I have a 1987 Pearson 303. Yanmar 16. I get a lot of diesel fume smell below when under power. The engine room is sealed well. I also noticed that I do not have any ventilation anywhere on the stern. It seems to me that I should mount an intake and exhaust vents on the stern and attach an inline fan to the exhaust with the hose down near the motor.
When I get back to the slip I always have to let it air out.
is the engine room too well sealed?... where does the engine get fresh air? I wonder if you have an exhaust leak? With the engine running try holding a narrow piece of TP around the exhaust joints...dies it blow away at some point? You shouldnt smell that much unless you are heading downwind alot... an engine room exhaust fan is a good idea for sure, but you may have another problem.....
__________________ "I spent most of my money on Booze, Broads and Boats. The rest I wasted" - Elmore Leonard
Raycoker, by saying vents on the stern , I hope you mean stern deck and not the transom. Putting vents in the transom would almost guarantee water in your engine room sooner or later. You might also want to put the hoses so that if any water got in, it would go against the hull rather than your alternator or starter, etc. I hope this helps._____Grant.