Yanmar Diesel Blowby issue

[dtmartin82]

We have a 31TE with a Yanmar 6LY2A-STP FWC 440 6 cyl diesel that we purchased this winter. We were running it this weekend and noticed smoke in the cabin. (like smoke in a bar)..Blowers removed this with no problem but had to keep the blower running to keep it cleared. Our mechanic suggested researching Walker Air Sep for the blowby. Has anyone else ran into this problem. We had the boat gone over and checked out but the more I research the more confused I get. HELP!!! any comments, suggestions or similar problems and what worked for you...

[jleonard]

There could be a few reasons. Before I added an Airsep (and maybe mask the issue) I would check a few things first.
Not all that familiar with Yanmars, there has to be a crankcase vent somplace. It probably leads to the turbocharger intake. Make sure that is clear,clean and functioning properly. Make sure the oil level is correct (too full can cause excessive blowby).
I think also most or all diesel engine manufacturers have blowby specifications. I know Cummins has a detailed procedure for measuring blowby. I would do this or have it done to learn the health of the engine.
There is also a "seat of the pants" blowby test that some experienced mechanics use where they remove the oil fill cap and get a feel for the pressure comming out. You'd have to compare to another similar engine.

[dtmartin82]

Thank you so much for the response. That was my feelings on the Airsep also. The mechanic had gone over all of that previously but I think I will have him check it out again. Also for a possible seal that didn't seat or is somehow now fitting properly. The engine only has 1000 hours on it, but is 10 years old. Actually bought it up in your neck of the woods. Thanks again.