propshaft

Hey everyone, I apologize for the basic questions, but I truly appreciate everyone's knowledge on this forum. I'm relatively new to boat ownership and am tackling most of the maintenance on my boat myself for the first time, with guidance from YouTube and this forum. I own a 1984 Hunter 31...

At the end of last season, while motoring back to my slip from a nice afternoon sail, I noticed a loud repetitive knocking sound originating from below. The frequency of the knocking seemed to follow the throttle - as I increased the throttle, the frequency increased; decreasing the throttle...