It finally happened - my CCR tried to kill me

Please register or login

Welcome to ScubaBoard, the world's largest scuba diving community. Registration is not required to read the forums, but we encourage you to join. Joining has its benefits and enables you to participate in the discussions.

Benefits of registering include

  • Ability to post and comment on topics and discussions.
  • A Free photo gallery to share your dive photos with the world.
  • You can make this box go away

Joining is quick and easy. Log in or Register now!

Dusty123

Contributor
Messages
178
Reaction score
139
Location
North Dakota
"Some people put another "moisture absorbing cloth" into the exhale lung, but Revo don’t recommend this."

Blasphemy! who does this? :wink:
 

stuartv

Seeking the Light
ScubaBoard Supporter
Scuba instructor
Messages
10,163
Reaction score
6,029
Location
Lexington, SC
# of dives
500 - 999
If you dive flat, any water in the exhale lung runs back down into the exhale loop up to the exhale mushroom. Eventually this bubbles back into the mouthpiece and gives you a 'wet' breathe.

You can do a shakedown manoeuvre to tip liquid back into the exhale lung. Don’t dive flat subsequently or it’ll tip back down.

Some people put another "moisture absorbing cloth" into the exhale lung, but Revo don’t recommend this.

Allegedly the BOV facilitates liquid clearing, but BOVs bring other challenges.

I have had a fair bit of water in the exhale side before, where it was gurgling a LOT on every exhale. But, I have never had a wet breath.

I do have the rEvo BOV, but I have no idea how it would help eliminate water from the loop.
 

Wibble

Contributor
Messages
1,999
Reaction score
1,566
Location
UK
# of dives
500 - 999
I have had a fair bit of water in the exhale side before, where it was gurgling a LOT on every exhale. But, I have never had a wet breath.

I do have the rEvo BOV, but I have no idea how it would help eliminate water from the loop.
I’ve found the DSV leaks water back through the exhale mushroom valve into the mouthpiece as water bubbles around the valve when exhaling. Maybe the BOV is different.

Someone told me once that the BOV (might?) allow water in the mouthpiece to be exhaled if the lever is half way. Never used one so can’t verify that.

"Some people put another "moisture absorbing cloth" into the exhale lung, but Revo don’t recommend this."

Blasphemy! who does this? :wink:

I guess the issue could be that the cloth moves and interferes with the ADV?

Does seem that a cloth could be very useful in preventing small amounts of water running back into the loop from the exhale lung when flat or head down.

Both times water ingress into the loop caused problems for me it was user error on my part: not properly tightening the DSV jubilee clips when replacing a mushroom valve; not squeezing out water from the breathing hose after cleaning.
 

Dusty123

Contributor
Messages
178
Reaction score
139
Location
North Dakota
Some what I don’t do is take the standard size sham-wow cut in half and use half in the inhale lung. Then cut the remaining piece in half again, roll, and place in the o2 side corner of the exhale lung bent into a 90 with half horizontal and half vertical. Supposedly if you put it in the other side it effects wob?
 

Dusty123

Contributor
Messages
178
Reaction score
139
Location
North Dakota
I thought the water at first was a loose lips issue, but it was never salty. Then I noticed if I was scootering everything was always dry. So it seems I just produce a bunch of water when Im swimming alot making co2.
 

Wibble

Contributor
Messages
1,999
Reaction score
1,566
Location
UK
# of dives
500 - 999
On the inhale lung there's the cable wrap anti collapse tube which stops the cloth from moving around. The inhale lung's much larger than the exhale lung -- I guess it is smaller to help 'push' the exhaled gas through the scrubbers. When you're below minimum loop, an inhale will suck the exhale lung closed against the ADV. Wonder if this may dislodge a cloth that's rolled and placed below the scrubber.

Does anyone "know" anyone who regularly puts a cloth in the exhale lung? If so has that cloth ever moved?

Following on from the last time I had a problem with a bit of water in the loop, I may well try that again.


Hmm, thought... if 'sucking' the ADV, I wonder if that might squeeze the liquid out of the cloth as it's shrinkwrapped.
 

Dusty123

Contributor
Messages
178
Reaction score
139
Location
North Dakota
Seems too me they could weld in a water trap into the bottom of the lung but would be difficult to clean without tools.
 

stuartv

Seeking the Light
ScubaBoard Supporter
Scuba instructor
Messages
10,163
Reaction score
6,029
Location
Lexington, SC
# of dives
500 - 999
I dived my first rEvo for a while using half a shamwow in the top and a half in the bottom. That was how I was taught by the instructor that did my original classroom training.

I never had any issues with that. It was never out of position after a dive. I never had any issues with interference with the ADV.

That was on a rEvo Mini.

Then I learned that the latest directions from HQ are to use a whole shamwow in the bottom and none in the top. I was told not to use one in the top in addition because it reduces CL volume. I have two thoughts about that:

1) I think that is based on the idea of using 2 whole shamwows, one top and one bottom. If you use 1 shamwow and put half in the top and half in the bottom, I don't see how that would reduce CL volume.

2) The Mini has much larger CL volume than a Micro. I had CL volume to spare in the Mini. I think I could have put 2 whole shamwows in and still had more useable CL volume than I get with 1 shamwow in a Micro.

Now I'm diving a Micro. The CL volume in that is just *barely* bigger than my normal tidal volume. I would be reluctant to put 2 whole shamwows in my Micro, because of the loss of CL volume. For ME, I think it might reduce useable volume too much.

Regarding putting one half in the top and one half in the bottom, my thought is that water in the exhale lung is annoying. Water in the inhale lung could result in death - via creation of caustic that runs down the breathing loop hose, starting a cascade of problems.

I think I'll stick with keeping the maximum amount of absorption capacity in the inhale lung and just deal with some annoying gurgling when it happens.
 

stuartv

Seeking the Light
ScubaBoard Supporter
Scuba instructor
Messages
10,163
Reaction score
6,029
Location
Lexington, SC
# of dives
500 - 999
Hmm, thought... if 'sucking' the ADV, I wonder if that might squeeze the liquid out of the cloth as it's shrinkwrapped.

I doubt it. But, you could test it. Wet a shamwow and put it in a Ziploc bag. Close it up except for a little bit and then suck on the opening to see if you can squeeze liquid out of the cloth. I doubt you can - but if you could, would it be with less pressure than what will crack the ADV?
 
https://www.shearwater.com/products/swift/

Top Bottom