Slight free flow.

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MaxE

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Location
New Orleans, La (below sea level)
I have some atomic regulators that have been driving me crazy. The primary 2nd stage continues to have a slight free flow issue. I’ll de tune it till it goes away and it comes back. Last dive the secondary second stage also started to bubble bubble. The IP starts at 120 and creeps up to just below 130 and seems to hold there. Last service it was recorded at 125. What am I missing? Do I love the way they breath, so easy. Do I need to detune like 1/2 a turn? I feel this will have an impact on breathing.
 
Does the IP creep up until the 2nd stage freeflows?
 
the lockup should not be that mushy. how long has it been since it was serviced?
 
Does the IP creep up until the 2nd stage freeflows?
No, it seems to lock up. But I feel if I take strip in a week it will be flown by the end of it. It’s very slight, very slow bubbling like between a breath in and out I a few bubbles from the exhaust. I can adjust it away with the know on the 2nd stage but feel I should be able to get it to hold with out doing that
 
Sounds like a slight first stage leak to me. A tiny leak in the first stage will show up as a slow IP creep until one of the second stages starts to flow just enough to compensate for the leak. If you detune the second stages and the IP creeps up to a higher value, it's def a first stage leak......my guess is a tiny ding on the lip of the piston, a common problem with piston regs.
 
Sounds like a slight first stage leak to me. A tiny leak in the first stage will show up as a slow IP creep until one of the second stages starts to flow just enough to compensate for the leak. If you detune the second stages and the IP creeps up to a higher value, it's def a first stage leak......my guess is a tiny ding on the lip of the piston, a common problem with piston regs.
Very possible but the piston was replaced/upgraded at the last service and I have not seen the IP go above what was recorded last service. Is there any reason that the increased pressure under water would be factoring into this? It’s one variable I can’t reproduce
 
Not likely being UW has any effect on this. The fact that the piston was replaced actually makes it more suspect, it's not the first time a good part has been replaced with a bad one. If you have a IP gauge remove the second stages, plug the holes and SLOWLY crack open the valve carefully watching the IP, my guess is it will go way high....just be sure to cut off the valve before it gets too high. It would be easy for a less than careful tech to miss this and assume since the the IP "stopped" it was good when in reality, the second stage was leaking enough to stop the increase any farther.

One more test you can do UW is to detune one stage a good bit, breath off of it and watch the other one. If it's an IP leak, the unused (and lighter tuned) second stage will start to dribble air in a few seconds after you take a breath. Take another breath and watch the bubbles from the other second. they will stop for a little while, depending on how much leak you have, it may take a few to a number of seconds before it starts to dribble air again. If it starts again, dead give away the first is leaking.
 
Not likely being UW has any effect on this. The fact that the piston was replaced actually makes it more suspect, it's not the first time a good part has been replaced with a bad one. If you have a IP gauge remove the second stages, plug the holes and SLOWLY crack open the valve carefully watching the IP, my guess is it will go way high....just be sure to cut off the valve before it gets too high. It would be easy for a less than careful tech to miss this and assume since the the IP "stopped" it was good when in reality, the second stage was leaking enough to stop the increase any farther.

One more test you can do UW is to detune one stage a good bit, breath off of it and watch the other one. If it's an IP leak, the unused (and lighter tuned) second stage will start to dribble air in a few seconds after you take a breath. Take another breath and watch the bubbles from the other second. they will stop for a little while, depending on how much leak you have, it may take a few to a number of seconds before it starts to dribble air again. If it starts again, dead give away the first is leaking.
Thank you this is super helpful. Before I remove and plug the 1st stage if you are correct I should be able to see the 2nd stages leaking if they are submerged correct? If they don’t leak and IP is holding than it’s something else? Improperly tuned 2nd stages? Is there a likely good that bouncing in the back of my car and out to a dive is enough to move them from where they were set? I can’t imagine how.
 
Do I need to detune like 1/2 a turn?

Which stage do you intend to detune? What is the position of the 2nd stage in the water, mouthpiece up, mouthpiece down?
 
https://www.shearwater.com/products/perdix-ai/

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