My BCD keeps pushing me down to the right (Tusa Selene Wing)

[jamjam]

Hi all,

I have a Tusa Selene Wing back inflate bcd, which I've been using for a year now. I noticed this problem a few months back but it seems to be getting worse:

When I'm horizontal/flat during a dive, I keep 'falling' or listing down to my right so that I end up facing leftwards. I have to constantly fight this to just stay horizontal. Not sure if my left side is lighter or the right is heavier. I've tried adding extra weight to the opposite side but it over compensates and I end up listing that way.

I also noticed that I get a lot of water into my bcd and wondering if this has to do with it...

A friend who bought the same bcd with me is having the same exact issue.

Any help would be MUCH appreciated!

cheers!!

 

[SangP]

I'm not familiar with the bcd in question but many of the issues you mentioned could be due to these reasons.

1. A lot of water in wings could be due to excessive venting cus overweighted or due to bounce diving.
2. Adding extra weights to either the left or right only makes the problem worse.
3. Leaking bcd or valves which could be seen with some soapy water and inflated wing.
4. The bcd is not as secure as it can be on the body leading to twists etc.

Without more info I can only think of these reasons.

 

[jamjam]

Hey SangP! Thanks!

Just a question - wouldn't there be excessive venting if you're underweighted? Trying to purge as much as possible to go down?

Also, what do you mean when you say leaking bcd or valves can be seen with soapy water?

thank you!!

a

 

[Diver0001]

Also, what do you mean when you say leaking bcd or valves can be seen with soapy water?

Just fill it all the way up with air until the over-pressure valve opens and leave it for 10 minutes. If it loses any air in that time then you may have a leak in one of the valves. Also visually check everything to see if it looks right and indeed drain any water out of it that may have accumulated.

I doubt that a slow leak would cause your problem though.

Your problem is almost certainly one of two things:

1) the air inside the BCD is somehow accumulating on the left hand side more so than on the right hand side.
2) something you're carrying on the right hand side of your body is negatively buoyant.

If it's #1 then it could be caused by a restriction. I don't know that BCD very well but the only way for air to get from the left to the right is for it to migrate across via the top of the wing. Also, the inflator is on the left side, so when you add air it's going in the left. My *guess* having not seen you in the water, is that you dive very horizontally (or even a bit heads down) which causes more of the air you add to the BCD to accumulate on the left hand side.

A normal jacket doesn't have this problem. What you need to do if you're listing is to "force" air to migrate to the right. Do that by rolling to your left side (and maybe look up in the process to cause yourself to go slightly vertical) and count to 5, which will give the air in the BCD the opportunity to migrate from left to right and balance out.

If this is your problem then you'll probably notice that it's "worse" on deeper dives than on shallower dives and forcing the air to move to the right will probably fix your problem.

If it's #2, then your solution is really easy. Just move 1kg of weight to the other side of your body to compensate for anything you might be carrying on your right (like a canister light, for example) that could be negatively buoyant on that side.

good luck.

R..

 

[SangP]

Hey SangP! Thanks!

Just a question - wouldn't there be excessive venting if you're underweighted? Trying to purge as much as possible to go down?

Also, what do you mean when you say leaking bcd or valves can be seen with soapy water?

thank you!!

a

If you are underweight you won't be able to go under. If you are overweight, you'll need to inflate your bcd more underwater to compensate, the more air you have in your bcd the more adjustments you need as you go up or down as the air compresses or expands.

Imagine this, suppose a diver needs 1L of air in his bcd at 30m to have neutral buoyancy. However at 20m, the volume becomes 2L so he needs to vent 1L of air or thereabouts to get neutral.

Now an overweighted diver needs 2L of air in his bcd to be neutral at 30m, now at 20m he needs to vent 2L to stay neutral.

The more weight you have the more you have to vent.

To test for leaks you inflate the bcd to the max, then apply soapy water all over, where you see bubbles, there's the leak.

Air moves more freely in a wing then in a jacket type bcd so unless you have a lot of weight on the left or right I don't see how difficult it is to simply spread your legs apart like you are flying and then to shift your body to the left or right to transfer the air accordingly.

What I suspect is that you are over weighted from the start and cus you vent often resulting in water intrusion and air trapping.

What exposure suit are you currently using and what weights you are using?

 

[oly5050user]

you may be using too much weight..using too much lead causes you to add excessive air into bc to get neutral at depth..You now have a fairly large bubble of air moving around in the wing. Do a buoyancy check, only sink from surface with an empty bcd and during a FULL exhalation, use minimal lead and you will find that you will not need to add so much air to bcd thus eliminating a large bubble of air moving around in it..fact that you have water in it is a give away that you probably need to work on eliminating some lead weight..

 

[supergaijin]

When adding air through the direct system, it sounds like it is going only in to the left side chamber of the wing. Sounds kinda odd to me, but it could be happening. However by momentarily adopting an upright position in the water, the air should balance in each side of the wing.

If you return to a horizontal position, and still drop on one side, it sounds like you're finning technique is a little lopsided.

A great tool to see what you're doing is if you can get someone to take some video footage (many digital cameras have a video function).

Spreading your legs somewhat helps with balance. If your fins knock together while swimming, it may help to slightly widen your stance.

 

[Blackmore75]

My back inflate does the same thing occasionally, and I have to dip the other shoulder to balance it and get the air bubble to shift a little.

 

[jamjam]

Wow, thank you for all the advice, everyone. Super cool!

So I think I need to check two things on my next dive:

- my weights (and I agree, I think I've been overweighted lately)
- moving around to shift air in the wings

Can't wait to try this out - this listing to one side has been a real annoyance on my last few dives!

Thanks!

a

---------- Post Merged at 08:27 AM ---------- Previous Post was at 08:25 AM ----------

0.5mm so not very thick. I was using 8lbs and then got very very sick for a few months. When I got back to diving, I was a little nervous, so overweighted up to 12lbs. So I think you're on the money with that

---------- Post Merged at 08:29 AM ---------- Previous Post was at 08:25 AM ----------

Yes, very horizontal. I'm going to try the going vertical and rolling to my left maneuver. If it's air pockets, then that should help...

Thanks!

 

[TSandM]

One final idea -- if your shoulder straps aren't adjusted evenly, the tank may be sitting off-center, and that will definitely make you list.