Regs do not always free flow when they fail

[tbone1004]

not the pnuematic spring, the physical spring. If it had salt buildup and wasn't able to slide inside of the barrel it could get physically stuck or have enough resistance to add to the normal spring resistance which wouldn't allow the IP plus the inhalation pressure to overcome the spring pressure.

If you look at the orifice on the barrel the spring on the shuttle valve, if there's salt deposits in there causing the spring to catch, it could catch open in the case of the first second stage failing, or at depth, the ambient pressure is enough to keep the balance mechanism from working properly and the added resistance from the salt building could cause the shuttle to stay put.

 

[redacted]

not the pnuematic spring, the physical spring. If it had salt buildup and wasn't able to slide inside of the barrel it could get physically stuck or have enough resistance to add to the normal spring resistance which wouldn't allow the IP plus the inhalation pressure to overcome the spring pressure.

I agree but don't see how that would be depth dependent. And I can't imagine how so much salt could build up on that spring. Perhaps some other contaminants. Maybe we will learn more.

 

[Steve_C]

OK, I was able to check with one of the diver's (who is also an equipment guru).
xxxx is an equipment guy who was not on the boat.

"xxxxx said the lever was broken, but he hasn't pulled it apart yet.
When I took the cover off yyyyy's primary, the one that failed closed, the level
was down. It should be in the up position. I played with it a little. It seemed
that it wasn't seated in the barrel properly, like it had been hit on something.
After I got it positioned correctly, it was working correctly. I still wouldn't have
gone diving with it until is was completely serviced."

So the problem seems to be possibly the result of physical abuse/trauma resulting in a defective arm.

---------- Post added October 27th, 2014 at 01:04 PM ----------

Got some more information:

"xxxxx took yyyy's regs apart. The poppet seat assemblies were inserted incorrectly into the barrel.
One was sideways (octo) and the primary's was upside down. Good reason not to service your own gear."

yyyyy was a very experienced diver but had not been actually trained in service. Just did it figuring it looked simple.

 

[undrwater]

Human error. Not regulator malfunction.

 

[Steve_C]

Human error. Not regulator malfunction.

Yep. And reassuring in some ways.

 

[LeadTurn_SD]

OK, I was able to check with one of the diver's (who is also an equipment guru).
xxxx is an equipment guy who was not on the boat.

"xxxxx said the lever was broken, but he hasn't pulled it apart yet.
When I took the cover off yyyyy's primary, the one that failed closed, the level
was down. It should be in the up position. I played with it a little. It seemed
that it wasn't seated in the barrel properly, like it had been hit on something.
After I got it positioned correctly, it was working correctly. I still wouldn't have
gone diving with it until is was completely serviced."

So the problem seems to be possibly the result of physical abuse/trauma resulting in a defective arm.

---------- Post added October 27th, 2014 at 01:04 PM ----------

Got some more information:

"xxxxx took yyyy's regs apart. The poppet seat assemblies were inserted incorrectly into the barrel.
One was sideways (octo) and the primary's was upside down. Good reason [-]not to[/-] to have half a clue if you plan to service your own gear."

yyyyy was a very experienced diver but had not been actually trained in service. Just did it figuring it looked simple.

Fixed that for you.

Those type of assembly errors are mind-boggling.

Nothing wrong with servicing your own gear, but you do need to understand how, and pay attention to detail... you know, like paying attention to the correct orientation of those pesky bits and pieces... little stuff like that :shocked2:

Once again, the most common cause of actual catastrophic regulator failure (defined as a regulator that suddenly will not deliver air) is almost always human error at the time of servicing, not the regulator's design or inherent reliability. Over and over again, it is sloppy servicing that creates the drama.

Best wishes.

 

[industrious95]

Second DM dove with the REG but carrying back up air. The reg again stopped completely at 60 ft on a full tank of air but it did not matter since he had plenty of redundant air with him.

.

Isn't that an unusual way to test a malfunctioning regulator? Wouldn't a test bench be a little safer?

 

[Steve_C]

He was not testing the regulator. There was only one set of gear for the DM setting the hook that was not on a customers back. That was why he took the pony. It had sufficient gas to set the hook. Then while the customers enjoyed the dive they set up another set of equipment. Probably from a rental unit since several divers were done well before hook pulling time, I am not sure.

 

[tbone1004]

that was tongue in cheek doc.... Thanks for posting though, always a good laugh when professionals don't take care of their gear.

 

[Bob DBF]

Isn't that an unusual way to test a malfunctioning regulator? Wouldn't a test bench be a little safer?

It would depend upon the ability to test those conditions at the particular bench. My bench does not have that ability, so I would be inclined to do a test dive. Safe is as safe does, to paraphrase a movie character, having redundant gear available while testing a known POS sounds safe enough to me.



Bob
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I think that advocating unsafe and dangerous practices is both stupid and foolish. That is why I don't tell people to do what I do. Dsix36