Just wanted to let you know that I installed pump and system works fine. Thanks to all for your assistance.

Hey - just wanted to say 'thanks' to OSO. Was having trouble with my Captains Call / Silent Choice pneumatic system. Diverters would close to 'thru hull' position but would slowly open while running. Read this thread ... took the check valve apart ... had dust in it ... cleaned it up, reassembled, works great. Who knows what the shop would have charged, not to mention the check valve is $100.