Installed crankcase ventilation system, finally!

Hard to believe it took me this long to do it, but after years of putting up with a gaseous bilge and nasty oily residue, I finally got around to installing a positive crankcase ventilation system on Aeolus. One would have thought that this system, required on all vehicles since about 1863, would have been standard on the Universal 5432 aboard Aeolus, but alas, it was not. Seems that marine diesels were neither required nor was it common practice to do this back in the 80's.

There is no particular concern in doing this installation as again it has been common practice on all engines for many decades. Even my lovely 1978 Mercedes 300D, one of the finest machines ever built, has a positive crankcase ventilation system on it. Though one of the main reasons for this on cars is smog related, boats lack the fresh air around the engines of cars and thus we sailors have other pressing reasons for the system. 

The problem became very acute when I installed a cabin heater that drew air from the bilge area and it therefore blew out the oily air that the crankcase was venting into the bilge. I became really tired also of wiping oily residue off of all the surfaces, as the outlet for the old hose put it down near the bottom of the oil pan, but the suction of the intake manifold pulled a fair amount of that air up and around the engine. That is, besides hot air rising.

View of the crankcase ventilation system installed. Trace the hose from the air filter back to the crankcase.

The solution was quite simple with my K&N filter. I bought the appropriate diameter of high quality hose and ran it from the existing outlet for the crankcase to a plastic fitting I pushed through a drilled hole on the filter. With a hose clamp on the hose and fitting, there is no risk of it being sucked internally back into the intake manifold.

Let me say, I haven't done full sea trials yet, but just running the engine at the dock for a few minutes I could smell a noticable reduction in the oily vapor that usually permeates the engine compartment. I would highly encourage any other sailors out there with diesels like mine that lacked this system to make the quick and easy change.