MonkSeal
Contributor
Probably they have in mind diving population that deserve to be charged for servicing. Divers that use solutions for non-existing problems are probably more easier to charge then people who understand thing or two.
Pull dump or non exhaust elbo
- Thread starter plclark196
- Start date
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
Reg Braithwaite
Contributor
My wing came with a pull dump, and in my n00b ignorance I didn't know it could be pulled until I was diving "The Kinghorn" at 90' and my wing would gradually lose buoyancy. A buddy warned me that the valve was leaking, and back on the boat we fixed it. While fixing it, I noticed the assembly and he explained what I was looking at.
Since then I was happy to use it when in a heads up position, but noticed that when "in trim" it was easier to hold the hose up rather than break trim, so I only used it when vertical for other reasons.
Then I started looking into DIR and was told to use the rear dump. Aha! I had been pulling on the string only when rinsing and dumping the bladder!!! Much better actually using it during the dive. And when I read that pull dumps were a source of failure, I immediately thought of that failure on a dive and another light went on.
I am now torn between replacing the entire pull assembly with a shorter hose and plain elbow or saving up and buying a better wing. But in the mean time, I do not pull on the hose and I inspect the valve before getting into the water. So it's one more d*mn thing to check with no benefit to me.
YMMV, but the DIR answer seems clear. There's one dump too many on my wing.
Since then I was happy to use it when in a heads up position, but noticed that when "in trim" it was easier to hold the hose up rather than break trim, so I only used it when vertical for other reasons.
Then I started looking into DIR and was told to use the rear dump. Aha! I had been pulling on the string only when rinsing and dumping the bladder!!! Much better actually using it during the dive. And when I read that pull dumps were a source of failure, I immediately thought of that failure on a dive and another light went on.
I am now torn between replacing the entire pull assembly with a shorter hose and plain elbow or saving up and buying a better wing. But in the mean time, I do not pull on the hose and I inspect the valve before getting into the water. So it's one more d*mn thing to check with no benefit to me.
YMMV, but the DIR answer seems clear. There's one dump too many on my wing.
The stress (or failure point) is not the bladder - it is the pull dump itself (that's why we ditch them or more correctly, don't bother buying a wing that has one).
String getting caught would be an entanglement issue, not a failure point. As long as the valve is there, it can still fail - (not that big a deal as it is located on the bottom side of the wing). One day on a dive with SparticleBrane, just for fun, he totally removed his rear dump leaving a gapping hole in his wing. He was able to do the entire dive with no buoyancy issues (and he could dump gas when needed hands free
).If your desires are to learn to dive DIR, ask all the question you want, but it is obvious that when you leave the pull dump on the power inflator and remove the rear one that you are just looking to start *****. Go find a dumpster to dive in.
cmburch
Contributor
I did not notice that I was in a DIR section. I will check out what DIR is.
Last edited:
Reg Braithwaite
Contributor
Never mind. The point was entirely too obvious,and therefore no comment of mine could add value to the thread.
SparticleBrane
Contributor
I have to say, that was the easiest ascent of my life.Jason B.:
rainman_02
Contributor
Welcome to the DIR forum, where answers to questions are supposed to be DIR (or debating it, not blatantly violating it).
As for the "primary" method of dumping...to say the butt dump is primary is BS. The two standard dumps (one on the inflator and the other on the butt of the wing) should BOTH be easily usable as you do not always have the option of using one or the other.
When inside a wreck and changing levels perhaps the inflator dump is better than the butt dump (depends on body position). When scootering, I find the butt dump is easiest due to normal body position. When ascending, I can dump from my wing and my suit with a simple wrist/shoulder motion by using the inflator dump as well as keep my teammates easily in sight...versus going slightly head-down to use the butt dump.
This is one of those silly forest-for-the-trees arguments that waste most our time on the internet. Know how and when to use both dumps (and do not have a pull dump on the inflator hose).
As to failure of the inflator hose assembly, I've been in two situations where new divers at my shop pulled too hard -- *snap* went the pull dump cord and off came the inflator hose. This is not a "I heard it on the internet or a friend's brother's monkey's uncle had it happen," this is a "I saw it happen myself...twice." I've also seen an experienced diver I respect pull his dump off...and after he did that he said, "maybe there is something to that non-pull elbow you have on there that I always made fun of..."
dumpsterDiver
Banned
- Messages
- 9,003
- Reaction score
- 4,657
- # of dives
- 2500 - 4999
??? You know that removal of the string doies not affect the OPV function of the device????
dumpsterDiver
Banned
- Messages
- 9,003
- Reaction score
- 4,657
- # of dives
- 2500 - 4999
The stress (or failure point) is not the bladder - it is the pull dump itself (that's why we ditch them or more correctly, don't bother buying a wing that has one).
String getting caught would be an entanglement issue, not a failure point. As long as the valve is there, it can still fail - (not that big a deal as it is located on the bottom side of the wing). One day on a dive with SparticleBrane, just for fun, he totally removed his rear dump leaving a gapping hole in his wing. He was able to do the entire dive with no buoyancy issues (and he could dump gas when needed hands free
If your desires are to learn to dive DIR, ask all the question you want, but it is obvious that when you leave the pull dump on the power inflator and remove the rear one that you are just looking to start *****. Go find a dumpster to dive in.
I was not trolling. It was a serious question about a pull dump pulling the bladder threough the shell and why a similar thing does not happen with a rear pull dump. I've never ripped out an inflator hose, but I have had the OPV at the top of the hose fail and render the BC useless (I never thought of trying to do an inverted ascent).
Last edited:
cool_hardware52
Contributor
Having designed and manufactured OPV's I do have a reasonable working knowledge of their construction and operation.
A "bare" pull cord, i.e. without any knob or "toggle" is very unlikely to get caught on anything.
All you have achieved is the elimination of a benefit, i.e. venting via the OPV with no attendant increase in reliability.
Tobin
Similar threads
