Scubapro MK15 serivce

[Jacobyz]

I usually submerge everything (including rubber and plastic pasts) of my reg in a solution made using WC-cleaning detergent, which contains a lot of acid. Apparently it does no harm to rubber and plastics...

Thank you!!

 

[Jacobyz]

And, thank you, as well. I do not want to jinx myself, but with the “specialty” long-nose pliers I was able to easily remove the cir-clip and access/remove the HP-side bushings and piston shaft o-ring more readily than on my MK5’s and MK10’s (although with Herman’s tools, I was able to successfully accomplish both installation and re-assembly of same). Fingers crossed as to re-assembly of the MK15. My departed uncle, who taught diesel mechanics at the university level, always drilled into me the importance of acquiring and using “the correct tool for the job; no shortcuts.” Shout-out to all of the contributors on SB, Herman, Bryan at VDH for seats and parts, plus @rsingler for the MK15 schematics.

 

[halocline]

There's a MK15 assembly tool which ensures that the seat and bushings are correctly installed. If you don't have that, try to find some sort of plastic or wood dowel that you can use to seat the o-ring and bushings one at a time; just push them in place with a healthy bit of PTFE grease or silicone. Then get your circlip installed, and that will hold everything in place while you insert the piston (you NEED a piston bullet tool for this) from the ambient side. It's fairly straightforward.

One of my MK15s is going on 5 years since I rebuilt it last and it still locks up perfectly with zero creep.

 

[Jacobyz]

There's a MK15 assembly tool which ensures that the seat and bushings are correctly installed. If you don't have that, try to find some sort of plastic or wood dowel that you can use to seat the o-ring and bushings one at a time; just push them in place with a healthy bit of PTFE grease or silicone. Then get your circlip installed, and that will hold everything in place while you insert the piston (you NEED a piston bullet tool for this) from the ambient side. It's fairly straightforward.

One of my MK15s is going on 5 years since I rebuilt it last and it still locks up perfectly with zero creep.

Thank you. Yes, I have the assembly tool and a piston bullet which came with my MK5/10 piston o-ring tool set. Best

 

[Open Ocean Diver]

There's a MK15 assembly tool which ensures that the seat and bushings are correctly installed. If you don't have that, try to find some sort of plastic or wood dowel that you can use to seat the o-ring and bushings one at a time; just push them in place with a healthy bit of PTFE grease or silicone. Then get your circlip installed, and that will hold everything in place while you insert the piston (you NEED a piston bullet tool for this) from the ambient side. It's fairly straightforward.

One of my MK15s is going on 5 years since I rebuilt it last and it still locks up perfectly with zero creep.

Nice what does it lock up to on low tank pressure, like 500 or so?

 

[JamesBon92007]

Yesterday I tried out my MK15 and G200B in the pool again and it seems to work fine as long as I don't think about all the little details and just breathe from it If I adjust the second stage so it's easy-breathing then it still tends to free-flow very slightly when I'm looking downward but ScubaPro seems to think that's OK so what the hell do I know? Personally I prefer to crank it down to where it no longer does that because I feel like I'm wasting air. I have not reported back on the lever-height adjustment procedure because I'm not yet sure how well it worked. If this was one of my other regs I'd think it needed a new LP seat but it has a new poppet and LP seat and O-rings and everything else seems OK. Someone suggested that the balance chamber might be loose or the spring is too weak so I'll be looking at those possibilities.

 

[rnln]

Finally, I can call it done. I want to say thank to everyone, especially Couv, who is patience with me on every problem I encountered with.

There is one thing I want to point out as reference for any newbie (like me), who have never seen inside the MK15 and is in the same situation as I was. In the area where the plastic bushing on the HP side, if anyone remember I was asking about my plastic bushing was rotten because when I poked it with a tooth pick, I felt that it is deteriorated. So, I decided not to remove it. yes, I cleaned it well. When I install the 010 piston o-ring/shouldered bushing/circlip. I had to push very hard to get the circlip in place. Finally, when the piston is pushed through (with the bullet head tool), the piston knife shaft cut/slid off a nice portion of the 010 o-ring. The cause was that when I jammed/pushed the circlip down, the o-ring got compressed too much and ID became smaller, a lot smaller.

To make long story short, I finally found that my old piston 010 o-ring was already break/slid off in 1/2 before I got to it. One half was melted on top and merge with the plastic bushing for some reasons, think about cheese melted on pizza. Therefore, when I looked at it the first route, I thought the whole thing was the plastic bushing. How did I know that? Well, at one point, I knew something was wrong when my piston couldn't go through easily, but didn't know what it was. I decided to poke on the plastic bushing since the culprit was in that area anyway. Luckily, when I poke around it for a while, the melted portion came off and exposed the nice and clean white plastic bushing. I will include some pictures of before and after the melted o-ring came off so you can see the different. Hope one day this helps someone.

 

[Couv]

@rnln Thank you for the update. Congratulations on getting that PIA back together. What is the final verdict? Is the IP on target and holding steady?

Cheers,

Couv

 

[Rusty Shackleford]

Scuba Pro MK 15 service kit

Ya'll owe me!

 

[Couv]

Ya'll owe me!