Mares MR22 worth rebuilding?

[Ecru]

I've bought my first regulator set - an old Mares MR22. It has a black coating over brass (I think) and titanium written on the Abyss 2nd stage. I'm guessing it is from 96-99 going by this thread.

On hooking it up to air the intermediate pressure briefly hovered around 150psi, then rose to 200psi with the 2nd stages leaking.

Pulling them apart, and they are somewhat sad.

Points of note:

• it is possible incorrect parts are present
• 185034 Plate, spring base cracked and is damaging 182022 Diaphragm
• marks on 185002 Poppet appear uneven and 186128 Poppet seat shows some damage under a magnifying glass, probably too much since it was leaking?
• lot of corrosion on the body of the 2nd stage MR12 III body

Is there a recommended old Mares parts / kit supplier? Are the spring base plate and poppet seat only available second hand?

Is it worth rebuilding them?

I like the idea of a metal second stage since in theory it helps with a dry throat. Otherwise a new Dual 15X is an option, if it is as good as a MR12 or MR22.

Thanks for your opinions.

More photos to come.

 

[Ecru]

Further photos.

 

[Mobulai]

Indeed the set you have is the Titanium one, it’s not actually all Ti, but Ti plated brass

The MR22 is very well known for its stable IP (~132psi), it’s for sure worth it (esp. knowing that the MR15 and 12 are essentially the same 1st stage but with different bodies)
The heavy weight of the 1st could be a factor for you

Regarding the IP creep/leak; I’d check the orifice (volcano) under a microscope/loupe/magnifying glass for knicks, and try to dress it with a micromesh if there’s any — ana alternative is buying a new HP orifice (if you have the connection )
You need a HO seat (poppet) anyways (the square thing with a blue circle — mares terminology is wildly different from SP one I’m used to)

The spring base, I’m not sure if that comes with the service kit or not — I’d ask someone more familiar (@lowwall @rsingler )
For SP this is part of the kit

I’d say worth it to rebuild, but it would depend on costs/preferences

I’m always for reviving old regs

 

[Searcaigh]

I currently use two MR22s in my stable of regulators, both are from the late 90s.

Great regulators and as far as I know all parts still available.

 

[Mobulai]

The spring base, I’m not sure if that comes with the service kit or not — I’d ask someone more familiar

I do know for a fact that the parts you need (HPseat ie poppet, volcano ie orifice, spring base, diaphragm) are available for individual sale to the public at GIDive store (not the US facing portal tho)
I bought from them diaphragms and poppets already for my singular MR22T (same exact reg, I haven’t opened it yet)

Ok the spring base seems out of stock

 

[Ecru]

Thanks for that info @Mobulai.

I've also seen poppet parts on jonasdive and ebay. However the spring base remains elusive so far.

The different naming for Scubapro is entertaining.

 

[Mobulai]

The different naming for Scubapro is entertaining.

It’s wild

An idea comes to mind (if that base isn’t part service kits) — you can always seal the reg with the TPB kit (the env seal) which I suspect (from memory)either eliminates it entirely or has a replacement one

I’d still wait on the experts here on the boards to weigh in

 

[Mobulai]

An idea comes to mind (if that base isn’t part service kits) — you can always seal the reg with the TPB kit (the env seal) which I suspect (from memory)either eliminates it entirely

Indeed it does eliminate the diaphragm entirely

Can we now introduce Mares' current environmental seal system? They call it Twin Balanced Piston. That's more marketing fluff than useful description, but it does have some theoretical advantages over the standard design. Perhaps the largest is that all the parts are metal except for the conventional flexible diaphragm that forms the environmental seal. This should allow for a more precise and consistent transfer of force to the pin pad.

Here's a crop of the schematic:

View attachment 877092

The main diaphragm is replaced with machined metal disc and hollow column (9) that is sealed by an o-ring (10). The outside of the column guides the spring (12) which is preloaded by the regulating nut (22) which is how you adjust IP. The inside of the column accepts the post of the part that replaces the transducer which Mares calls the upper piston (21).

You can see all the parts and how they are assembled in this video (starting at 41 seconds)

 

[lowwall]

Unfortunately Mares doesn't make a TBP kit for the MR22.

I'm just going to list some notes in no particular order.

The part number for the spring base plate changed from 185034 to 46185034 in the mid-2000s. Mares still makes them, but I don't see anyone offering it for sale. You might need to find a friendly shop to help you out. You could also scavenge an unbroken one from a "parts only" 12, 16, 22, 32. It's a non-precision chunk of plastic, so as long as it isn't broken like yours it should be fine.

You need to clean those parts. Here's a good thread. Despite the title, you don't need an ultrasonic cleaner. Recommended ultrasonic solution, time, and temperature?

I've had good luck ordering parts from https://www.maremossoforzasette.it/en/diving/spare-part-scuba-diving/mares-regulators.html . I also bought my MR22 from them.

You've obviously got a bad seal in the first stage. You need a new poppet (the T-shaped piece). You may or may not need a new HP seat (the part with the volcano orifice), but it's only €8.90 from the page linked above. A parts kit from the same source that includes the poppet is €27.50. Given the prices, I'd also be tempted to replace the diaphragm (€3.90), spring (€1.50) and the pin (€2.00, match the length on the one you have).

I personally wouldn't spend too much time on the MR12 III second stage. If the corrosion isn't terminal, you would be OK using it for an octo. But there is a reason Mares went to a larger exhaust valve for all of the second stages after this one. To replace it, you should be able to find an inexpensive Abyss/Voltrex/Orbiter second stage. The other metal option is a metal Proton, which is nice for an octo because it's physically smaller. Finally, the plastic Rover/Prestige (same reg) is also cheap and plentiful and will outperform the MR III if tuned correctly. Avoid the plastic Proton unless it has had the faceplate replaced with one from the metal Proton. The original soft plastic Proton faceplates all eventually disintegrate,

A Dual 15X is a perfectly acceptable regset. But gets you zero style points

 

[Ecru]

Thanks for the mine of information @lowwall, much appreciated.

Are there any special tools you would recommend? There are a few sites around such as this one, but not sure what I really need if any. I already have an IP guage and a sink full of water for cracking pressure.

I was eyeing off some MR12III sets, but will be patient and look for abyss series now.
One look in the mirror cures me of chasing style points.