Best way to remove tank valve?

[cappyjon431]

When I bought our dive op it came with 70 tanks, about a dozen of which had valves that needed repair/replacement. They have sat under my work bench for years, but I finally decided to replace the valves. It looks like these tanks had never been rinsed and after draining, the vaves are seriously hard to remove. I tried to loosen them up with a soft mallet, with no success. I put a pipe wrench on one an succeeded in removing the valve by tapping the pipe wrench with the soft mallet but scraped up the valve in the process. I would like to rebuild these valves, but I don't want to damage them in the removal process. What is the best way to get these buggars off? Thanks for any input.

 

[Scared Silly]

Put your pipe wrench on and use a cheater bar instead of the mallet.

 

[Belmont]

Put a piece of neoprene between the jaws of the pipe wrench, cheater bar is good but a few sharp blows with a hammer on the bar will help break the seal.

 

[Scott]

Use a smooth jaw wrench and it won't leave the marks like a typical pipe wrench.
Smooth Jaw Wrenches

 

[cbrich]

I would use an open end wrench that would fit the flats on the base of the valve, assuming the valve has flats on the base. But it sounds like you might be replacing all of the valves.

 

[Mark Michaud SELAUSAR]

If it is possible, put the valves (and tanks) in warm water for a while. This may loosen the scale that has built up.

 

[Colliam7]

I would like to rebuild these valves, but I don't want to damage them in the removal process. What is the best way to get these buggars off?

Put a piece of neoprene between the jaws of the pipe wrench, cheater bar is good...

Use a smooth jaw wrench and it won't leave the marks like a typical pipe wrench.

Other alternatives would include: a) use two pieces/strips of smooth (and softer) aluminum, instead of neoprene, between the jaws of the wrench and the valve, or b) use hard wood (oak) strips. Possibly less expensive alternatives to a new wrench. We keep aluminum shims in our bench vise at the shop for a similar purpose. And, Zeagle markets a wood box to support applying torque to regulators, with the same end in mind - avoiding scratching the metal. With the wrench, while I use a rubber mallet at times, my personal preference is a cheater bar if I can effectively secure the tank so it doesn't rotate.

 

[NJDiver07866]

Don't sound like a drama queen, and you might have already thought of this, but just to be safe make sure the valve works. Take a bit of shop air and open up the valve and try to fill the tank. Check to see air goes in and out of the tank through the open valve. With old tanks you always have to be careful they are indeed empty. It could be the valve is bad and you think the tank is empty when it is really not. You can turn the valve open with the knob and it feels like it’s open but it’s not. So before you try to put an 8 foot breaker bar on it.. just do a quick check…

Good luck my friend

 

[rcs9250]

For tough valves on SCBA's and some scuba tanks I made a wrench as pictured. I work in a machine shop so it was a real quick and dirty job. Sometimes making the tank immobile is a tougher task. A tank vise of course works well. I have seen people jack up a trailer with tandem axles and lower it slightly on the tank to act as a vise. Some have strapped them to I beams and telephone poles too.

 

[cappyjon431]

Don't sound like a drama queen, and you might have already thought of this, but just to be safe make sure the valve works. Take a bit of shop air and open up the valve and try to fill the tank. Check to see air goes in and out of the tank through the open valve. With old tanks you always have to be careful they are indeed empty. It could be the valve is bad and you think the tank is empty when it is really not. You can turn the valve open with the knob and it feels like it’s open but it’s not. So before you try to put an 8 foot breaker bar on it.. just do a quick check…

Good luck my friend

Definitely good advice, but I always remove the burst disk (slowly) before removing the valve. Loosening the burst disk a couple of threads is the easiest way I have found to insure the tanks are empty if the valve handle is inoperable.