During the recent sale of my boat the surveyor commented that the 14X14 prop that is class legal is the wrong prop for the boat. This has been confirmed by Bengt Johannson in discussions with Martec. With the current prop it is difficult to get the engine to 80% of max as encouraged by Yanmar. I believe this leads to carbon buildup in the cylinders. If the rings contract during the cold winter temps the carbon prevents them from returning to the cylinder walls. This can lead to cylinder damage. Happened to be about 10 years ago and had to have the engine rebuilt.
The
J30 Class needs to look into this and see if a prop change is in order. Would help extend the life of your old engines.
Larry Christy
DA KINE (Sabreline 42)
