Scuba Pro MK25 help

[rha600]

Good evening.

I've got a small problem with my MK25, and I'm planning on taking it to the dive shop tomorrow but I wanted to get some opinions on it here as well.

It started back in May, after I had it serviced I went diving and when I came up from the first dive I could hear some hissing. My dive buddy said he noticed a very small leak coming from the 1st stage, nothing to worry about, but it was there.

So after switching over to my other tank, I opened the valve and boom, I heard the hissing, only this time it was worse. After some inspecting I could see the swivel portion on the bottom where the LP hoses connect was loose and the o-ring inside was bulging out. So I stop at the dive shop on the way home, and the screw/bolt on the inside that holds that on had come loose. He said he's only seen it happen twice before, but he tightened it up right there and then (even stopped eating his dinner to do so) and off I went.

Everything has been fine, and it's working however on my last dive, my buddy again said I had a small leak, and he even had a photo of it. It's a small but stead stream of bubbles coming from the first stage, and I believe it's enough to use up approx 300PSI after a 50 minute dive in 20ish feet of water. I only say that because he and I are usually dead even with air, but the last couple of dives I seem to have used about 300-400 more PSI then he did. I'm assuming based on super scientific research that this might be why.

So anyway, not that I'm done rambling, the real questions I had are, has anyone had this problem before, and also can someone tell me if the swivel piece on their MK25 seems loose at all. Of course it will spin, but will it rock back and forth at all? I can't remember how tight it was right after it was fixed but right now it does rock back and forth just the tiniest bit. Not nearly enough for the o-ring to come out, but if it's on it's way to that I want to make sure it's fixed for good this time.

 

[redacted]

Good evening.

I've got a small problem with my MK25, and I'm planning on taking it to the dive shop tomorrow but I wanted to get some opinions on it here as well.

It started back in May, after I had it serviced I went diving and when I came up from the first dive I could hear some hissing. My dive buddy said he noticed a very small leak coming from the 1st stage, nothing to worry about, but it was there.

So after switching over to my other tank, I opened the valve and boom, I heard the hissing, only this time it was worse. After some inspecting I could see the swivel portion on the bottom where the LP hoses connect was loose and the o-ring inside was bulging out. So I stop at the dive shop on the way home, and the screw/bolt on the inside that holds that on had come loose. He said he's only seen it happen twice before, but he tightened it up right there and then (even stopped eating his dinner to do so) and off I went.

Everything has been fine, and it's working however on my last dive, my buddy again said I had a small leak, and he even had a photo of it. It's a small but stead stream of bubbles coming from the first stage, and I believe it's enough to use up approx 300PSI after a 50 minute dive in 20ish feet of water. I only say that because he and I are usually dead even with air, but the last couple of dives I seem to have used about 300-400 more PSI then he did. I'm assuming based on super scientific research that this might be why.

So anyway, not that I'm done rambling, the real questions I had are, has anyone had this problem before, and also can someone tell me if the swivel piece on their MK25 seems loose at all. Of course it will spin, but will it rock back and forth at all? I can't remember how tight it was right after it was fixed but right now it does rock back and forth just the tiniest bit. Not nearly enough for the o-ring to come out, but if it's on it's way to that I want to make sure it's fixed for good this time.

Did your shop use a torque wrench when he tightened the swivel retainer? A little rocking is normal. If a properly torqued retainer is coming loose, it would probably be best to simply replace the retainer and the swivel. (As a DIYer, I'd probably come up with a less expensive solution,) If there was no torque wrench involved, than that is another problem with its own solution.

 

[DA Aquamaster]

There is a small, skinny plastic washer about a 1/2 inch in diameter between the retainer and the swivel. Make sure that it is in fact there as if it isn't you'll get an excessive amount of rocking.

If the o-ring was extruding between the swivel and swivel cap it should have been replaced as almost inevitably the o-ring is damaged when that happens. Re-tightening it by itself is not adequate, the o-ring needs to be replaced as well.

 

[rha600]

I am 100% positive there was no torque wrench used as I was standing there watching him when he fixed it. It was just a T handle type of Allen driver.

Right now as I said, there is only a little rocking, so the other thing I was wondering is maybe the o-ring was damaged when it blew out the first time and that is why there is the slight leak. I'm planning on bringing the photo to the shop with me so they can see what it looks like and how bad it is, or isn't and I was going to see if they could replace the o-ring. It might just be as simple as that.

Thank you for the info and the quick response.

---------- Post Merged at 08:28 PM ---------- Previous Post was at 08:23 PM ----------

There is a small, skinny plastic washer about a 1/2 inch in diameter between the retainer and the swivel. Make sure that it is in fact there as if it isn't you'll get an excessive amount of rocking.

If the o-ring was extruding between the swivel and swivel cap it should have been replaced as almost inevitably the o-ring is damaged when that happens. Re-tightening it by itself is not adequate, the o-ring needs to be replaced as well.

Thank you. The o-ring part is what I was thinking as well. I'm going to ask about that tomorrow.

 

[redacted]

While the o-ring is a possibility, the fact that a connection with a torque spec from Scubapro loosened and no torque wrench was used makes the professionalism of the shop very doubtful.

 

[Couv]

Yep, to sum it up you want:
1) The cap removed.
2) The swivel o-ring replaced and lubed.
3) The swivel retainer washer verified to be installed.
4) The swivel retainer correctly torqued.

May as well have them replace and lube the piston head o-ring too while the're in there.....oh what the hell, you should join us in the DIY section and learn to service your gear.

 

[rha600]

Now that I know there is a DIY section, I think I will join you. haha.

---------- Post Merged at 07:36 AM ---------- Previous Post was at 06:30 AM ----------

Cool. I have ordered "THE" two books on regulator repair and maintenance. I'm going to read through those and then eventually pick up the proper tools.


btw, here is the photo of the leak. Please ignore the bald spot. haha

 

[Couv]

Good deal. While you are waiting on the books to arrive, go here http://www.frogkick.dk/manuals/ and download the manuals for your regulators.

Good luck and keep us posted......welcome to the Dark Side.

Re the bald batch:
Men who have receding hairlines are thinkers.
Men who have a bald patch on top of their head are lovers.
Men, (like me) who have both-think they're lovers.

 

[rha600]

HAHAHA I never saw that bald patch saying before.


As for the manuals, already done. I downloaded them actually before I ordered the books.

Right now I'm THINKING about ordering the scubapro tool kit. Seems to have just about everything I'd need except the install and universal tools. But again, I'm going to wait until after I go through the books before ordering any tools.

 

[halocline]

Just to make sure we're talking about the same thing, your reg is leaking from the joint between the two halfs of the body where the swivel is, not from the spot where the yoke connects to the body, correct? It's much more common for the yoke spot to leak because that's HP air.

The swivel retainer is a fairly crucial torque spec, but not because it comes loose, because over-torqueing it can damage the somewhat delicate swivel retaining bolt. This was a real problem on the older MK5s which used a chrome plated brass bolt, then SP switched to SS and increased the allowable torque. It's still very low, something like 70 in/lbs. That's less than 6 ft/lbs.

If that swivel bolt did in fact come loose, I'd suspect something was wrong with either the threads in the swivel itself or the bolt, or maybe with the plastic washer. Either way, once it came loose and the guy didn't replace the extruded o-ring, chances are you don't want him working on your gear.