Free flow 2nd Stage

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DDI

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Location
Melbourne Australia
# of dives
I just don't log dives
Free flowing 2nd stage when the adjustment knob is turned up past 1/2 way. Any simple fix?:)
 
first of all are you talking about your primary or auxiliary regulator if you are talking auxiliary then my instructors say have that one at the top of plus side .it breathes harder but its only used for emergencies mainly and once in your mouth it can be adjusted .i had mine stick twice in cold water dives leaving it in the middle once adjusted up all the way no more problems
 
Check the IP of the 1st stage first. If the 1st stage is the culprit then there is no simple fix.
 
Thanks Centrals, I haven't got my IP gauge with me but I will test it asap. If the IP is ok eg 8-10 bar 150psi etc. what else could be adjusted? Although I have a suspicion you are heading in the right direction.
 
What reg is it?
Assuming you have a balanced adjustable of some type: when properly adjusted, the knob will be all the way out and there will be a slight leak, not a hiss. Then turn the knob in a 1/4 turn or so and it should stop.
Further adjustment maybe needed during dive if it burps air.
When checking for IP with your IP gauge, you are not only looking for what pressure, but if there is creep. Meaning if it starts at xxx psi then moves higher, which will cause the free flow.
Your Low Pressure seat may scored deep as well.
When was the last service? Do you play with the 2nd stage knob?
 
1) You could take it to the LDS, because they serviced it and still needs adjustment or because it need a service...

2) don't turn the nob past 1/2 way

3) Have a go at adjusting. Take the LP hose off and inside will be the orifice. Turn it clockwise say a 12th turn. Some say you should press the purge button when you turn the orifice so you do not risk cutting the seat. Put the LP hose back on and see how it is. The balance control is the fine tune the orifice is course.

Was this reg serviced recently? The seat is 'setting'.
 
You don't specify what regulator model you're using. 145psi is a bit high for all the ones I'm familiar with, but not disastrously so.

Most likely you need to adjust the spring pretension on the second stage. Depending on your regulator model there are different ways of doing this. The recommended way of knowing you've got it right is to use a Magnahelic gauge to check the cracking effort You can guestimate by just breathing on the regulator, but you might have to make some adjustments after a test dive.

Few points:
-With the adjustment knob all the way on the easiest-to-breath setting and the regulator sitting on the table in front of you it should NOT have a slight leak. It should just be sitting there.
-If you take the LP hose off and turn the orifice you will increase the pretension on the spring. However, without knowing what regulator model you have I would not recommend doing this just yet. In most regulators this will cause the demand lever to drop away from the diaphragm (you can verify this by shaking the regulator and listening for a rattling noise). This can cause your purge button to malfunction which is a safety issue.
- On some regulators the orifice adjustment is used primarily to set the demand lever height with an adjustment screw on the opposite side of the regulator for adjusting the cracking effort (what you want to modify). Others use the orifice adjustment primarily to set the cracking effort and a screw on the opposite side to set the lever height. So how you tackle this depends on what regulator you have.
-In your test dive you should be able to float in pretty much any position and not have a free flow with the regulator on the easiest-to-breath setting. The exception is possibly with your head straight down. When you breath in any of these positions the regulator should stop delivering air when you stop inhaling. If it continues to flow after you stop breathing in (you'll get bubbles out the exhaust valve) then you need to increase the cracking effort.
 
No idea what brand of reg the OP was talking.
I use Apeks reg and 10 bar is slightly over the recommended range but it should not normally cause any free flow. If the IP of my Apeks 1st stage is 10 bar and with a slight free flowing 2nd stage then I will definitely service the whole set. The rubber seat on the 2nd stage probably need to be replaced.
So it won't be simple fix, it is a complete overhaul.
 
https://www.shearwater.com/products/peregrine/

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