Bauer Mariner 2nd stage climbs 2 high - Trips safety valve on separator

[SCUBAfy]

Hi all, thanks for help in the past. New problem with old beast. Started with pressure rising too high (over 12-1500psi) after a while, and the safety valve on top of the water separator canister to ACD, would rhythmically start to trip. Now does it about 20 seconds after starting and continues after shutting down until pressure drops off. Pressure rises in 3rd only up to the 12-1500. Just replaced 1st-2nd- and 3rd stages valves today. Still does it, no change. HELP!! Any ideas?

 

[windyairman]

Hi
Suspect 3rd piston /sleeve frozen

 

[SCUBAfy]

Hi
Suspect 3rd piston /sleeve frozen

Thanks for the help. Gonna pull the head off tomm. Any helpful hints on replacing? Saw only one thread referring to it. Seems pretty straightforward assuming the sleeve comes out easy.

C