Can't get Scubapro MK15 cap off

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Hi,

A reputable dive shop told me they could not get the end cap off my MK15 1st stage regulator. Their suggestion was to buy a new regulator. They told me it was probably corruted shut.

I find this difficult to believe because I had it serviced by them a year earlier and only have about 30 dives since then.

Anyone have any suggestions on how to remove this cap?

I have tried soaking it in water for 48 hours. This did not work.

I was thinking about heating some water to about 120 degrees leaving it in for 20 minutes then putting it in a bag of ice water. A few cycle of this may free up the mating surfaces. I don't think it would hurt anything in the reg?

Also someone suggested some vinegar or lemon juice?

Thanks for any suggestions.

-John
 
Safest bet should be to send it to a Scubapro service center with an explaination of the problem and the service from the LDS. If that LDS is an authorized dealer and you provide receopt for the last service and your original purchase receipt, it may be covered under warranty.

I'm not very familiar with the Mk15, but looking at the schematic, looks like the HP seat retainer (I assume that is what you are talking about) is protected from corrosion by an o-ring. So problem may be overtorqued thread damage rather than corrrosion. But with the seal protected by an o-ring, it shouldn't have been overtorqued unless some monkey was experimenting at another way of lowering the IP without having to open it up again. The hot - cold treatment is a good approach to breaking a little corrosion. Acid bath might be a bit rough on finish if used for more than 10 minutes (not really enough time to soak in) and even rougher on soft parts.

I might also have a hard critical look at that LDS.
 
awap:
Safest bet should be to send it to a Scubapro service center with an explaination of the problem and the service from the LDS. If that LDS is an authorized dealer and you provide receopt for the last service and your original purchase receipt, it may be covered under warranty.

I'm not very familiar with the Mk15, but looking at the schematic, looks like the HP seat retainer (I assume that is what you are talking about) is protected from corrosion by an o-ring. So problem may be overtorqued thread damage rather than corrrosion. But with the seal protected by an o-ring, it shouldn't have been overtorqued unless some monkey was experimenting at another way of lowering the IP without having to open it up again. The hot - cold treatment is a good approach to breaking a little corrosion. Acid bath might be a bit rough on finish if used for more than 10 minutes (not really enough time to soak in) and even rougher on soft parts.

I might also have a hard critical look at that LDS.
As said above, I work at a scubapro service center and if the reg has been serviced last year and by a authorised center it will be covered by warranty don't try to fix it yourself that will screw up any warenty claim
 
scubadoguk:
As said above, I work at a scubapro service center and if the reg has been serviced last year and by a authorised center it will be covered by warranty don't try to fix it yourself that will screw up any warenty claim


I am not the original owner and don't have a receipt.

So I need to find a way to get it off myself.

Yes it must be the HP seat retainer. It has 2 small holes to unscrew the cap.

Thanks
 
The proper tool has two pins that engage the cap...... what's been tried thus far?
 
Genesis:
The proper tool has two pins that engage the cap...... what's been tried thus far?

The LDS used that tool your described which did not have enough leverage?

He then put two allen wrenches in a vice and tried to turn the body of the 1st stage. I think he broke one of the allen wrenches and gave up.

The holes have been enlarged a little from this effort.

I tryed the same after soaking in water for 48 hours. No Luck.

Thanks
 
Hmmm..... That part is made out of brass (as is the entire reg - its chrome-plated brass) and if the pins don't provide enough leverage than either someone grossly overtightened it (in which case the threads on the plug, body or both are damaged - and you're probably hosed) or its BADLY corroded together.

The latter is fixable with heat and PB Blaster, but beware - heat and things that need to hold pressure don't get along well, and PB Blaster isn't something you want to breathe. You WILL need to be real thorough with the cleaning if you get it apart, and the plug will likely need replaced along with all the soft parts. Its entirely possible that the heat could make the reg body unsafe to hold the pressure required too, and there's probably no GOOD way to know if that has happened or not after the fact, other than being real careful about HOW hot you get it.

If its "get it apart or its junk" at this point, then I'd up end the reg so the plug points up, soak it in PB overnight, then try with the proper wrench while using heat on the body. Be aware that you do not want to get it very hot, lest you damage the metal's strength. This will require some forethought, particularly if the holes on the cap have been damaged, since if they're not straight you won't be able to develop much torque on the plug.

I've yet to be unable to get something like this apart (even things that are badly seized up with salt water corrosion) using this kind of technique, but when I need to do something like this its typically some assembly on my boat - no high pressure gas in there in normal operation :D

This just plain old fashioned shouldn't happen with these regs - the threaded part of the plug is behind an O-ring, so there should be no way for ambient water to get in there and corrode things. This tends to point towards some tech in the past getting "cute" in some way, or salt water getting INSIDE the airpath (real bad - if that's happened there's probably plenty of corrosion all through the inside, in which case the body may be toast.)
 
If the special tool can't put enough torque on it to turn it, something is seriously wrong. And I don't believe it is corrosion if that reg was still working. You might get this "reputable LDS" to talk to you about what is wrong and how it could happen. If this is the same shop that last worked on it, I'd be looking for him to make it right. Perhaps you should ask him to send it back to a service center if he can't handle the job.

But I think you might be better off talking to the nearest service center yourself. I'm afraid I smell a rat.

I made my own special tool to service my Mk5/10. Before that I use a pair of craftsman mini pliers with rounded needles. Neither my tool nor the pliers were capable of generating much torque, and they never had to. Thisn is one of those snug seals that works by engaging one or two o-rings.

I'm surprised DA Aquamaster hasn't chimed in yet. You might want to PM him (or wait, he'll show up eventually) and see what he advises
 
Yeah, a regular pin spanner wrench should be able to get this plug out. Its not held in place normally by torque - the seal is made by an O-ring, and under pressure its not going anywhere.

I'm with awap on this in terms of where to go, assuming you have some kind of service record on this to fall back on. If you don't, then you have nothing to lose. I could easily get it apart, but I might destroy it in the process, which is what I'm afraid is going to happen if you get aggressive with it.
 
If we are talking about the seat retainer, it is o-ring sealed and corrosion would not be the issue. And I have never actually seen one of these get stuck. They are also very hard to overtorque with the SP multitool.

But if we are talking about the "cap" that is something entirely different. The cap is the part of the reg with the holes in it for the ambient chamber and is located between the main body and the swivel. These get stuck fairly often if they are not properly rinsed as the threads on the cap and body can accumuate deposits and get nicely stuck together.

The MK 15 was designed to use a spec boot and a silicone filled ambient chamber so the holes in the ambient chamber are rather small making thorough rinsing difficult. Many shops don't refill the spec chambers with silicone since the advent of the TIS kits and SP is not promoting environmental silicone anymore so often no silicone ends up in this area. At a minimum I think it is a good idea to lubricate the threads with silicone when reassembling the reg as it goes a long way toward preventing the problem I suspect you might currently have.

You need the proper tools and a vice but stuck caps can almost always be freed with the proper spanner and a rubber mallet with the reg clamped in a padded vice. Some soft to medium taps on the spanner with a 16 oz rubber mallet will accomplish a lot more than trying to torque on the spanner alone. The impact and vibration do most of the work in freeing the frozen parts.

If the seat retainer is in fact stuck, I would use the same approach to free it with some soft blows on the tool with a rubber mallet while the reg is in a padded vice.

I would NOT use heat on a Mk 15. In addition to the normal concerns about softening the brass of the main body itself, the upper bushing in the Mk 15 is plastic and pressed into the body in such a way that it is not removeable or replaceable. If you melt it or deform it, your main body is hosed and you will need to buy another one. Brass is a great conductor of heat so the potential of melting the upper bushing is pretty high.

The Mk 15 is also a pain to service and the snap ring that holds the lower bushing and HP O-ring in place is a pain to remove unless you have snap ring pliers with really long and skinny jaws. The possibility exists that the tech is just not overly interested in servicing the reg the in the first place.
 
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