AirSep for Marine Transmission?

[Taras]

Hey all,
I have airseps on my 3306 Cat mains. They work great to keep the engines clean of any blowby oil mist.
I just finished cleaning all the oil off my Cat Marine Transmissions (model MD-509) and I am wondering if there is a airsep type product that can replace the "vent cap" on these transmissions. I'm trying to prevent oil mist that gets on the trannys overtime. Real pain to clean these up and paint them. Now I just want to keep them clean.
I have contacted AirSep (Walker) and they don't see to have a solution. Any thoughts on safety capturing the oil from the vent cap?
I have some photos below.
Thank you for any input!
Taras

 

[kapnd]

You could make up a “puke bottle” system with a collection bottle at a low point, and end the tube close to the engines air intake, but first, have you considered that you may be overfilling the transmission sump?

 

[rslifkin]

Another option would be to cut a donut of oil absorbing pad to slip over the vent and change it out periodically. That should catch most of what comes out before it hits the paint.



Definitely confirm fluid level, however, as most transmissions shouldn't vent much during normal use (unless those just have a poor vent design).

 

[bayview]

surprising that your trannys vent oil. Are you filling as the manual directs?

 

[Taras]

Great question regarding the oil level. Yes, the dipstick is right on the money. Its definitely not overfilled. Just heard back from AirSep and they can build me a system but its $500 per transmission (I have twins). Just thinking I could make something up that could save that boatbuck. Let me know if anyone has ideas. I expect to see the product that Airsep is proposing as soon as they email me a picture. I'm thinking maybe I can copy the design somehow.....

 

[Comodave]

I had a mechanic when I bought a boat with twin Detroits that made a simple Air Sep for me. He took a simple fuel filter canister and routed the air box vents to the filter. Had the blow by go in one side and left the other side open to bent the air out. The oil would stick to the canister and eventually I would drain the oil, maybe every 50 hours or so. They worked very well and were cheap.

 

[jleonard]

I made this to catch the yuck from a Cummins diesel. This is PVC pipe, but could be any container. Hose going in on one end, going out on the other with hose end near an engine vent. Piece of oil diaper inside to collect the oil residue.
This worked great in my application. Something similar should work for you.

 

[C lectric]

Often just adding a pipe nipple to the entry hole and extending the actual vent up will help. A larger piece of pipe above the first nipple should also help capture any oil. The larger pathway will slow any froth or fumes so they collect on the pipe insides.

Or as suggested adapt/make a filter and lead a hose over to it.