Tue Jan 18, 2011 8:35 am
I checked mine last night and have a little more info. The outer screw is a locking screw/protective cover. It's not needed for the OP valve to function. I now remember why I did not fully dissamble the op valve, the internal adjustment screw on mine is staked in and will not move- not worth damaging it for a photo since it works. The threads appear to be 24 pitch but the bore is slightly larger than a standard 3/8-24 so I suspect it's metric. The good news is a 3/8-24 will screw in but the bad news is the hole is too shallow for most plugs to go into and the face of the hole is not bored to accept an oring. SOOO, you either have to fix the one you have, disable it (rubber gasket in place of the current gasket????) or have the hole bored to accept an oring. If you intend to use the second stage, the disabling option is a bad idea, exploding hoses are not fun. How to fix what you have?? Since the internals of the op valve are just a spring and a plunger, they are almost certainly OK, sticking maybe but a good cleaning would fix that. The most likely problem is the rubber seal which you should be able to reproduce. That leaves the cover. An original is going to be hard to find without buying an entire reg. Making one would not be too difficult but finding a suitable chrome plated brass plug the right size might be difficult. My suggestion is to replace the gasket and see what happens, it you get it to seal, dive it. Lets face it, it's not likely anyone would want to dive this reg in serious conditions, it's a play in the pool or quarry reg.
Herman