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moosicman
11-05-2007, 08:04
I am presently going through certification and i know we are going to deal with this, but we haven't gotten that far just yet and so i wondered if someone would give us a bit of a definitive list of the reasons that you get free flow and the steps to avoid this. a free flow is one of the things i am a bit afraid of and this would sooth the timid little child within:)

Netsloth
11-05-2007, 08:18
There are a few common things that will cause free flow:

Water pressure on the purge button (because of current or entry, for instance)

Backup being too finely tuned (since it's not in use most of the time, it needs to be a little detuned)

Regulator orientation (mouthpiece pointed up can cause it)

Octo-cover that doesn't allow water into the mouthpiece (water on one side of the diaphragm, air on the other)

Thing to remember is that while it sounds really scary and loud when it happens, it's not hard to correct. Try blipping the purge valve, turning it mouth-piece down, putting fingers over the mouthpiece, flooding it with water if it's dry, etc.

I wear my backup on a neck-leash, and every once in a while, I'll get a freeflow on entry, but it's become second nature to reach up and right the orientation.

Don't let it stress you. If it becomes a constant problem, a quick adjustment by the tech should solve the issue.

Puffer Fish
11-05-2007, 08:42
There are a few common things that will cause free flow:

Water pressure on the purge button (because of current or entry, for instance)

Backup being too finely tuned (since it's not in use most of the time, it needs to be a little detuned)

Regulator orientation (mouthpiece pointed up can cause it)

Octo-cover that doesn't allow water into the mouthpiece (water on one side of the diaphragm, air on the other)

Thing to remember is that while it sounds really scary and loud when it happens, it's not hard to correct. Try blipping the purge valve, turning it mouth-piece down, putting fingers over the mouthpiece, flooding it with water if it's dry, etc.

I wear my backup on a neck-leash, and every once in a while, I'll get a freeflow on entry, but it's become second nature to reach up and right the orientation.

Don't let it stress you. If it becomes a constant problem, a quick adjustment by the tech should solve the issue.
I would be shocked if anyone diving any length of time has not had a bunch of them..Just makes a lot of big scary noise, while draining your tank. Looks worse from the outside than it is to the person. Netsloth is giving great advice. If something really brakes and that causes a freeflow, you can still breath from your reg, but it takes some skills you should learn in your class... and if you don't, then ask here, as I know there are several people that know this one by heart..

No Misses
11-05-2007, 09:04
I will add a little tidbit of information regarding freeflowing reg.

Here is a test for proper adjustment of a 2nd stage.
1. Fill your sink with 1 inch of water.
2. Slowly submerge your 2nd stage with the purge down/mouthpiece up. The reg should start to flow when the diaphram is ~1/2 below the surface. This is all the pressure differential that is needed to "open" the valve.

Now you can see that when you invert your octo under water (mouthpiece up) it should free flow. That is the way that they work. Note that this is with a reg out of your mouth. There is a slightly different dynamic when the reg is in your mouth. It all has to do with the pressure differential between the front of the diaphram and the back (where your mouth is).

Occasionally you may get a freeflow from the second stage that you are breathing from. This could be caused by salt crystals in the reg, improper tuning, etc.
1. Try exhaling forcefully
2. Tap the side of the reg.
3. If it continues to have trouble, abort the dive and slowly ascend. There is no reason to panic.

I hope this helped.

quasimoto
11-05-2007, 20:22
Another cause of free flow is cold water..45-50 or colder. If the first stage, basically ices up, it can cause a free flow. This happened at a quarry that I frequent earlier this year and two diver died. Never did figure out why.

Something that was kinda touched on but I don't feel was fully addressed is the draining your tank issue. Keep in mind that if the free flow goes on long enough then you will become lighter because of the air loss. With this happening you are going to ascend, maybe without knowing it. If you don't correct for it you could become a rocket to the surface. Remember that air expands as you ascend.

UCFKnightDiver
11-05-2007, 23:05
I have had my octo free flow while I was in my OW class, as in it wouldnt stop so the instructor hit it a couple of times and it stopped lol, I have heard this from several people, but didnt see it here, Someone tell me if this is a bad idea.

moosicman
11-06-2007, 09:46
That kinda fix makes me nervous...kinda like hitting the old black and white tv to help reception....I'm the type that wants to know "why" it was getting screwy so that i know what to fix....but just a "whop" and it is normal....that makes me wonder when its gonna go out and a "whop" won't fix it....just my 2 pennies....so if someone can answer this then i'll be more at ease as well

UCFKnightDiver
11-06-2007, 10:12
lol im kinda agrrein w/ you there moosicman someone please answer this im afraid hitting it will make it worse at some point but honestly dont have a clue

Tableleg
11-06-2007, 13:42
Diving Regulators (http://en.wikipedia.org/wiki/Diving_regulator) are not complicated devices though they are delicate. My guess is that on your particular octo just has a stuck valve opening arm and a few 'whops' just loosened it up. I'm guessing this was a rental and he (hopefully) check it out/ had it checked out once the class was over.

CompuDude
11-06-2007, 14:18
Diving Regulators (http://en.wikipedia.org/wiki/Diving_regulator) are not complicated devices though they are delicate. My guess is that on your particular octo just has a stuck valve opening arm and a few 'whops' just loosened it up. I'm guessing this was a rental and he (hopefully) check it out/ had it checked out once the class was over.

They're not that complicated, nor are they that delicate.

Whacking a reg a few times can help dislodge a piece of sand or salt crystals that is preventing things from sealing up properly. Equally effective can be shaking it vigorously underwater. While you shake, it will spew air like crazy. When you stop, and point the mouthpiece down, it should stop.

It's truly no big deal.

UCFKnightDiver
11-06-2007, 15:50
ok thanks guys and yes it was a rental, but no he did not check it out after the dive hmmm.

quasimoto
11-06-2007, 19:41
That kinda fix makes me nervous...kinda like hitting the old black and white tv to help reception....I'm the type that wants to know "why" it was getting screwy so that i know what to fix....but just a "whop" and it is normal....that makes me wonder when its gonna go out and a "whop" won't fix it....just my 2 pennies....so if someone can answer this then i'll be more at ease as well

I think you are worried about something that is probably not going to happen and if it does then it isn't that big of a deal. As for knowing how to fix it, think about the equipment specialist course. Most instructors will give you some tips on field repairs and what to look for.

Dive-aholic
11-07-2007, 14:42
Rentals tend to get abused. Your free flow simply means the reg probably needs a little bit of adjustment. The "whop" was a temporary adjustment. The reg should probably be checked out by a service tech and the IP tuned down a little.

As for regular free flows, I've had that happen. Sometimes the reg hits the water at the wrong angle and causes the valve to open just enough to free flow. Once you have 130-140 psi of pressure hitting the valve, it will stay open until you "whop" it or turn it mouthpiece down in the water. You actually don't even need to "whop" it. You can't just tap the purge button and that should stop the free flow. I've had a regulator free flow on me during a dive. It was the reg on a stage bottle, I had dropped on the bottom before the dive. Some sand apparently got in the 2nd stage and the thing kept sticking open. I had to close the tank valve a couple times to get it to stop because the "whop" wouldn't work.

Think about it, though, isn't it better that regs free flow rather than not opening and giving you air? It will take several minutes for the air in an 80 to completely empty out. (I VIP my own tanks and am emptying tanks several times a year.) You will have enough air to get to the surface if your reg begins to free flow. However, it's not likely to begin free flowing during the dive. The most likely time is before the dive.

Your instructor should be explaining all this to you.

Anne Eastwell
11-07-2007, 20:46
I had both my brand new regs freeflowing slowly on my first dive with them, more annoying than worrying. Nothing me or my DB did would stop either, it was like a slow leak.

The worst thing it did for me was chew through my air more than I would normally have done.

They got sent back to the supplier for a check-up and service (at no cost to me). just waiting to get them back now.