What could cause this problem with SP MK25?

[Hank49]

well, hold on one second. I have (2) MK25 for my doubles. I have never switched the regs around to see if the first or second stage was the problem. So in short, I have not isolated to the second stage. I really have no clue as to which is problematic

Oops, sorry. In my experience, if the spring on your piston isn't broken, it should be opening and allowing air in from the tank. I don't understand how it could function and air would not go into the IP housing for all your LP hoses. If your HP seat isn't working, you'll get free flowing from the second stage with the lowest pressure adjustment. (if you have more than one 2nd) I would bet it's the s600. Or, I guess it could be a piece of dirt bouncing around inside the IP housing and occasionally gets over the port going out to your s600. ?? But again, I'd take it to someone who really knows what's going on. Down stream regs shouldnt jam up like that. DA Aquamaster is the real reg expert here though. maybe PM him.

 

[redacted]

I really think that dirt or damage in the S600 is the prime suspect. But, for me, an IP check is just a routine part of troubleshooting before you start fixing.

 

[HNITSUJ]

I am not fixing anything. Its in for its yearly service and the issue was noted.