:) Scubapro MK11 with balanced S600 or S500 or G250

[DA Aquamaster]

How'd the c300 shake out? Seems like it never gained a lot of popularity.

I had some problems with it in silty, sandy side mouth passages. It used a pair of narrow grooves in the plastic air barrel that were engaged by ribs on the poppet. If you got a piece of sand in there it could impede the movement of the poppet.

Scubapro pretty much blew me off when I mentioned it at a reg repair clinic. They're not real fond of people saying their new products have issues. If they'd send them out to people who dive them in demanding conditions for testing in the first place, rather than doing it with sales reps doing pretty fish dives in tropical resorts, they'd find this stuff out before it goes into full scale production.

The good news is that the C350 uses an oblong shaped poppet with a matching oblong internal profile in the air barrel to keep the poppet aligned while eliminating the potential source of binding due to sand.

It wasn't a major deal with the C300, to the point that I have not explored the option of getting a 350 air barrel and poppet for the two C300s I have, but it was (and remains) a potential issue on the C200 and C300.

 

[DA Aquamaster]

Update for anyone who's interested. I pulled one of my MK17s apart to compare. Bottom line, unless you're doing a full MK11 to MK17 conversion including dry chamber, the only parts that can be swapped are the diaphragm and it's two washers (MK17). All other parts are completely different sizes and are not interchangeable. I'll swap to a MK17 diaphragm and it's two washers just for s%#€# and giggles. From what's been said by the experts I'm very unlikely to notice any difference. I'll do an ip check/recovery before installing the MK17 parts just to see if it behaves any differently. If I see or notice anything I'll report back.



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The change in the Mk 17 adjustment screw and spring is a recent change. The older Mk 17s used the same spring and the same adjustment screw. I have a couple converted Mk 17s that still have the Mk 11 screen printed screw in them.

 

[buddhasummer]

Thanks for the info. That being the case then I guess it's only the diaphragm and two washers that account for differences in flow rate. Good to know.

Added:

Changed post to specify MK17 Evo in light of DAs post above.

 

[buddhasummer]

Was "chatting" to axxel and he brought up an interesting point, wondering how well the thinner MK17 diaphragm, which is of course sealed off from the elements, would hold up over time being exposed in the MK11. No way to know except to try it I guess.