Flooded 1st Stage

[Seaduced]

While in Bonaire a few weeks ago, on about dive 30, I noticed a change in my regulator sound. I have a Sherwood Oasis which continuously vents a very small amount of gas during normal operation. I could no longer hear this stream of bubbles, so I rolled on my back to do a bubble check and sure enough, no bubbles. Unsure about the severity of this situation, I signaled my wife something was "odd" with my 1st stage reg. I decided to continue the dive but stay closer to my buddy than normal.

After a few more minutes my primary started breathing a little harder and more wet than usual. I signaled my wife to hold up and deployed my octo. I took a few more breaths from the primary, then switched to the octo. It was breathing good. I purged the primary and tried it again, still harder to breath, so we aborted the dive and swam back to entry point underwater without incident.

I borrowed a friend's spare reg set for the rest of that day's dives. That afternoon when I described what happened to Bruce at Carib Inn, he said, water probably entered the 1st stage when it stopped venting. Sure enough when he opened it, there was water.

It was an easy dive, with a great buddy. To be honest (may get heat for this), if I had not noticed the lack venting of the 1st stage, I may have continued the dive on the octo. I would have chalked it up to a secondary problem. But with the 1st stage already questionable and now the primary 2nd having issues, I figured I was a few breaths away from a total failure.

It pays to be familiar with your equipment and aware of the subtle nuisances of it's operation. Now that I know what the venting means to the operation of the reg, any venting issue becomes an immediate abort.

To head off the inevitable question, the reg service was current.

 

[NAM001]

I am confused. flooded 1st stage or flooded primary second stage. Should not a flooded first stage effect both second stages/ lp outputs? Not to mention how do you flood a 1st stage. Must be a sherwood thing.

 

[Fishpie]

Good to hear you picked up on the lack of bubbles from your 1st stage......many don't and continue to dive their reg without noticing anything amiss until it comes time to service and the tech picks up on the blocked bubbler (mini sintered filter).
I wouldn't call it being a "few breaths away from total failure".
The worst case would be the ambient balancing process might have been compromised and the reg would have become progressively harder to breath from with increasing depth.

 

[Peter_C]

I have a Sherwood Oasis which continuously vents a very small amount of gas during normal operation.

That is not a "normal" operation of a reg. It gave you a warning that something was wrong and you didn't heed it, or you would have never gotten into the water with it. Now that you know what a normal regulator functions like, next time something like a regulator malfunctions abort the dive immediately, of which it sounds like is your future plans.

 

[NAM001]

peter i thought that bubbleing was normal for some sherwoods

 

[raftingtigger]

That is not a "normal" operation of a reg. It gave you a warning that something was wrong and you didn't heed it, or you would have never gotten into the water with it. Now that you know what a normal regulator functions like, next time something like a regulator malfunctions abort the dive immediately, of which it sounds like is your future plans.

There are regulators (and I'm assuming this is one of them) that are designed to vent a small amount of air to keep the ambient chamber free of water. The OP was being very astute and observant when his regulator stopped it's designed venting. It is a quirkly little design feature that most buddies will take for a malfunctioning regulator.

 

[herman]

That is not a "normal" operation of a reg. It gave you a warning that something was wrong and you didn't heed it, or you would have never gotten into the water with it. Now that you know what a normal regulator functions like, next time something like a regulator malfunctions abort the dive immediately, of which it sounds like is your future plans.

On Sherwoods it IS normal for them to vent a continous stream of bubbles. It is how they enviromentally seal the first stage. The stream of bubbles drive non Sherwood divers crazy but it's the best sealing method for piston regs available. It's simple but very effective, beats the dickens out of filling the spring chamber with goop like SP and Atomic do.

 

[WB2GLP]

Sherwood's let out a small stream that's equal to about 25ml per minute. Some variation in volume between models I believe.

I don't see how a 1st stage with 3000 psi on the HP side and 140ish on the LP side and a functioning octo is going to allow water to enter the system and deliver it to the low side and only route it to the primary.

Punctured diaphragm or mouthpiece i would believe. Knowing the Sherwoods, i would also suspect a loose purge cover that somehow unscrewed. When you get a chance, check and see if you have a new mouthpiece and/or a new zip tie on your reg.

 

[KeithG]

I agree with wb2glp that the OP should check elsewhere for the breathing issue. Your reg can stop bubbling and not have any immediate noticeable effect (at least I never noticed anything amiss). The only thing I noticed was my reg did not bubble and my buddies reg still did.

So I did some research and found the Sherwood patent.

this patented feature caused me to switch dive shops. When I took it in for service, it still did not bubble afterwards. When I asked the tech about it, they claimed bubbles would be a symptom of a leak and first stages should not have leaks. When I told them that the feature was to keep the first stage innards dry they laughed at me. Told me I was not a Sherwood certified service tech. Told me my reg worked just fine.

So I took my reg to another shop and got it serviced properly. Bought a lot of gear from the second shop since then...

 

[chrpai]

I did my OW and AOW at an AI resort in Jamaica using fleet regulators. Was used to the bubbling from day 1. Simple and solid they are. Just don't put one on a pony.