to 4" of HG is all that's needed to start collapsing a 55 gal steel drum. It's the wrong shape to withstand vacuum, flat sides, unsupported. If it was a sphere or egg shape it would withstand much higher vacuum.

__________________
85 300D turbo pristine w 157k when purchased 167,870 July 2025
83 300 D turbo 297K runs great. SOLD!
83 240D 4 spd manual- parted out then junked

Actually 2 inches ( 1 psi vac) should be more than enough to flatten a tank that size. The area of the side is ±550 inČ - that's 550 lbs pressure from both sides! I guess that you could just about do that with your mouth. Anyone like to try what they can pull on a Mitty-Vac????

__________________
Beagle

Mine was plugged up with dried mud...I think from one of those black Mud Dauber wasps. The 123 has a vacuum/pressure differential check "Check valve". Opens at pressure of 30-50 mbar and at a vacuum of 1-30 mbar in fuel tank.
I cleared mine with a compressor blow gun. I then put some screen material over it and held the screen on with a hose clamp.

Now I need to unclog my tank strainer.

__________________
Diesel-guy

want to see a really impressive imposion http://www.youtube.com/watch?v=E_hci9vrvfw

also

http://www.youtube.com/watch?v=Uy-SN5j1ogk&NR=1

__________________
hum.....
1987 300TD 311,000M Stolen. Presumed destroyed

heh, I never did that video... I may do it sometime in my spare nothing else to do time...

I now have several fuel tanks sitting around... one already collapsed that I blew back up.

__________________
John HAUL AWAY, OR CRUSHED CARS!!! HELP ME keep the cars out of the crusher! A/C Thread
"as I ride with my a/c on... I have fond memories of sweaty oily saturdays and spewing R12 into the air. THANKS for all you do!

My drivers:
1987 190D 2.5Turbo
1987 560SL convertible
1987 190D 2.5-5SPEED!!!

1987 300TD
2005 Dodge Sprinter 2500 158"WB
1994GMC 2500 6.5Turbo truck... I had to put the ladder somewhere!

I had this happen in my 1968 W110 200D... I just had the fuel tank "professionally cleaned" at a radiator shop. They were supposed to boil out the tank, but I guess all they did was put gravel in it and shake it.

After I installed the tank, I remember that every time I would open the fuel cap, I had to pull really hard on it, then suddenly it would release and I would hear a WHOOSH and popping noises from the tank as it came back to shape.

I checked the vent, and it was clogged with mud. After this point, no more problems.

I do remember that I had an issue with a clogged secondary fuel tank in a gasoline-powered 1965 International Travelall, but it would only run on that tank for about a minute before the engine would stall.

__________________
Stop paying for animal enslavement, cruelty, and slaughter. Save your health and the planet. Go vegan! I did 18 years ago. https://challenge22.com/

DON'T MESS WITH MY MERCEDES!


1967 W110 Universal Wagon, Euro, Turbo Diesel, Tail Fins, 4 Speed Manual Column Shift, A/C
1980 W116 300SD Turbo Diesel, DB479 Walnut Brown, Sunroof, Highly Optioned, 350,000+ Miles