Scubapro MK25 creep?

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uncfnp

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This Mk25 was serviced April 2015, was used for about 15 dives over the next 3 months and has been unused in my closet until I got it out in preparation for cenote dives next month. Checking the IP I got this...



I assume this is the infamous IP creep and indicates a HP seat going bad? I have a service kit so it isn't an issue but just wondering how common this is for a very lightly used regulator and is it bad enough to service now or just keep an eye on it. It does eventually lock at 153.
 
if it locks and stays at 153, then it is more IP drift than creep, but it does have to stop. What likely happened is the seat took a "set" and that "set" is causing the higher IP. @DA Aquamaster can better determine how much adjustment is in the top cap, but I suspect you'll have to adjust the shims a bit to get it back to a normal IP range
 
Thanks tbone. It actually started with the top pressure 165 (it took about a minute for it to reach this) but adjustment of the cap brought it down to where it is now. I have extra shims and can start with that but was hesitant to head off for cave couse as is so wanted SB's opinion.
 
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Thanks tbone. It actually started with the top pressure 165 but adjustment of the cap brought it down to where it is now. I have extra shims and can start with that but was hesitant to head off for cave couse as is so wanted SB's opinion.

you have the mk25 manual yeah? I'd just take it apart and readjust the shims to get it back to 135 with the cap in whatever position it should start in, and then go from there. Report back, it shouldn't explode ;-)
 
you have the mk25 manual yeah? I'd just take it apart and readjust the shims to get it back to 135 with the cap in whatever position it should start in, and then go from there. Report back, it shouldn't explode ;-)
I actually have a rare day free tomorrow. Will let you know how it goes. :wink:
 
I thought the 25 had an adjustment screw vs. shims like the 20....
 
I thought the 25 had an adjustment screw vs. shims like the 20....

the scubapro guys can confirm, but it should be shims for rough tuning, and screw for fine tuning. With high IP, it's possible there are some extra shims in there for whatever reason, or that the screw isn't far enough out

It is also possible that the piston got damaged somehow and needs to be replaced
 
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Ok. Took it apart. First the washer that is suppose to be under the seat retainer was missing. Inside was the internal "washer" plus one shim. Placed the washer under the seat retainer and left the shim in place and reassembled and now this...

 
well it's amazing what happens when things are put together correctly! That's now still showing some IP drift, and it could be that the seat was damaged from improper assembly.

Leave it on there for an hour or so and see where it goes. If it stays put, then I would quick tap the second stage a bunch of times to see if it stabilizes, adjust the IP to where it needs to be, and then let it sit for another hour or so. If it still stays put, I wouldn't have a problem with it. It isn't ideal, but it will work
 

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