First stage clicking?

[billindenver]

So we took our new oceanic GT-3/CDX5 regs in the water this weekend at Homestead crater. Warm water was a nice change. The first dive was Tonia's open water cert dive which I just swam around and watched. The second dive she and I went for a 55 min bouyancy practice and emergency procedures fun dive. One thing struck me as odd that I would like more experienced minds to work on.

When we first got in the water on the second dive, for about 5 minutes when I would inhale lightly or when the inhale first started my first stage would make a loud click click click noise during the inhale. If I inhaled deeply it stopped. After 5 minutes or so it stopped altogether. It was pretty loud, and really seemed to be coming from behind my head but you know how sound in water is. I guess it could have been something else, or even my second stage but was certainly breathing related and only when I inhaled softly.

Any thoughts from the more expert than I?

Also, we have new xs scuba inline airwave alternate air sources which neither of us find very easy breathing. Sure, they work and all..but has anyone else found them to be a bit rough on the air delivery?

 

[pescador775]

That regulator may have a check valve in the first stage inlet. I forget what it is called, like dry-hype or something. Don't worry about it.

 

[300bar]

Guess you mean the DVT,but it's very unlikely that the DVT will do this.
It's located on the outside of the 1st stage and under constant pressure from the tank.

 

[pescador775]

Guess you mean the DVT,but it's very unlikely that the DVT will do this.
It's located on the outside of the 1st stage and under constant pressure from the tank.

Think again.

 

[halocline]

It's possible that it has something to do with the DVT. Some of those set ups equalize in pressure between the tank valve and the HP chamber in the reg, so if the DVT ball is held shut with a spring, it only opens during inhalation. I don't know if this particular reg is like that, but I do know that some of the auto-close features do in fact open and close with each breath. So, maybe this one is one of those. Yet another reason to avoid regs with this useless "feature."

 

[Jimmer]

It's possible that it has something to do with the DVT. Some of those set ups equalize in pressure between the tank valve and the HP chamber in the reg, so if the DVT ball is held shut with a spring, it only opens during inhalation. I don't know if this particular reg is like that, but I do know that some of the auto-close features do in fact open and close with each breath. So, maybe this one is one of those. Yet another reason to avoid regs with this useless "feature."

This is one of those cases where it is held in place by a spring, so the fact that it only makes noise on inhalation makes sense. Nice reg, but get it swaped to a DIN fitting and then you dont need to hassle with the DVT.

 

[billindenver]

Ok, so the problem has been found. The first stages we have are not DVT (which was my intent when I bought them), but the pre-DVT's had a recall on some of them. Apparently one of ours was included in the recall. I took them both down to an authorized Oceanic dealer who hooked the noise making one up to their machine. It made a racket when the the primary reg was used so he took it apart. There is a valve seat (I think that's what he called it) in there that looked like it had 2000 dives on it according to the tech. Since it only had three, he deduced it must be one of the bad ones from several years back that had been sitting on a shelf at Divers Supply for a while. So, he swapped out both of ours just in case (the other looked fine) with the updated seat and.....voila, no more noise. He told me I was a bit lucky...when they fail, they typically really fail and the diver gets 3000psi at his mouth....not pleasant.

So, problem solved...but not real happy that there was a recall on a regulator that I bought new from Divers Supply and they sold it to me without the update. I'll get over it, but in a life safety piece of equipment...I would expect a bit more attention paid by the dealer. If we hadn't taken that trip to Utah just to test our new gear...I would have found this problem in Cozumel next month at 100fsw.....the more I think about that the less happy I am. If it had been my girl's regulator making that noise and then going back quiet she may have ignored it whereas it stayed in the back of my mind to have checked when we got home. This could have ended badly I'm thinking....

 

[halocline]

First stage HP seats are not closed when the reg is not pressurized, so having it sit on a shelf for years would not cause it to wear out like it "had 2000 dives" on it. If the seat was really worn out, not just a bad material or some other problem, the only reason would be it was used. You might want to clarify that with the tech, or call Oceanic.

I understand your concern about HP seat failure at depth. It really should not be life-threatening, though. That's why we have the buddy system, as well as immediate access to the surface in OW diving. Still, something doesn't have to be life threatening to be unpleasant and scary!

 

[tfsails]

I'm not defending anybody here; just want to clarify some things for the OP and others. I service regulators for a "living" (in addition to my gov't retirement checks...), so that should qualify me to make these clarifications.

Concerning the primary second stage: that "valve seat" would be properly called the "poppet seat" and it handles only about 140 psi, not 3000. The first stage of a two-stage regulator is the only one handling high pressure. On the vast majority of regulators, Oceanic included, the poppet seat is held closed against the orifice by spring pressure whenever the diver is not demanding it open by inhaling on the stage. The closing force is greater when the reg is unpressurized than when pressurized. All this adds up to the poppet seat's taking a set as it remains pressed against the sharp edge of the orifice over time. I'm not familiar with the Oceanic recall on this second stage (my shop is an Aeris dealer), but I'd suspect that the noise came from the seat's barely opening and the air taking a circuitous route around the gap.

The first stage of a DVT reg does make some funny sounds. I've attributed them to the fact that when the first stage "locks up" (air flow ceasies when IP is reached and the HP seat/poppet close up) air pressure immediately downstream from the DVT plug (and upstream from the HP seat/poppet) equalizes with tank pressure. This equalization will cause the DVT valve to close up as if the reg were unpressurized. As soon as you breathe on the reg, the IP drops, the HP poppet opens, and air flows from the tank into the first stage. But first the air has to overcome the spring pressure from the DVT plug and move the plug. This makes noise. I've only heard this on DVT first stages, but it's a normal sound. Aeris and Oceanic are essentially the same company and have a lot of commonality between their regulators. I've seen lots of Aeris and some Oceanic DVT first stages, and the vast majority of them make this noise.

A little anecdote: the first several times I dove my own regulator after the first time I rebuilt it I heard all kinds of funny noises and clicks and burps and wondered what kind of catastrophe awaited me when it finally blew up. Nothing ever happened. I've since rebuilt it again and don't even hear it any more. It still makes all those noises, but I've either gotten used to them or have subconsiously come to the conclusion that all regulators make some noise and that's normal.

 

[redacted]

Ok, so the problem has been found. The first stages we have are not DVT (which was my intent when I bought them), but the pre-DVT's had a recall on some of them. Apparently one of ours was included in the recall. I took them both down to an authorized Oceanic dealer who hooked the noise making one up to their machine. It made a racket when the the primary reg was used so he took it apart. There is a valve seat (I think that's what he called it) in there that looked like it had 2000 dives on it according to the tech. Since it only had three, he deduced it must be one of the bad ones from several years back that had been sitting on a shelf at Divers Supply for a while. So, he swapped out both of ours just in case (the other looked fine) with the updated seat and.....voila, no more noise. He told me I was a bit lucky...when they fail, they typically really fail and the diver gets 3000psi at his mouth....not pleasant.

So, problem solved...but not real happy that there was a recall on a regulator that I bought new from Divers Supply and they sold it to me without the update. I'll get over it, but in a life safety piece of equipment...I would expect a bit more attention paid by the dealer. If we hadn't taken that trip to Utah just to test our new gear...I would have found this problem in Cozumel next month at 100fsw.....the more I think about that the less happy I am. If it had been my girl's regulator making that noise and then going back quiet she may have ignored it whereas it stayed in the back of my mind to have checked when we got home. This could have ended badly I'm thinking....

Oceanic regulator recalls in the last 8 years were on 1st stages, not 2nd stages. Which stage was the tech commenting on when he said, "looked like it had 2000 dives on it". And which stage did the tech swap out parts on? The comment about getting 3000 psi at his mouth relates to the first stage recall failure mode. But the comment aboput the "valve seat" looking like it has 2000 dives sounds like it is a 2nd stage.