I answered this over at The Hull Truth, but will post it here too as there may be others with TrimMaster systems. Here is a link showing how to take one apart and replace the O-rings http://www.offshoreonly.com/forums/sonic/212239-trim-master-trim-tabs-fixed-me-photos.html But TrimMaster has been out of business for quite some time (10 years or more?) so finding replacement O-rings might be hard.
