Bubble Check Problem

[ChrisEdwards]

The O ring is sealed between the male and female portions of metal threads. It serves as a seal because the threads cannot be machined to be totally self sealing or you would never be able to screw the male into the female.

If you have a compression fit, like water or natural gas hoses, used in building construction, the ends of these soft metal flanges deform as the are tightened, but are only expected to be tightened once and be left alone for 20+ years.

For your scuba gear, the O ring performs this seal, without deformation of the hose to component. Without the O ring, you would have to replace the hose and the component everythime you needed to repair/service and item that required disassembly.

The O ring is held is such a tight place that catastophic failure is just not going to happen, theres's no where for the (failed) rubber O ring to go.

If you are still not convinced, unscrew you spg from its hose, remove the O ring, screw the hose back in snug and connect it to a full tank. My guess is, without the O ring, the connection will leak, but it will take about a day and a half to leak 3000psi.

Oh, by the way, do this test on dry land.

 

[fldiver1]

I just don't take chances like this at all. I dive with several friends, a few of which are newly certified, and most of us have Jr OW kids. I carry a small tool kit EVERY TIME we go out. It's basically a plastic tray from a tackle box with every wrench, allen wrench, screwdriver, pliers I could need. In this kit I have extra o-rings for every hose/fitting or tank. Someone in our group always has a spare reg set, usually several of us. If we find bubbles, we fix it. Immediately! It doesn't take that long. If it's a tank o-ring it takes about 15 seconds. If it's a reg set, we switch sets. We will not dive with bubble streams. Not only does it waste your air(maybe not much of it but some) it could be a sign of a more serious problem. We also DO NOT WANT OUR KIDS seeing us use leaky equipment. That just isnt the way to teach them. Carry extra o-rings with you guys. They don't cost much. Even if you paid .25 each at a dive shop isn't it worth it not to have to abort a dive over a quarter?

 

[LittleBug]

I think I'd rather be safe than sorry. I am relying on this mechanism to give me air, and I'd rather not mess with that. If that makes me paranoid than I am happy with being paranoid.

I take the same approach when I am sailing. When ever we leave our bay, there is a navigation marker on the mouth of our bay. Going on the correct side of it takes longer than it would if I'd cut it. I know there's enough water for my 6' draft if I were to cut it. But I really don't want to get myself into the habit of cutting navigational aids that are there for a reason.

 

[BigTuna]

The O ring is sealed between the male and female portions of metal threads. It serves as a seal because the threads cannot be machined to be totally self sealing or you would never be able to screw the male into the female.

If you have a compression fit, like water or natural gas hoses, used in building construction, the ends of these soft metal flanges deform as the are tightened, but are only expected to be tightened once and be left alone for 20+ years.

For your scuba gear, the O ring performs this seal, without deformation of the hose to component. Without the O ring, you would have to replace the hose and the component everythime you needed to repair/service and item that required disassembly.

The O ring is held is such a tight place that catastophic failure is just not going to happen, theres's no where for the (failed) rubber O ring to go.

If you are still not convinced, unscrew you spg from its hose, remove the O ring, screw the hose back in snug and connect it to a full tank. My guess is, without the O ring, the connection will leak, but it will take about a day and a half to leak 3000psi.

Oh, by the way, do this test on dry land.

I don't know....

Suppose you have a steel tank and the leak is actually from the tank valve O-ring (but your buddy isn't sure). We have incidents reported on the board of the tank O-ring abruptly extruding itself out of its seat, resulting in a blasting freeflow.

Do you agree this scenario is possible? If you do and your buddy isn't sure what the leak's source is, now what would you do?

 

[SparticleBrane]

It's certainly possibly, and it's happened many times.
The simple answer to leaks: Find them before you get in the water with a spray bottle of soapy bubble solution. If there's leaks, fix them before you get in. A leak indicates that something isn't 100% seated properly, and there will be a failure in the future.
It might not be on that dive, or the next, or perhaps not even the next after that. But it's playing with fire...why risk it?

 

[in_cavediver]

I noticed everyone assumes the leak is from an o-ring, perhaps the yoke or din o-rings. I have personally seen a blown/leaking burst disc, and a blown diaghpram/hp seat. Both seem to me to be more important that '3 seconds and get on with it'.

Only a true fool would continue the dive without identifing the cause of leak.

 

[rjack321]

I'm with in_cavediver. If you know exactly what is leaking you can make a judgement about it. If you're clueless about gear, what might be causing the leak, or its potential to get worse - thumb the dive.

E.g.
The tiniest little leak from a burst disk unit and I'm bailing.
A tiny little leak from the vent hole on a DIN reg due to an old squashed O-ring, dive on.

 

[Diver0001]

You and your buddy have finished a bubble check at the surface. Your buddy tells you that you have a stream of small, discrete bubbles coming out from somewere in the neighborhood of your first stage regulator.

What do you do?

My first impulse would be to shut it down, tighten & try again.

If that doesn't work i'd closely inspect it to see where the source of the leak is.... I never used to do that but I had an experience a year or two ago where my buddy noticed a small leak like you describe on his deco stage and just tightened it up thought the problem was solved. We (obviously) didn't see it leaking during the dive but when he turned it on for the deco stops the 1st stage literally came apart at the DIN coupling and did the jacuzzi thing....

We were ok because ... well.... you train for these things and we had contingency plans. He also managed to feather it for the deco stops but the whole situation was an unnecessary complication.

Lesson learned: If you automatically assume it's just a worn O-ring (as we did).... think twice.

R..

 

[ChrisEdwards]

I don't know....

Suppose you have a steel tank and the leak is actually from the tank valve O-ring (but your buddy isn't sure). We have incidents reported on the board of the tank O-ring abruptly extruding itself out of its seat, resulting in a blasting freeflow.

Do you agree this scenario is possible? If you do and your buddy isn't sure what the leak's source is, now what would you do?

I'm not going to say it's impossible as I haven't seen it. In that situation I would expect that the valve stem was not installed/screwed into the tank properly so the O ring was not held in place. Secondly, for the O ring to come apart is would have to be seriously rotted out and thirdly, none of the rubber from the O ring would make it past the threaded potion between the tank valve and the tank, if the valve was seated properly. Without being held in place properly, no tiny diameter O ring is going to stand up to 3000psi.

I'm not suggesting anyone dive with a known leak or continue to dive with a new leak that starts, I'm just trying to say, most leaks, where a small bubble stream starts to appear, will not cause a massive loss of air.

 

[Crazy Fingers]

If we find bubbles, we fix it. Immediately! It doesn't take that long. If it's a tank o-ring it takes about 15 seconds.

It does not take 15 seconds. It might take 15 seconds to actually replace the O-ring itself, but you waste tons of time going into the water, determining there's a leak, then deciding to get out of the water, walk all the way back to your gear (which might be far away -- think Troy Spring), take the gear off, replace O-ring, put gear back on, walk all the way back to the water, and do the dive. God forbid the new O-ring leak a little too.

And let me ask you this... what do you do if you're on a charter boat and you get into the water and notice a yoke O-ring is leaking a little? Do you REALLY signal an problem and force that boat to come back and pick you up so you can replace it? Surely to God you don't really do that. If you do, then you are probably the most obnoxious person to be on a boat with... I'm sure the other passengers hate you and so does the crew.

Even if you paid .25 each at a dive shop isn't it worth it not to have to abort a dive over a quarter?

It's not about paying 25 cents. It's about not having to abort the dive over it at all. MILLIONS of dives have been done with leaky O-rings over the years. Grab any dive magazine and look at how 2/3rds of all pictures show divers with leaky yoke O-rings. If it bothers you, change it that night.

This board is known for its paranoia and ridiculous "safety" rules, but I think we have hit a new low.