O-200 Crankcase Breather Line

VF84Sluggo

Filing Flight Plan
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VF84Sluggo
I have an Aeronca Champ, O-200 in it. I'm getting tired of the oily belly, oil residue on the right gear strut and brake line.

As is known, and thus to not re-kindle a debate, the opinions on air/oil separators in the breather line vary. But best I can tell the "varying" seems to be over whether or not to return the liquids back into the engine. So, all I'd really like to do is just be able to capture the liquids in the line, then drain it out periodically.

Any thoughts/suggestions? Thanks in advance!
 
We had one of those Airwolf air/oil separators on a 172. It made almost no difference in the amount of oil on the belly.

And no, you don't want to be returning condensed water back into the case. An oil belly is better than a corroded engine.

The breather fitting on the small Continental crankcase is normally a special fitting, but I have found them replaced with a plain elbow. Here's an article by a homebuilder: https://www.wittmantailwind.com/diy-continental-o-200-air-oil-separator/

And a pic of the Continental fitting:
images


From http://sky4buy.com/Breather-elbow-for-small-Continental-engine-like-633182-261697416354/0840
 
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Thanks, Dan. My thoughts, too, re. returning the breather tube contents back into the engine.

Just wondering if an air/oil separator gizmo could be installed where, instead of the return line being routed to an engine fitting, it emptied into a container of some type. This way the slime gets kept off the belly, AND out of the engine.
 
The stock breather fitting for O-200 is the elbow without the tube extension. Continental modified the stock elbow by soldering/brazing/welding (?) a tube onto the elbow similar to what the earlier picture shows and installed it on Cessna Aerobat. For a couple hundred bucks you too can purchase an "Aerobat oil breather fitting" and replace the plane elbow.
 
The stock breather fitting for O-200 is the elbow without the tube extension. Continental modified the stock elbow by soldering/brazing/welding (?) a tube onto the elbow similar to what the earlier picture shows and installed it on Cessna Aerobat. For a couple hundred bucks you too can purchase an "Aerobat oil breather fitting" and replace the plane elbow.

The fitting predates the Aerobat. Some A- and C- model engines had it. See https://www.google.ca/url?sa=i&rct=...aw2cDmbnRJVQ6JMIj3yLA66p&ust=1545860463008775
 
The breather fitting on the small Continental crankcase is normally a special fitting

And a pic of the Continental fitting:
images
This is not true, no 0-200 came from the TCM factory with a special fitting.
the AeroBatt fitting was installed only in the C-150 Aerobat, at the Cessna factory.

many 0-200 in various aircraft have been retro fitted with the Aerobat fitting.
This fitting when retro fitted to 0-200 will reduce the oil discharge but it won't stop it.
In my last 0-300-A the owner installed a aerobat fitting to see if it would help, and thus far it has.

best way to stop the oil on the belly is a catch can, there are several on the market.
 
actually the O-200D engine as delivered new to me (2016) from TCM had the so-called aerobat breather installed
 
actually the O-200D engine as delivered new to me (2016) from TCM had the so-called aerobat breather installed
nice to know, the 0-200-A is what this thread was about.
I talked to my latest 0-300 rebuild owner ad he says the fitting doesn't make any difference. but in his case every thing in his engine is new.
 
Her little sister the c85 im finding to be the same way!
This engine has well over 500 hours now and doesn't leak a drop, build them right and they won't leak.
 

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This engine has well over 500 hours now and doesn't leak a drop, build them right and they won't leak.

I thought we were discussing drips out the vent tube...
 
How much oil is in it? In my limited experience with the O-200 seems to have a place it likes to run and if you put more than that in it will just blow it out till it gets to that point then it seems to hold there.
 
Far better than the 70 year old O-200.
 
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