The problem with sucking salt water is that the larnyx will close and then you will not suck anything. I managed to flood my lungs with salt water by determined sucking of a leaking regulator this past summer. That is what happens when a feller is drowning. The larnyx closes and then there was no more sucking. And being still at 90 feet and with a minor deco obligation and seperated from my gaggle of buddies I was pretty much close to dead. I grayed out but managed to maintain some semblance of consciousness by focusing on completing a task, clipping my camera up and deploying my sausage, whilst (mentally) whistling Dixie waiting for my larynx to open enough to get some air and more importantly expel the seawater now residing in my lungs. It took about two minutes and while I cannot be certain of the time I figure I had not gotten a clean breath in close to five minutes. Yes, I survived, yes, I bled from my mouth and lungs, yes, I got pneumonia, yes, I kept diving for the remainder of my trip. My point is, do not plan on breathing much in the way of seawater, lungs are not gills and we are not designed for it. Best to be avoided.
So, I have began an upgrade and reevaluation program (not just equipment) that is mostly centered around Mark V and Mark 20/25 and a new Mark 17 firsts coupled with a small fleet of G250, G260 and a couple of R190s as primary sets and an AL Core set and Titan LX set for my working regs. And anything that does not have an S on it (save for my Core/Titan LX/Legend) somewhere is being demoted and relegated to pretty fish dives.
I got a Mark X from one of the "usual suspects" and it is not set up for a Spec boot and it has the teeny tiny little ambient holes. I think I will just squirt it full of silicone and slip a road bike tube over or if feeling brave, put it in my drill press and size the ambient holes up with a number 21 drill bit. I think the woes described to and of piston regs and sand are perhaps a little exagggerated. Though Scubapro could have made rinsing the piston/spring chamber easier by providing the large ambient holes of the Mark V in the later second stages, well, I guess they are back to that now.
I have seen a diaphragm regulator lock up from being flooded. It was a Conshelf. The amount of water is very small. The regulator did clear itself but not immediately. In Bonaire a few months back my wife's Legend was fitted to the typical horrid resort K valve and it began to leak profusely from the valve face O-ring. One of out group managed to reseat the first stage by shutting the valve off and loosening the regulator. The Legend has ACD. The ACD valve must have closed as no water was found in the first stage. The internal condition was found to be pristine when I later opened it up. It was such an attempt to fix a leaking valve some approximately 50 years ago in Little River that resulted in the Conshelf first flooding and then locking up. The regulator had hit the ceiling and bent the yoke knob and was spewing precious air at a most inopportune time. At least that is how I remember it, a lot of brain cells have died in the interim.
James
) but it isn't fair to make such sweeping judgements based on the exceptional exceptions. It is definitely not a reason to chose diaphragm first stages over piston especially when in reality one can find more justifications, including serious ones, to use piston first stage instead of diaphragm one.
