[C320-list] no forward or reverse

[DrShoffner at aol.com]

I just attempted to go for a sail, but when I cast off into the creek  I had 
no forward or reverse.  It will go into gear, but the engine just  won't rev.  
The shaft spins freely in neutral.  I was able to drop the  hook, and a Sea 
Tow boat was just dropping off another boat and was nice enough  to take me 
back alongside my dock at no charge.
 
I assume I've got a transmission problem.  My boat is hull #171 with  the 
Perkins M30 and only 311 hour.  Any other thoughts before I call the  mechanic?
 
Mike