What's My Problem ?

[pat]

<font color='#0000FF'>I purchased new membrane suit and wolley bear to replace neoprene dry suit. &nbsp;On first dive I had a problem descending so I added some more weight &amp; ankle weights. &nbsp;30 minute dive at 18 meters with single 12l tank, my buoyancy was ok and I didn't add a lot of air to suit. &nbsp;Started to accend without shotline got to 12 meters and took off on rapid accent - repeated pressing of dump valve on shoulder had no effect - Pretty scary &amp; dented my confidence - any info greatly appreciated

Pat

[daz]

<font color='#000080'>Pat,

Did you put any air in your jacket at all ?
Did you notice if any air was coming out of the dump valve. &nbsp;It maybe that your undersuit is getting pulled unto the dump valve and blocking it slightly. &nbsp;You could try taping the undersuit down at the top of your arm.

Is it possible that either your weight belt, jacket is causing air to get trapped in the lower parts of the suit ?

I would recommend playing around with your suit for a good few dives in the shallow (10m or less) until your confidence is regained with the suit.

Daz

[pat]

<font color='#0000FF'>I didn't add any air to jacket at all. After dive Buddy suggested adding mimimum amount to suit and using jacket for buoyancy control - will try that next time. &nbsp;

Thanks for advice re taping down undersuit &amp; I will certainly be doing shallow dives until I get problem sorted.

Cheers

Pat

[dave archer]

Check you don't have a leaky suit inflator also - had this a while ago, kept dribbling air into my suit and consequently found myself getting more and more positive, dump dump dump.... (and I theorise same could hapen on BCD but not had that myself)
ATB
Dave

[Dr Stevil]

<font color='#0000FF'>I find the dump valve on my membrane to be a PITA at times, you can also try moving your arm in a &quot;punching the air&quot; type movement which helps to dislodge an undersuit/valve blockage, I often have to do this on dives, thinking of trying a different valve type (Si-tech) to see if its a design flaw.
TBH I think dumps valves are better on the wrist than the shoulder (where my current one is)
Chee-az
Steve

[Dominic]

What &quot;woolly bear&quot; are you using? Some are more liable to clog than others.

Rather than using tape, you could try those elasticated tube bandages they sell in 1st aid places - bit more flexible, does the same job.

I'm an advocate of not using the suit for buoyancy myself, keeping as little air as possible in your suit makes it easier to manage. Depending on how much weight you added, the problem could be that you were over-weighted and had too much air in your suit, OR that you were under-weighted and your cylinder, when empty after the dive, was enough lighter that you couldn't stay neutral.

Check the positioning of the dump - if it's set too low, you'll have dump problems. Also make sure you know which way to turn it without looking/experimenting - you wouldn't be the first person who'd closed his dump instead of opening it (My first dive with an autodump, and there I was at 35, narcosis buzzing around, and wondering how the hell I made sure my dump was open or closed...)

[daz]

Originally Posted by [b

Quote[/b] (Steve W @ June 18 2003,13:50)]I find the dump valve on my membrane to be a PITA at times, you can also try moving your arm in a &quot;punching the air&quot; type movement which helps to dislodge an undersuit/valve blockage,

<font color='#000080'>Mental note to self....

If diving with Steve avoid positioning self close to and above his left arm &nbsp;

[Finless]

Originally Posted by [b

Quote[/b] (daz @ June 18 2003,13:54)]Mental note to self....

If diving with Steve avoid positioning self close to and above his left arm  

If you hear the word &quot;duck&quot; don't start looking for water fowl.

[Mark Davies]

<font color='#000080'>The point made by Dominic was the one I first thought of.

I've made exactly the same mistake when I got my current suit and found the autodump didn't work the same as the previous one and I'd had it locked closed.

[Violent Ken]

Is it regarded as bad diving practice to use your BC/Wing to control buoyancy when diving with a drysuit, rather than the drysuit itself?

I've just acquired a drysuit and will spend some time getting used to it at about 6m, but I've never liked the sound of using it for buoyancy control as I've heard of a few people having runaway ascents. Luckily they were all on no-deco dives, but it's still a scary thought.