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Bryanmc
11-24-2007, 14:59
My pull dump seems awfully hard to pull. I'm not really sure how hard it should be. I took the inflator hose off and looked inside. It looks like at "full pull" it's only moving the valve about 1/8 - 1/4 inch max. I'm afraid I'm going to pull the grommet off the bladder. Is this normal or do I need to send it in?

Thanks

reservecops
11-24-2007, 17:54
It doesn't need to open as wide as the Grand Canyon.

Also, be sure that you're grasping the inflator when you pull, and not somewhere in the middle of the hose.

Bryanmc
11-24-2007, 18:08
I suppose it doesn't need to open all that wide, but 1/8" seems a bit short. I do grab it at the inflator when I dump it.... I've seen some folks say theirs were so sensative they would dump when they grabbed the inflator. Doesn't seem like it's right if it feels like I might rip it off the bladder...

marchand
11-24-2007, 19:18
your hose is probably one of those corrugated looking ones but not really. I bet if you look inside you will see that it is a flat hose. these really don't stretch all that much.

if not it might be that the steel cable is to long. how much is the hose stretching?

Splitlip
11-24-2007, 19:52
Is it not dumping gas adequately?

I think that is the question to ask

tedwhiteva
11-24-2007, 20:00
Is it not dumping gas adequately?

I think that is the question to ask

Another is why are you using the pull dump?:smiley13:

marchand
11-24-2007, 20:06
Is it not dumping gas adequately?

I think that is the question to ask

I think the problem is that he has to pull on it quite forcefully for it to dump adequately. Am I right?

bperrybap
11-24-2007, 22:48
I had the same problem until I replaced the "corrugated" hose with
a real corrugated hose.
The problem I had was definitely related to the "corrugated" hose.
See this thread on SB: Zeagle Ranger Pull Dump Question (http://www.scubaboard.com/forums/buoyancy-compensators-bc-s-weight-systems/196233-zeagle-ranger-pull-dump-question.html)
See my post (#5).
The newer hoses are much stiffer than the old ones.
While more rugged, they simply don't stretch as well/easy as the early ones.
If you don't feel like going through the hassle of replacing it, you
can try pulling on the hose with the hose/inflator away from your body rather
than pulling down on the hose with it close to your body.
This should reduce the necessary amount of force quite a bit as
it reduces the pull distance necessary to open the valve.

To try this, you don't even have to dive the BC. Simply put the BC on
and fully inflate it orally. Then try pulling on the hose. You should notice
that it takes less force to dump air if you pull on the hose outward or
even up rather than pulling down with the inflator near your body.


--- bill

Bryanmc
11-25-2007, 10:12
Is it not dumping gas adequately?

I think that is the question to ask

To be honest, the first time I dove it I don't think it dumped at all. That was before I realized how hard I had to pull it. My knighthawk dumps gas fairly easily. After I learned how much force it took I can get it to dump but I'm not comfortable pulling on any piece of equipment that hard, especially not one held together with a plastic zip tie that will be a real a problem if it comes apart at depth.

As far as dumping adequately, dumping all the gas is a 3 move event... pull the inflator dump while dropping my right shoulder, once that's done flip head down... pull both bottom dumps. I'm amazed by how much gas dumps out the left bottom dump even after I've dumper the left shoulder.

As to "why are you using the inflator dump?" I suppose I could hold the hose up and push the button, but there's a pull dump for a reason.

I'm hoping Scott will have some ideas... If not this one will be for sale which is a shame because I really like it overall.

Bryanmc
11-25-2007, 10:26
If you don't feel like going through the hassle of replacing it, you
can try pulling on the hose with the hose/inflator away from your body rather than pulling down on the hose with it close to your body.
This should reduce the necessary amount of force quite a bit as
it reduces the pull distance necessary to open the valve.
--- bill

I was doing the testing with the assembely removed from the bc. It didn't seem to open any more or less. As I said earlier, if I look into the elbow while pulling the inflator, a gap of about 1/8" opens where the valve seats. Doesn't seem like a big enough orofice to dump air efficiently, and it still takes serious effort. Maybe some folks could look at thiers and see how far it opens.

marchand
11-25-2007, 11:45
mine opens about a half inch.

your hose might not be a true corrugated hose. If the grooves in it are square then it isn't and a new hose that is actually corrugated. if it is a good hose then it might be that the spring is to stiff.

Bryanmc
11-25-2007, 12:32
It is the square type ridge. I can't be the only person having this problem unless the cable is too long or something. I'm really not wanting to re-engineer a brand new bc :smiley5:

Bryanmc
11-25-2007, 14:07
Here are some images to help explain.....

http://i236.photobucket.com/albums/ff155/bryanmc/th_dump-open2.jpg (http://i236.photobucket.com/albums/ff155/bryanmc/dump-open2.jpg)
http://i236.photobucket.com/albums/ff155/bryanmc/th_dump-open1.jpg (http://i236.photobucket.com/albums/ff155/bryanmc/dump-open1.jpg)
http://i236.photobucket.com/albums/ff155/bryanmc/th_dump-closed.jpg (http://i236.photobucket.com/albums/ff155/bryanmc/dump-closed.jpg)

The top 2 are the valve open, the bottom is the valve closed. Sorry it's hard to make out.

bperrybap
11-25-2007, 16:17
I was doing the testing with the assembely removed from the bc. It didn't seem to open any more or less. As I said earlier, if I look into the elbow while pulling the inflator, a gap of about 1/8" opens where the valve seats. Doesn't seem like a big enough orofice to dump air efficiently, and it still takes serious effort. Maybe some folks could look at thiers and see how far it opens.

Try testing it hooked up. The amount the spring mechanism moves
shouldn't be the issue.
It takes very little movement to fully open the valve.
Mine only moves about 3/16".
The dumping occurs by relieving the pressure on a seal on the flapper valve
which is about 1" in diameter.
Once the pressure is relieved on the o-ring that seals this flapper valve,
you basically have a 1 inch hole venting air and the air dumps quite rapidly.

The issue you are having seems exactly like what I was seeing.
I spent quite a bit of time figuring out what was causing this.
The problem is getting enough movement on the wire inside the dump
hose to move the spring mechanism.
The newer hoses aren't as stretchy as the older hoses so it takes more
effort/force to get the same amount of movement.

What compounds the problem is where the dump valve lands on your back.
The lower it lands, the shorter the amount of hose on the front side
of your shoulder. When you pull down on the hose, the only part of the hose
that will stretch is the part on the front side of your shoulder.
This is because the top of your shoulder kind of "grabs" the hose and
so hose from the top of your shoulder to the dump valve doesn't see
any force and doesn't stretch. The remaining part of the hose has to
do all the stretching and with the newer less flexible hose, it takes
a lot of force to get enough stretch to move the cable enough to
operate the dump.


Also, when the hose is curved (like over your shoulder when pulling down),
the curve/bend radius of the cable inside the hose is less/smaller than the
curve radius of the hose itself. This means that the more you bend the
hose, the hose in relationship to the wire will be shortening more than the wire.
This effectively means that the wire gets longer as you bend the hose and
requires more hose stretch to get the same amount of wire movement.

The smaller your shoulder is, the tighter the radius, which means
the effect is more pronounced for people with smaller/narrower shoulders.

To see this effect, fully disconnect your inflator from the hose. You will
see a dump cable inside the hose.
Now bend the hose. Coil up the hose, the cable will now start to get
"longer" and will be several inches longer than the hose and hang out the
end of it.
This is what happens when the hose is draped over your shoulder.
The cable gets "longer" which means that you need more stretch to
get the same amount of cable movement on the dump valve when the
hose is draped over your shoulder (curved) vs being straight.


-----------------------------


So what I saw, is the combination of the newer less stretchy hose,
combined with where the dump valves lands on your body, and
the shape of the shoulders, can create a situation where the dump valve will
not operate at all when pulling down on it. This is what was happening to me.
No amount of downward force would operate the valve.
However, it would operate if I pulled away from my body. At 30-45 degrees
away from my body it started to work and it operated quite easily if I pulled
"up" on it. This is because by changing the angle of pulling, it was removing
the bend radius as well as allowing the entire hose to stretch.

So while I could make it work by not using the velcro holder on the hose
and pulling the hose away from my body or up,
I got tired of having to do that, so I replaced the hose with the older more
stretchy version and now it works just fine all the time regardless of position
and with a lot less force as well.

--- bill

marchand
11-26-2007, 22:50
you just need to get a new hose.

awap
11-27-2007, 08:31
When I first went from a Seaquest BCD to a Diverite wing (looks like the same pull dump mechanism as yours) I had the same sensation. The SQ pull dump jused used a much lighter spring which allowed inadvertent dumping if the inflator was accidentally pulled a bit. I replaced my DR pull dump with a simple elbow when I abandoned my air2.

quasimoto
11-27-2007, 16:05
If all else fails send it back to Zeagle or return it to where you bought it. Zeagle WILL take care of it.

Bryanmc
11-27-2007, 18:09
Actually I sent a pm to Larry and asked him if he had any ideas (since they have countless hoses and such). He said just send it in and they'll make it work and turn it around in one day. You really can't find better customer service than that!!!! He even offered to pay the shipping to get it there.

SCUBATOYS ROCKS!!! :smiley32:

ScottZeagle
11-28-2007, 08:37
We are looking at this issue now, from all sides.

We think that some of the cables inside the corrugated hoses are just a little too long, which is requiring extra pulling. These new hoses look a lot better than the old hoses, but they don't really stretch as easily, so having the cable the right length becomes more critical.

Thanks for all your input!!

Scott

Bryanmc
11-28-2007, 18:12
Thanks for weighing in Scott. I like the new more sturdy hose but not getting an upper body workout everytime I want to dump some gas. I'm sure you guys will have it fixed in no time.

rfreddo
12-14-2007, 09:18
We are looking at this issue now, from all sides.

We think that some of the cables inside the corrugated hoses are just a little too long, which is requiring extra pulling. These new hoses look a lot better than the old hoses, but they don't really stretch as easily, so having the cable the right length becomes more critical.

Thanks for all your input!!

Scott


Just wondering if there are any updates on a fix/suggested procedure.

Bryanmc
12-18-2007, 09:13
Sorry for taking so long posting the resolution to the problem. I got the new pull dump assembly from ST. The new hose does not hang completely straight, there is a very slight bend in it (not so much that you'd notice if you weren't looking for it). It appears the inner cable is a tad shorter than the original, so now all I have to do it straighten the hose out to get it to dump as opposed to trying to stretch a not so stretchy hose.

A thousand thanks to Larry, Scott, and the ST crew!!

rfreddo
01-09-2008, 10:05
We are looking at this issue now, from all sides.

We think that some of the cables inside the corrugated hoses are just a little too long, which is requiring extra pulling. These new hoses look a lot better than the old hoses, but they don't really stretch as easily, so having the cable the right length becomes more critical.

Thanks for all your input!!

Scott


Scott - Have there been any further developments on this? Is this something that might be handled as a recall, either for the hose or the cable?