Mk5 Questions

[halocline]

The MK5 kit comes with 4 o-rings; 010, 022, 013, and (I think)012. There are only two others; both 015. So if you buy a kit and some 015s, you're all set. I had thought originally that the kit only had the piston o-rings but I was wrong.

Then again, the kit has three seats so if you buy some extra o-rings you can get a couple rebuilds out of one kit.

 

[Zung]

... Now I have a cold water-ready O2 clean reg to dive with in the caribbean on air. You guys are a bad influence.

I'm also prep'ing our gears for our next trip to the Maldives. I wonder if I should do the same: yank all the good original EP rings and put aftermarket Viton's and fill the ambience chambers. This time of year, it's the North-East monsoon over there, and the water temp is an icy 80°F. Maybe I should also dust off the dry suits and O2 clean them.

...Other brands often include all the o-rings, since they are so cheap...

The current kits for the MK20/25 also include ALL o-rings, while the MK10Plus kits come with ONE o-ring for the same price. I guess it depends on their mood.

 

[halocline]

I read in another thread about the current MK25 kit including "all" the o-rings, so I decided to look at a MK20/25 schematic. Other than port plugs, there are only 6 o-rings: HP piston, 2 LP piston, HP seat, turret, yoke retainer. The seat and piston o-rings always came in the kit, so if this is true, there are only two extra o-rings; an 017 for the turret, and an extra 011 for the yoke retainer. Big deal....

That is, unless SP got extra generous and included port plug o-rings.

This also dispels the myth that the MK20/25 is so much more complex than the MK5 IMO. The o-ring count appears to be exactly the same; the MK20/25 does have the bushings, and there is an o-ring in the piston that apparently can leak occasionally.

 

[Zung]

... That is, unless SP got extra generous and included port plug o-rings...

Yes, they do: 4 x -010EP70 LP & 2 x -011EP85 HP plugs, plus that funny -013EP85 to help with some possible leak at the seat retainer/adjustment of the MK25.

... This also dispels the myth that the MK20/25 is so much more complex than the MK5 IMO.

The bushing system plus the 2 variants MK20/MK25 do appear more intimidating on paper or screen, but I find the servicing of the MK20/25 is much quicker than the MK5/10 because the HP o-ring falls right out and drop back in.

 

[LeadTurn_SD]

The current kits for the MK20/25 also include ALL o-rings, while the MK10Plus kits come with ONE o-ring for the same price. I guess it depends on their mood.

Lest you think I was complaining about the Scubapro annual kit, the Mares kits for their diaphragm regs came with every o-ring under the sun.... but no diaphragm .... I think their reasoning may be that since all the Mares regs use the same diaphragm, the LDS will just have a bin full of them, and the tech just needs the model-specific rebuild parts to be in the annual kit, and he/she can grab the rest as needed.

Anyway, my Mk5 has found a happy home (for now) as a stage / pony regulator.

I'll post Mk5 "Baby Pictures" soon, since you are all "God Fathers"

Best wishes.

 

[Zung]

According to the official Mares manual, the diaphragm is an "inspect" item that get replaced only if it's damaged.

Interestingly, they suggest a replacement of the poppet every other service.

 

[LeadTurn_SD]

According to the official Mares manual, the diaphragm is an "inspect" item that get replaced only if it's damaged.

Interestingly, they suggest a replacement of the poppet every other service.

Sorry for the fftopic: (I should just start a new DIY thread ), but some brands (many?) consider the diaphragm an "annual" item....

Zeagle states that the diaphragm MUST be replaced any time it is removed, and they say that this applies to all diaphragm regs, not just Zeagles!

I have both Zeagle (two Flathead VI's) and Mares diaphragm 1sts (too many Mr-22 Abyss and Mr-12's to count ), and cannot say that the diaphragm in either brand is more or less durable.

Since I only service "as needed" (not every year), I just routinely change the diaphragm...

Best wishes.