Mares Abyss Cracking Pressure

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broadreach

Contributor
Messages
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Location
San Joaquin Valley, California
# of dives
200 - 499
I recently noticed that my Mares Abyss regulator is breathing a bit harder than I think it should, so I decided it would be a good time to test it. I ran through the checklist in the sticky thread and things seem fine. It passes the vacuum test, doesn't leak air and holds IP as expected. It also makes the rattle noise when pressurized (as expected) and keeps quiet when not pressurized.
When it came to the cracking pressure test however, I could not get it to crack. It reached the bottom of my 5 gallon bucket without releasing any air and as far deep as I could reach with my hand in the pool (without actually going into the pool). Breathing from it at the surface however, didn't seem THAT hard.

I know that the 'vortex tube' or whatever you call it is supposed to allow for easy breathing while preventing free flows. But is this normal behavior for this reg?

I believe that this model requires inline tools that I don't have to adjust cracking pressure and there's no Mares service center near me. I am planning a two day diving trip next weekend and I'm inclined to wait to ship it for service until I get back. Should I be concerned and line up a rental instead?

Thanks!
 
No need for an inline tool.......just an Allen key to adjust the orifice.
My preference would be to adjust so it doesn't rattle when pressurized.
 
The VAD helps once the reg has already cracked. It's a downstream design so cracking pressure .....may....not be.....quite.....as easy as a balanced job but I don't find any problem with my MR12+Navy which is a very similar design. You need to re-tune the 2nd stage. Read post #6 in this thread:
mares abyss mr22T 2010 small review with pics

Then go download the appropriate manual and read up. http://www.frogkick.dk/manuals/mares/

When you are doing the bucket-cracking test, once the mouthpiece starts to flood you have essentially failed the cracking test. Doesn't matter how deep into water a flooded 2nd stage goes, it ain't going to crack. It's the pressure differential created by trying to push the diaphragm underwater which pushes the lever, which opens the poppet. Either/both the lever and/or poppet need to be adjusted.

If that doesn't do it or you aren't completely comfortable with these procedures take it to a decent shop for tuning or an overhaul as appropriate.
 
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https://www.shearwater.com/products/swift/

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