IP Question - Mares MR22

[Zef]

I just got a deluxe IP gauge from DGX. Tested my two older MR22 Abyss 1st stages and found the IP was high:
One was reading 150psi and the other 155psi.

The specs from Mares is 142-148psi

I adjusted the first stage by loosening the regulating nut with a 10mm Allen key.

When purging one of the 2nd stages the IP will drop and then the needle will indicate between 140 and 145 and then over a couple of seconds it will arrive at just below 150 (148?) and stop. The gauge markings are in 10psi increments.

I left the regulator pressurized with the IP gauge attached for about 10 minutes and did not observe any further change. The IP gauge behaves similarly on both 1st stages.

Since I am new to using an IP gauge and reg maintenance, is it safe to assume this is normal behavior for the older MR22 Abyss 1st stages or should I consider there is a problem and rebuild them?

-Z

 

[Jcp2]

I think the drop on IP when purging happens with most regulators. I am for mine to be within the specified range in the no flow state.

 

[James79]

The drop when purging is normal. The couple of seconds to lock up after releasing the purge is your concern, correct?
I assume the usual suspects with more experience than I will chime in soon. In my (limited) experience, what you describe is no big deal. If IP continued to creep up, that would be a cause for concern. I would just make a note of it and watch that it doesn't get noticeably worse.
Respectfully,
James

 

[Zef]

I think the drop on IP when purging happens with most regulators. I am for mine to be within the specified range in the no flow state.

The drop when purging is normal. The couple of seconds to lock up after releasing the purge is your concern, correct?
I assume the usual suspects with more experience than I will chime in soon. In my (limited) experience, what you describe is no big deal. If IP continued to creep up, that would be a cause for concern. I would just make a note of it and watch that it doesn't get noticeably worse.
Respectfully,
James

Correct, I totally understand the IP drop on purging/breathing off the 2nd stage is normal. The concern is time it takes to "lock up".

I checked for creep by leaving the system charged with the IP gauge attached and rechecked after 5 minutes, and again after 10 minutes for each of my 1st stages and there was no further movement of the needle that I detected after it settled at 148psi.

-Z

 

[rhwestfall]

While I have no specific familiarity with that regulator, slow but solid lock-up is not really a problem from my experience.

 

[James79]

Correct, I totally understand the IP drop on purging/breathing off the 2nd stage is normal. The concern is time it takes to "lock up".

I checked for creep by leaving the system charged with the IP gauge attached and rechecked after 5 minutes, and again after 10 minutes for each of my 1st stages and there was no further movement of the needle that I detected after it settled at 148psi.

-Z

Speculation here, but I suspect that there is a very minor imperfection on the sealing surface (either edge of volcano orifice or on the HP seat material). Resulting in it being "set" for 143-ish IP, but a tiny trickle getting through the imperfect seal until, at 148 IP, the seat is compressed enough to fill in and close the imperfection.
So, as long as it is consistent, no harm-no foul. Check it periodically and rebuild when it starts mis-behaving (like IP creep... Where it doesn't stop), or needs a super thorough cleaning (like known water intrusion).
Of course, my advice is worth what you paid for it! Lol.
Respectfully,
James

 

[Open Ocean Diver]

My Atomic T3, with an IP of 150 will hiss.

 

[runsongas]

the behavior you are seeing is relatively normal. it is just a slightly mushy lockup. can try to magic mesh the orifice to see if it improves slightly.

 

[JahJahwarrior]

I wouldn't worry about it at all. In recreational diving, you are breathing off that regulator the entire dive, so as long as it's not getting too high between breaths, the only other concern would be the time from turning on your valve to getting in the water. Yours is locking up nicely, just delayed, so not a big deal. I would not consider touching it until next service, at which point you can polish the orifice with a pencil eraser for just a moment, but it's probably nothing.