new second stage recommendations

[baggins_69]

I have a Mares MR-22 Abyss reg set (pre ruby), about 20 years old and recently the second stage has been constantly dribbling air rather than shutting off airflow when I'm not inhaling.

I've had it serviced 3 times including a complete rebuild and it is still happening (although not as badly). I am assuming there must be some corrosion or roughness in the valve body that is damaging the o-rings.

thinking it is time for a new second stage (and a matching octo while I am at it as my octo is a 40 year old sherwood magnum primary)...

I would like both effort adjustment and a shutoff valve on both

Thoughts on the HOG Zenith, DGX XTRA and Deep6 Signature and Excursion models?

something else I should be looking at?

not really looking to replace the first stage at this point although its time is coming and I would probably want to stick with whatever I get for the second stages, so I suppose if one of the related first stages is a deal killer, or particularly exceptional, that would be good to know too.

Thanks in advance!

 

[davehicks]

You need to make a close inspection of your 1st stage to be sure it's not related to your 2nd stage problems. If the IP of the 1st stage is high or drifting, then that could cause the 2nd stage problems you described. Do you have an IP gauge? If not, then buy one ($20 or so) and measure it.

Further, if you buy a 2nd stage only you will still need to tune the 1st and 2nd stages as a set or you may continue to have problems. The IP of the 1st stage will determine the spring tension needed for the 2nd stage to crack, breath, and seal smoothly.

As for what to pick, here is an article I wrote here on SB that goes over the features and attributes of regulators that might be important to you as you shop around. You'll be able to make a much more informed decision after you read this, unless you are already an expert.

Info - How to Choose a Regulator

How to Choose a Regulator (an overview of features and their value) One of the first pieces of equipment that every diver will acquire is a set of Regulators. This is one of the most critical pieces of your gear as it enables you to breathe underwater and are considered to be life safety...

scubaboard.com

 

[Nemrod]

There is not enough information here to diagnose the problem. The first stage IP could be set too high or could be creeping up. In either case and particularly the later the Mares second stage (which is not air balanced) would begin to free flow as you describe. If the first stage does lock up correctly and the IP is set to factory specifications and the second stage still dribbles air then it needs a new seat and a new volcano orifice and some tuning by a somebody who knows what they are doing (inferring the shop may not).

If the second stage were air balanced and the Abyss is not (and it is a fine regulator regardless) then there would be other things to look into like the air balance chamber O-ring in the second stage etc. But the Abyss is a simple seat and volcano orifice design. The Abyss first stage is designed to keep a very tight IP from full tank pressure to low tank pressure allowing fine tuning of the Abyss second stage to a very specific IP pressure set range.

If you want an excuse to buy new equipment go ahead but I would buy a complete set including first stage and two second stages. And then fix your older (problem) child and keep it around for spare.

James

 

[lowwall]

This is a really simple and robust second stage. It should have been pretty easy for a competent tech to find the problem.

As posted above, it could be a first stage problem. Hook up an IP gauge and see if the IP creeps up. If not, then let's look at the second stage.

Here's all the parts inside of your Abyss valve:

The most common cause of air dribbling would be a poor seal between the white part at left (the poppet) and the little black disk next to it (the poppet seat aka seat).

A new seat is included in Abyss service kits, but the poppet is not. If there's a nick or burr in the end of the poppet it should be replaced. The part only costs a few bucks, so I'd have put in a new one already.

Other possibilities include an issue with the o-ring that goes around the other end of the poppet from the seat, but that gets replaced at each service. I guess it's also possible there could be a scratch inside the metal part at top (the hose connector) where the poppet's o-ring sits that could let gas by.

I'd let another tech take a shot at it. Let's get @rsingler in on this. He specializes in troubleshooting regs that other techs can't or won't get running right

 

[lexvil]

As for the question on which second of those listed, whichever you find at the best price. Although as mentioned it may or may not help with the issue they are all good second stages.

 

[baggins_69]

ok, I ordered an IP pressure gauge. apparently the IP pressure is supposed to be 142-148psi so I'll check that.

at this point I don't have a lot of faith in my dive shop's regulator service guy, and apparently he is the guy for all the dive shops in the area, just goes to each shop on demand and batch processes their regs.

the first time there was some seaweed in the breathing chamber and so all he did was clean out the breathing chamber but didn't bother to even test it after because it was still blowing air.

brought it back, got a phone call "do you want a rebuild?" and I said if that is necessary to make it work right, then yes (made it sound like all they normally do is a function check), so it should have been a full rebuild.

still leaking (although not as much). this second has always been pretty aggressive in delivering air, always almost had to keep back pressure on it to keep it from free flowing when it got started..

 

[rx7diver]

... brought it back, got a phone call "do you want a rebuild?" and I said if that is necessary to make it work right, then yes (made it sound like all they normally do is a function check), so it should have been a full rebuild.

still leaking (although not as much). this second has always been pretty aggressive in delivering air, always almost had to keep back pressure on it to keep it from free flowing when it got started..

Did this tech have your complete regulator (the 1st stage + 2nd stage) when he rebuilt your 2nd stage?

rx7diver

 

[lowwall]

ok, I ordered an IP pressure gauge. apparently the IP pressure is supposed to be 142-148psi so I'll check that.

at this point I don't have a lot of faith in my dive shop's regulator service guy, and apparently he is the guy for all the dive shops in the area, just goes to each shop on demand and batch processes their regs.

the first time there was some seaweed in the breathing chamber and so all he did was clean out the breathing chamber but didn't bother to even test it after because it was still blowing air.

brought it back, got a phone call "do you want a rebuild?" and I said if that is necessary to make it work right, then yes (made it sound like all they normally do is a function check), so it should have been a full rebuild.

still leaking (although not as much). this second has always been pretty aggressive in delivering air, always almost had to keep back pressure on it to keep it from free flowing when it got started..

When you get your IP gauge, you can follow the guide here: Regulator Inspection and Checklist (Rev-8)

Step 10 covers use of the IP gauge, but it's all useful.

I have to wonder what your tech actually did for his "full rebuild". Was there a charge for a Mares second stage service kit part # 186160 or 46186160?

The service kit is mostly o-rings which he could have at hand, but it also includes a new seat. If the seat and poppet interface was the problem before, cleaning everything and swapping o-rings wouldn't solve anything.

An Abyss, with its all metal body has an essentially unlimited service life. Unless you really want a new reg, I'd send it off to someone who is really experienced with Mares regs for a proper service. Include a note with your issues. If ringler won't take it then maybe Scuba Regulator Repair - Scubatoys.com or https://lakehickoryscuba.com/

 

[Nemrod]

Remove the front cover and diaphragm if you know how. Does the second stage leak now?

If the lever is set to high it may be pushed by the diaphragm and purge button. There should be some give or free play when the purge is pressed before flow begins. Something like a 1/32 inch before the purge engages the lever and offset the seat.

James

 

[lowwall]

Remove the front cover and diaphragm if you know how. Does the second stage leak now?

If the lever is set to high it may be pushed by the diaphragm and purge button. There should be some give or free play when the purge is pressed before flow begins. Something like a 1/32 inch before the purge engages the lever and offset the seat.

James

You can check that the lever has that little bit of play without removing the cover. With the reg attached to a tank and the air turned on, shake the second stage back and forth. You should be able to hear a little "tick tick" from the lever hitting the diaphragm.

This post explains it really well: Mares Abyss Metal (42) cracking pressure adjustment

Note: the "orifice" referred to in that post is what I called the poppet. Mares has some unusual and inconsistent names for the internal reg parts.