How it's a spg problem, when the same spg works on another 1st stage, and other spg's doesn't work on the 1st stage with the issue? It is a 1st stage issue.. of what kind, I don't know.
(I specified it in my previous posts)
Circuit under pressure with tank closed after purging
- Thread starter npole
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How it's a spg problem, when the same spg works on another 1st stage, and other spg's doesn't work on the 1st stage with the issue? It is a 1st stage issue.. of what kind, I don't know.
(I specified it in my previous posts)
Maybe there is debris in the 1st stage.
halocline
Contributor
I'm still not sure exactly what you're talking about, but if I understand:
1. You pressurize the regulator.
2. The SPG (any SPG) does not register tank pressure. Instead, it either stays at zero or rises only a little.
3. You purge the 2nd stage a few times.
4. Then the SPG does register tank pressure.
5. You de-pressurize the regulator by turning off the valve and purging.
6. Does the SPG drop to zero smoothly or does it 'stick' at tank pressure?
When you remove the SPG hose from the 1st stage, you hear air escaping that indicates there is still some pressure in the regulator, correct? This is after removing it from the tank.
Or does the SPG go right to tank pressure when you pressurize, then drop to zero when you depressurize, apparently working fine. The only problem is a bit of residual pressure in the SPG after turning off the tank valve?
1. You pressurize the regulator.
2. The SPG (any SPG) does not register tank pressure. Instead, it either stays at zero or rises only a little.
3. You purge the 2nd stage a few times.
4. Then the SPG does register tank pressure.
5. You de-pressurize the regulator by turning off the valve and purging.
6. Does the SPG drop to zero smoothly or does it 'stick' at tank pressure?
When you remove the SPG hose from the 1st stage, you hear air escaping that indicates there is still some pressure in the regulator, correct? This is after removing it from the tank.
Or does the SPG go right to tank pressure when you pressurize, then drop to zero when you depressurize, apparently working fine. The only problem is a bit of residual pressure in the SPG after turning off the tank valve?
1. Yes, opening the tank.
2. Correct, either zero or like 100bar when the tank is really at 200bar.
3-4. Yes, closing the tank, purging, sometime removing the whole 1st stage from the valve and reconnecting, after some apparently random procedure, it finally register the pressure and the spg works flawless... until the next dive with a new tank, where I have to repeat the above procedure;
5. Yes, and by uninstalling the whole first stage;
6. After have closed the valve and purged the regulator, the spg goes to zero as expected;
After removing the spg (and the hose) from the 1st stage you can hear some residual air inside the circuit escaping from the HP port. I think this behavior is normal, whenever the guy that have checked the regulator said that it indicates some sort of issue.
In my opinion the HP chamber got dirty or something like this, whenever the regular should be sealed (MK17), maybe some tank dust or residue got stuck in the HP chamber and it's causing this issue. Maybe sometime it works by closing/opening the valve, because the pressure moves the dirt stuff around.
It's a strange thing really, I believed that an spg would just work by the air pressure pushing the internal mechanism, so it would show the real pressure or nothing at all (if the HP port is obstructed), how it would report half of the real pressure considering that the spg is not malfunctioning (as we tested with different spg's and different hoses).
2. Correct, either zero or like 100bar when the tank is really at 200bar.
3-4. Yes, closing the tank, purging, sometime removing the whole 1st stage from the valve and reconnecting, after some apparently random procedure, it finally register the pressure and the spg works flawless... until the next dive with a new tank, where I have to repeat the above procedure;
5. Yes, and by uninstalling the whole first stage;
6. After have closed the valve and purged the regulator, the spg goes to zero as expected;
After removing the spg (and the hose) from the 1st stage you can hear some residual air inside the circuit escaping from the HP port. I think this behavior is normal, whenever the guy that have checked the regulator said that it indicates some sort of issue.
In my opinion the HP chamber got dirty or something like this, whenever the regular should be sealed (MK17), maybe some tank dust or residue got stuck in the HP chamber and it's causing this issue. Maybe sometime it works by closing/opening the valve, because the pressure moves the dirt stuff around.
It's a strange thing really, I believed that an spg would just work by the air pressure pushing the internal mechanism, so it would show the real pressure or nothing at all (if the HP port is obstructed), how it would report half of the real pressure considering that the spg is not malfunctioning (as we tested with different spg's and different hoses).
CuzzA
Wetwork for Hire
АлександрД
Contributor
American components, Russian components.... ALL MADE IN TAIWAN!
Brother, my apologies. I couldn't stop myself.
Most SPG use gear mechanizm
Any gear (exclude special, contains two wheels and spring) has back lash (play).
Little shock can help make small move to the details
It could be, if SPG was leaked a little, and gears oxidized.
Also your description of SPG+1st behaviour looks like your 1st has very small hole, and may be obstructed by particles.
Try to connect 1st to the tank WITHOUT HP hose!
open tank, wait a little, and it could be cleaned by air.
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Also your description of SPG+1st behaviour looks like your 1st has very small hole, and may be obstructed by particles.
Try to connect 1st to the tank WITHOUT HP hose!
The first stage has two HP ports... both ports are affected, it's not the air exit hole, it's inside the chamber (or whatever it is).
АлександрД
Contributor
sorry, small offtopic, but in theme:
A lover comes to the wife and says:
- Let's undress, I came up with a new pose, we will experiment.
- I can not, my husband bought a talking parrot, he will tell everything.
- Do not worry, we'll cover the cage - nothing will see. You get up at the table, bend forward, and I'll climb on the chandelier, swing, and everything will be as it should be.
Suddenly a rabid roar from the cage:
"Tear out my tongue, but I have to see it!"
As my instructor and friend talking - "there is small gnomes inside...."
A lover comes to the wife and says:
- Let's undress, I came up with a new pose, we will experiment.
- I can not, my husband bought a talking parrot, he will tell everything.
- Do not worry, we'll cover the cage - nothing will see. You get up at the table, bend forward, and I'll climb on the chandelier, swing, and everything will be as it should be.
Suddenly a rabid roar from the cage:
"Tear out my tongue, but I have to see it!"
As my instructor and friend talking - "there is small gnomes inside...."
halocline
Contributor
The only thing I can think of is some obstruction in the passage between the HP chamber and the HP ports. It's got to be something really small that moves around a bit and gets wedged in place. You could try cleaning it out. I might start that process by making a HP transfer whip out of an existing HP hose and a few fittings, (Couv posted something about this a while back) then connect the HP ports on this 1st stage to another one. Take the filter out of the clogged 1st stage, attach the other one to a tank, and open the valve. This way you're blowing HP air in the HP port, and out the inlet. Do each HP port. You might get lucky.
When that doesn't work, you can try to insert some very fine wire in each HP port and try to clean it that way, or try some sort of hydraulic thing where you fill the HP chamber with water or vinegar, then try to pressurize it with the LP ports plugged and the HP ports open.
This is all a guess on my part.
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