OMS Performance Wing - Force required to use the Pull Dump

[Roy_W]

Hi All,

My wife has an OMS Performance Wing Mono and we have noticed that the pull dump requires such an effort to open the valve that she will not, or moreover , cannot use it during a dive...

It's difficult to put exact figures bit if I were to compare it to my Apex Black Ice, I would say that my stab requires around 1/2 Kg of force to open, whereas in comparison her OMS would require around 3Kg.

I tried a couple of stabs at the club the other day and most of them were around the same as my Black-Ice.

Does anyone have a performance wing and can they confirm if it is normal that it requires to much effort to operate..
her wing does indeed operate but the system they use requires the steel cable to pull on a small pivoting lever which in turn operates the valve. It's not a straight through pull like on many other system. I feel like the spring that keeps the valve normally closed is too strong for the lever system.. Obviously I will not cut the spring in order to reduce the strength as they would alter the present values of the over pressure setup..
I have just done a test and have noticed that the only over pressure valves that open when over-inflating is the lower valve , the top shoulder valve never opens automatically. ( it does if I pull the inflator hose, so it's not jammed).

In the following image we can see how that the steel wire has to use a little right angle pivoting lever inside in order to transform the direction of the pull.. The lever pushed up and against the spring that we can see..

Cheers for any feedback


.

 

[rongoodman]

Just replace it with a standard inflator. Problem solved.

 

[AustinV]

I have an OMS mono wing. The inflator pull dump does require a lot of force to open, so much so that I had the wing for over a year and never even knew that was a function until I noticed the lack of elbow (the valve was kind of tucked in that nylon loop and hidden, not sure if yours has same thing). I tried it in water once, didnt like the effort it took and found it much easier to just use the inflator itself to dump versus pulling if I wasnt able to use rear dump valve.

I eventually switched it out to a standard elbow from OMS, I likely still have the original and would gladly send it to you for free so you could compare but being in France/Switzerland shipping would probably be cost prohibitive.

 

[Roy_W]

Hi

I have an OMS mono wing. The inflator pull dump does require a lot of force to open, so much so that I had the wing for over a year and never even knew that was a function until I noticed the lack of elbow (the valve was kind of tucked in that nylon loop and hidden, not sure if yours has same thing). I tried it in water once, didnt like the effort it took and found it much easier to just use the inflator itself to dump versus pulling if I wasnt able to use rear dump valve.

I eventually switched it out to a standard elbow from OMS, I likely still have the original and would gladly send it to you for free so you could compare but being in France/Switzerland shipping would probably be cost prohibitive.

Hi AustinV:
Thanks for your offer, I wish I had read your post it a little earlier "before" I ordered a new dump valve assembly.. But you are right the delivery costs would probably outweigh the advantage of buying localy.

Anyway I am glad to now know that this is not a unique problem.. When I get the new assembly I might try working with the spring a little, since it does not open when the wing is overinflated I am sure that reducing a little of it's strength will not be a major problem... just cutting little increment of 1 cm, ( 3/8 inch ) or so at a time.. As long as the lower overpressure valves continues to operate first I know that I will still be in the safe realm...

Why do my wife and I want a dump valve, it's very simple we are preparing for our CMAS 3 Star level ( it's somewhere between a Padi Rescue + Padi Divemaster level) and it involves a lot of exercises bringing another diver up from 40m ( 120 feet).. This exercise requires regularly emptying the air from the other divers Stab and also your own whilst ascending at a controlled rate. The Pull Dump valve on your own stab makes this exercise much easier as we are diving in cold, dark water, in the Lake Leman ( Lake Geneva) and we have think gloves on ..

 

[AustinV]

Hi

Hi AustinV:
Thanks for your offer, I wish I had read your post it a little earlier "before" I ordered a new dump valve assembly.. But you are right the delivery costs would probably outweigh the advantage of buying localy.

Anyway I am glad to now know that this is not a unique problem.. When I get the new assembly I might try working with the spring a little, since it does not open when the wing is overinflated I am sure that reducing a little of it's strength will not be a major problem... just cutting little increment of 1 cm, ( 3/8 inch ) or so at a time.. As long as the lower overpressure valves continues to operate first I know that I will still be in the safe realm...

Why do my wife and I want a dump valve, it's very simple we are preparing for our CMAS 3 Star level ( it's somewhere between a Padi Rescue + Padi Divemaster level) and it involves a lot of exercises bringing another diver up from 40m ( 120 feet).. This exercise requires regularly emptying the air from the other divers Stab and also your own whilst ascending at a controlled rate. The Pull Dump valve on your own stab makes this exercise much easier as we are diving in cold, dark water, in the Lake Leman ( Lake Geneva) and we have think gloves on ..

Sounds good - best of luck on your certification. Set up your equipment as you see fit best, there is nothing functionally wrong with having a pull dump there, I just swapped for a rigid elbow so I would have one less valve to worry about cleaning/maintaining, especially as I wasn't using it.

 

[fast_mag]

The thread is a bit old, but I thought I should share my experience with this apparently general problem.

I had the same problem with the OMS dump valve being more than very stiff. After some fiddling I realized that:
1) There is no problem with the dump valve itself.
2) The rubber hose is too short, thus there is slack in the internal line. As a consequence, to open the dump valve the rubber hose has to extend a lot.
3) The rubber hose is VERY stiff.

Three possible solutions: Shorten the internal line, replace the rubber hose with a longer one, or replace the rubber hose with a more flexible one.

I went for a longer more flexible rubber hose and problem solved.

 

[happy-diver]

Nice job chief!

If you move to a country closer to the Equator you may find yourself swapping back

 

[rongoodman]

Three possible solutions: Shorten the internal line, replace the rubber hose with a longer one, or replace the rubber hose with a more flexible one.

Or throw away the pull dump and replace it with a standard inflator hose.

 

[fast_mag]

Or throw away the pull dump and replace it with a standard inflator hose.

Well, the 32lb oms perf wing has only two ports. If you want a high and a low dump valve you need to keep this one.

 

[fast_mag]

Nice job chief!

If you move to a country closer to the Equator you may find yourself swapping back

I don't actually use this one in cold water. Why would I like to change closer to the equator?