BCD Question

[Ronniemu]

I am a recently certified diver and I realized it's only the beginning of an education in diving. I have many questions. These questions are on the BCD which I was practicing in my pool.

1) I have a newly purchased BCD by Seaquest (it's the balance model). I always have trouble getting the air completly out when descending. I had tried the inflater/deflater valve and or the dumps. Regardless which method I use there is always some air left.

2) The BCD always gets some water in it when diving. Is this normal? I believe if your releasing air from it and no more air comes out that water must enter?


Thanks for all replies, Ronnie

 

[DiverEMT]

Getting water in your BC is normal. When you get home use your dump valve to get the water out.
As for the air in your BC I've never seemed to be able to get the air completely out when I decend. And even after my dive I have to lay on it to get the air and water all out. I'm guessing that is also normal.
Someone else can probably tell you more than I can about that.

 

[ScubaSixString]

I am a recently certified diver and I realized it's only the beginning of an education in diving. I have many questions. These questions are on the BCD which I was practicing in my pool.

1) I have a newly purchased BCD by Seaquest (it's the balance model). I always have trouble getting the air completly out when descending. I had tried the inflater/deflater valve and or the dumps. Regardless which method I use there is always some air left.

2) The BCD always gets some water in it when diving. Is this normal? I believe if your releasing air from it and no more air comes out that water must enter?


Thanks for all replies, Ronnie

Welcome to the world of diving

1>Its a trick. you'll have to experiment with body position versus the dumps. Remember air always rises in water so make sure the dump in question is at the highest point. BUT.... why would you ever want to get ALL the air out of your BC? (except maybe when your tank is near empty.) If you have to do that before then, add some more weight (IMHO)

2>perfectly normal. Its caused by raising your inflator valve and dumping air. When you get back to dry land put some air in your BC, turn it inflator side down, and depress the dump button. The water should drain out.

 

[MrConclusion]

EDIT - ScubaSixString posted a while I was writing, so I have become redundant! I'll leave what i wrote anyway.

Ronnie,

When you're venting the air from the BC, be awaren of the position of the dump valve in relationship to the rest of the BC's air bladder. You need to orient yourself so that the dump valve (whichever one you use) to be the absolute highest spot on the bladder, or else there will be some air left in the bladder above the dump valve - there's nothing to force it down-and-out, it needs to go up-and-out.

For instance, the rental BCs that my students use. They hold the inflator up and press the dump button... thinking that all the air will come out. But if you look at the BC, the shoulder attachment point for the inflate/deflate hose is somewhat below the highest point of the bladder. It kind of sits back on the shoulder blade, and there is air trapped above it whare the bladder crosses the back of the wearer's neck. SO, to fully dump, you need to bend forward and tilt a little bit to the right. This brings the dump valve to the high point, and more air comes out. When a student has problems descending, I take a few seconds to show them how to reposition themselves for a complete deflation, and then they usually "get it" forever.

You may want to reach back over your shoulders and feel where the dump valves are located when you're trying to dump. Some BCs will shift position depending on whether you're in the water or not - so looking while on land might not solve it.

 

[jamiep3]

Try this,

Assume an upright position in the water.
Raise your left shoulder slightly while holdiong your inflator up with left hand.
Press the release till no more air comes out.

This should get about 99% of the air out of your BC. You may have to repeat the process to get the last bit, because anywhere that a pocket can form, most particularly your other shoulder area will tend to trap air.

Good Luck.

 

[mossym]

Getting water in your BC is normal. When you get home use your dump valve to get the water out.

when you get home you should put some water in and rinse out the inside, so don't worry about water in there, just make sure you rinse it out with enough fresh water to clean it out.

 

[theskull]

Small amount of water entering is pretty much standard. A lot of water in the BC means you are trying to dump air when there is no air to dump--or at least no air at that access point, such as being vertically head up and opening your bottom dump valve when the air is all rising into the shoulder area.

There is a good chance that you need to add a couple pounds to your weighting as well, at least until you learn to relax enough to exhale ALL the air out of your lungs when it is time to descend.

Go diving often, especially with some folks who are more experienced than you.

theskull

 

[MyDiveLog]

I dive a SeaQuest Balance and don't seem to have that problem. Aside from the other recommendations (raise your left shoulder, remember to stretch the dump hose, etc.) try using your right rear dump when you get to depth. Assuming you descend head up, once you turn horizontal in the water the tips of the wings will be the highest point of the BC. I always seem able to "burp" the last little bit of air out that way.

Good luck & let us know how it works.

 

[herman]

MDL, in addition to having the dump at the highest point, assuming you are using your inflator hose, it has to be straight up as well. It's real common to see people hold the hose up but still have it connected somewhere on the shoulder strap of the BC so it is actually forming a large U shape which will not allow all of the air to be vented from the BC.

When using rear dumps, you have to consider the air movement inside the BC. Most BC bladders are inverted U shaped so if you just go head down and open the dump, you are only dumping one side of the bladder. To dump everything using a rear dump, you have to do sort of a side roll to get the air to one side of the bladder and then roll forward to get it to move to the rear of the BC before deflating using the rear valve.

 

[herman]

Ronnie, in addition to having the dump at the highest point, assuming you are using your inflator hose, it has to be straight up as well. It's real common to see people hold the hose up but still have it connected somewhere on the shoulder strap of the BC so it is actually forming a large U shape which will not allow all of the air to be vented from the BC.

When using rear dumps, you have to consider the air movement inside the BC. Most BC bladders are inverted U shaped so if you just go head down and open the dump, you are only dumping one side of the bladder. To dump everything using a rear dump, you have to do sort of a side roll to get the air to one side of the bladder and then roll forward to get it to move to the rear of the BC before deflating using the rear valve.