A problems of Oxycheq OPV leaking.

[Jan Chan]

Hi, I have a new Oxycheq 30# mach V chroma series wing, it have a problems of OPV leaking.
The new bcd after fully inflated will leak by 50% over the span of 12 hours. After testing, the bcd a leaking right at the OPV valve.

I email this problem to oxycheq, they reply as follows:

'When we test the wings in shop, we fill them up until the dump releases ... at 5psi internal pressure.
When there is no external pressure (like in the water), the dump will not seal and a very slow leak will result.
After filling your wing, pull on the dump to release the pressure and seat the seal. One quick pull is all that is needed. '

This mean normal of the wing leak?

This is my test video

https://youtu.be/HNH2w6n8LGw

[jb2cool]

If you unscrew the valve and look inside it is it clean? Something like that could easily be caused by a bit of trapped grit or something

[Jan Chan]

I sure that the OPV is clean, and more than one has same porblem. So I difine that is a design bug.

[turnerjd]

Many aqualung and mares BCDs do that too, or at least the ones I have used do so. Scubapro and Buddy strangely don't. I know to watch out for students overfilling prior to doing surface skills. Mind you, most of the time you can hear the air as it continues to escape.

It's a bug with the type of cheap, simple overpressure valve.

(Yeah, I know BCDs aren't wings, but the valves are the same)

[N Bailey]

IS it a CE marked item?

[Ian_6301]

Sometimes the OPV just fails to seat nicely?

Design fault for sure, but you might be able to live with it.

OPVs are a fairly standard part though, so you might be able to just replace it with a good one from somewhere else?

I think OMS and Custom Divers sell OPVs as a separate spare part, plus AP Valves might too... try this: http://www.apdiving.com/shop/spares/...yant-knob.html but check the diameter of the hole.

[Jan Chan]

Maybe I will replace other brand OPV valve, but I lose confidence for oxycheq

[bubbleless]

Does it seal if you give it one quick pull on the dump as suggested??

[Jan Chan]

Does it seal if you give it one quick pull on the dump as suggested??

No improve after test

[bubbleless]

If it is new then get back to oxycheq and ask them, if the test they use does not seal the vent then there is a fault somewhere , a simple clean may work, but the opv is a simple device , a spring and a piece of rubber, and a plastic housing, you may find the part on the bladder is bonded to the valve.

Have you disassembled it and cleaned it, check the rubber seal etc and the plastic that is seals on.

[Jan Chan]

If it is new then get back to oxycheq and ask them, if the test they use does not seal the vent then there is a fault somewhere , a simple clean may work, but the opv is a simple device , a spring and a piece of rubber, and a plastic housing, you may find the part on the bladder is bonded to the valve.

Have you disassembled it and cleaned it, check the rubber seal etc and the plastic that is seals on.

I cleaned the rubber seal last night, testing now.
Oxycheq told me that the slow leak is normal, but I don't thing so. However, I used a larger rubber gasket, the leak has improve. But the larger rubber gasket only for test, not for dive.
I want to changing the spring to a tighter ones, but need to time for purchase

[Energy58]

If a BCD/wing retains 50% of its gas after 12 hours then I wouldn't get excited about it - its not a life jacket after all. If you put a stronger spring in you defeat the purpose of the OPV which is to protect the jacket from pressures in excess of those it is designed to deal with by providing a controlled safe way of dumping the excess gas. Put a strong enough spring in and you will stop the "leak" but risk the jacket failing catastrophically somewhere else when (over)pressurised on the surface which is a BAD THING (trust me I know it happened to me when the elbow connecting the LPI corrugated hose to the body of the jacket broke in two - in the dark, 500m offshore)

[turnerjd]

You know what, I think that this is a non problem. Energy58 is right about changing the spring, but I think that there is something more important here.

The best solution is just to learn to inflate the wing the right amount and not over-inflate it. Most of the time, if you don't over-inflate it, the OPV doesn't open, and you get much less gas lost from an OPV that leaks immediately after opening.

If I was testing a BCD/wing I would want it to stay nicely inflated for an hour or so, and I wouldn't be concerned about longer time periods.

[Jan Chan]

I solved the leak problem. One day, I discuss this problem with other dive shop, he said that he had same problem in 2 years ago.

The bugs has been found at the plastic ring wrapped around the bottom of the OPV which causing such a leaking, rather than the slingshot and rubber gasket. Such a bug is caused by crackles on the uneven surface of the plastic ring and is fixed after the plastic ring is polished and smoothen.

This is a matter of the production quality rather than a design bug.