When we bought our MK ll in 2001, within the first year the boat would slow sometimes. I could see the shaft slow while watching it with the engine running at constant RPM. Dealer insisted it was shift connection on the transmission and adjusted it several times. Problem not solved. Transmission was removed from the boat twice and checked in a shop, who could find no problems with it. Seemed to work on the workbench. Put it back in the boat, still the same problem. Long and short of it, Catalina replaced the transmission. No more problems 14 years later.
Maybe a similar problem with your transmission?
Jack
C34 MK ll 2001, FK/TR M35BC
Maybe a similar problem with your transmission?
Jack
C34 MK ll 2001, FK/TR M35BC