Venting a BCD

[Bobyjimmie]

LOL yeah funny how air rises when underwater isnt it? Wonder if they wonder why they have loads of water in their BCD when they clean it at the end of the day.

 

[Aspendiver]

There seem to be a large number of divers who either weren't taught or dont remeber the lesson on using whatever dump is highest.

I've seen no end of divers slightly head down attempt to dump air by holding the button on the hose then looking confused when nothing happens and they continue rising faster and faster.
A few i spoke to have said they didn't realise you COULD use those other dumps underwater which is a bit disturbing.

Standardized training. EVERY BCD (well, late model) has an inflation hose. You can't assume that anything else is standard. Therefore, no training in their use...
Why do previous posters assume shoulder toggle? Mine doesn't.....
As to water entering the BC- my rear dumps fill my BC bladder much faster than the inflator hose does.
That doesn't preclude taking individual responsiblility for learning and understanding the function of your own equipment. If I just listened to some of the posters on this thread, I'd look pretty stupid yanking on my hose expecting something to happen.
:no

 

[Bobyjimmie]

How can your rear dumps let water in if your deflating through them and they are the high point of your BCD?? It is physically impossible, provided your using them correctly.

 

[String]

Provided there is air to come out water is unlikely to get in.
Most water found in jackets are either people trying to empty an already empty jacket or just using the wrong dump at the time.

As for assuming shoulder toggles, even without those its not an issue. My single wing has no hose pull or shoulder toggle. The lower one works quite effectively for me.

 

[Ed Palma]

When I was still using my old stab jacket, I would make use of the shoulder dumps. However, over time, I noted that if the rubber seal on the valve became grooved, pulling on the dumps would somehow dislodge the seat from its position, and allow a minute leak at the point where the groove would be.

And I also disagree with the notion that every modern BCD has inflation hoses. I don't recall seeing one in Mares HUB BCDs and their ilk. Then again its been a while since I actually saw one, so YMMV.

 

[Ed Palma]

You might need to add just a little more weight to compensate for the empty Alum tank... or see if you can find a steel one? As you use up the ALUM tank it gets lighter.

I'd add just a little more weight.

I'd be wary as to adding more weight. Say, for example, he uses Al80s. If he used it till empty, they would be around +4 pounds (well, at least Catalina Al80s would be). Lets add another 2 pounds to compensate for being in salt water. That makes six pounds. I'd say that the buoyancy characteristics of a dive skin would require negligible weight to keep it down. Therefore, what would the remaining 12 pounds be for (remember, the OP dives with 18 pounds in a skin)?

To the OP: Have you performed a proper buoyancy check?

 

[String]

I don't recall seeing one in Mares HUB BCDs and their ilk. Then again its been a while since I actually saw one, so YMMV.

All the Mares "Airtrim" branded jackets have the same system - no hose and buttons on the lower left hand side. I think Seac or another brand that clones them also has the same.

 

[Nick_W]

And I also disagree with the notion that every modern BCD has inflation hoses. I don't recall seeing one in Mares HUB BCDs and their ilk. Then again its been a while since I actually saw one, so YMMV.

See, that's why I didn't say "all". I knew there would be someone out there who would know of a BC that didn't have it.

But the odds are pretty good that if you go on vacation and rent a BC, you're going to get one with an inflator hose. That's the point I was making.

 

[Aspendiver]

How can your rear dumps let water in if your deflating through them and they are the high point of your BCD?? It is physically impossible, provided your using them correctly.

So, you're a physicist, or an hydraulic engineer, and you can say that unequivocally?
I think its a good question, but it seems to be my experience.
I'm guessing here- but a couple of things come to mind. One, like String says, I may be trying to exhaust an already empty bladder, or at least, an empty side- my single horseshoe shaped back-inflate bladder has a pull tog at each end, and there can be air left on one side and not the other. Secondly, a pull-tog does not open symmetrically (it's just a spring loaded 2" disc on a string-if you don't pull it exactly perpendicular to the opening, it opens in a slit, not a perfect circle. Try it, if you don't believe me- I just did!), which, depending on my trim in the water, could produce an opening that might let water in around the air as it exhausts? I honestly don't know. I'm sure somebody else has an opinion?
I can't believe that not one person laughed at my hose joke.
So far, not one person has defended my basic premise, which is this- if you're horizontal, use your rear dumps. If your vertical, use your hose, and if pulling the velcro tab hose router helps empty the bladder, then do it! I guess I must be wrong.

 

[String]

But the odds are pretty good that if you go on vacation and rent a BC, you're going to get one with an inflator hose. That's the point I was making.

...and equally as likely to have a rear dump on the bottom and probably top as well.