Genesis

The Snap-tite solenoids can be disassembled with reasonable ease (assuming someone hasn't epoxied them as a "corrosion inhibitor"!) You need to deal with a spanner for the actual valve body retaining nut, but its not hard to get apart.

The seal itself is a puck and not really replacable (kinda like the puck in a second stage reg) but the internal mechanism is just a magnetic stick and a return spring, along with the channel they ride in. Its primarily brass and stainless, but is not going to fare well if moisture - especially SALT - gets in there (dissimilar metals corrosion and all.) In addition the seal is a knife-edge type orifice and once that gets eroded it will never seal properly again.

If class work requires disconnection underwater IMHO this is a serious flaw in the course - unless they instructor is including a new solenoid in the price! There is no way that you can get salt water into these (at least the SnapTites) and not have them screw up on you in reasonably short order for this reason. I'd consider an underwater disconnect, especially in salt water, to be cause to immediately replace the solenoid given what I've seen from taking these apart.

I don't know what the "new" model that is being used in the Meg (or other models of solenoid) are like inside..... but I bet they're not very different! In particular the dissimilar metals issue is one that's going to be hard to get around, given the realities of what has to be in there for the valve to work!

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