I just had my boat have a bit of problems when engaging in forward but not reverse. I adjusted the shift cable and all is fine now. If that's not your problem it might be your thrust bearing wearing out and you'll need to get that rebuilt. This is assuming you have a typical two shaft transmission and not a hydraulic.
06-05-2014 10:08 PM
Re: Beneteau 40 transmission problem
You posted this under "Beneteau". This reduction gear is found in thousands of boats of all makes. You will have no shortage of responses (some may even be worthwhile) if you post under "gear and maintenance" sub-topic "diesel engines".
Works in reverse. When in forward it does not engage or only weakly. Then get revs up to about 1200 and it slams into gear. The cables are fine and the lever on the side of gear box moves easily and to the fullest extent.
Sounds like truly an internal problem. The oil (SAE 30 HD) is a bit black but doesn't smell burnt.
A friend suggests flushing numerous times with say SAE 10 to see if anything is stuck or "plugged". I've no idea what's inside!!