Has anyone installed an air/oil separator that collects to a container. This would prevent the breather mixture from being returned to the engine (acid, oil, water mixture) and also prevent a greasy belly. I assume the container would need to be emptied after X number of flight hours. If anyone has done this can you provide pictures. Was it worth the effort or is this overkill? Thanks, Dean
Van's Air Force
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Air/oil Separator engine breather
- Thread starter Dean
- Start date
Collector
I have one but I plan to remove it. It accumulates a quarter cup or less between changes. And, I still get streaking on the belly. I blame my air/oil separator though. It is an "expiremental only" model as offered by Spruce. Overall, disatisfied enough with the combo that they are both coming off.
I too woudl like to hear if anyone has one that actually works.
I have one but I plan to remove it. It accumulates a quarter cup or less between changes. And, I still get streaking on the belly. I blame my air/oil separator though. It is an "expiremental only" model as offered by Spruce. Overall, disatisfied enough with the combo that they are both coming off.
I too woudl like to hear if anyone has one that actually works.
Wicked Stick
Well Known Member
This is interesting, perhaps it is dependent on the type/make/setup of them.
We have one on our RV-4 (co-owned) and it seems to work rather well.
Especially so in the winter months for removing water from the system as well as oil.
It is a "home made" ...er...experimental
setup. It's rather simple but seems to work. It's simply a 1qt square container with a screw cap on it. the cap has two fittings on top, one from the breather port of the engine, and the other simply routes the hose down and out the bottom of the cowl.
We do see a slight amount of oil on the belly between oil changes, but it's far less than what I've seen on other aircraft I've owned that didn't have it.
Here's a link to a picture of it: http://www.rivetbangers.com/g2data/forums/albums/users/wickedstick/oilwater_sep.jpg
We have one on our RV-4 (co-owned) and it seems to work rather well.
Especially so in the winter months for removing water from the system as well as oil.
It is a "home made" ...er...experimental
setup. It's rather simple but seems to work. It's simply a 1qt square container with a screw cap on it. the cap has two fittings on top, one from the breather port of the engine, and the other simply routes the hose down and out the bottom of the cowl.We do see a slight amount of oil on the belly between oil changes, but it's far less than what I've seen on other aircraft I've owned that didn't have it.
Here's a link to a picture of it: http://www.rivetbangers.com/g2data/forums/albums/users/wickedstick/oilwater_sep.jpg
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I have always had an oil separator. It is the 'homebuilderers' special from Spruce. I have been through 2 modifications after running it stock. There is still blowby but less than there is without an oil separator. I clean the belly twice a year.
The only Oil Separator that I have seen (on one airplane) that does not have oil on the bottom has a Christen Inverted Oil system on it. The Christen Oil Separator sells for $384.95 at Spruce (P/N: 08-06740). I do not know if the owner cleans the bottom after every flight but the bottom of his RV-4 is always clean.
The only Oil Separator that I have seen (on one airplane) that does not have oil on the bottom has a Christen Inverted Oil system on it. The Christen Oil Separator sells for $384.95 at Spruce (P/N: 08-06740). I do not know if the owner cleans the bottom after every flight but the bottom of his RV-4 is always clean.
I am taking mine off for it acts as a condensor more than anything. Water collects inside and runs back into the engine via the return tube. I guess if I had some heat added to it the thing would work fine but in an RV4 there is not enough room to put it close enough to the heat to keep condensation from happening.
Anyone just run it into the exhaust? I have seen some aerobatic airplanes running it into the exhaust, granted they have the christen system but I thought I would ask.
Anyone just run it into the exhaust? I have seen some aerobatic airplanes running it into the exhaust, granted they have the christen system but I thought I would ask.
gmcjetpilot
Well Known Member
Ditto
Oil gets on the belly from those little drips & drabs of oil that fall into the bottom of the cowl while you work on your plane or from little leaks.
Save the money, weight and clutter under the hood. Speaking of money many of these top secret space age miracles (they claim) are just a CAN with a tube, which they charge $300 for.
As you point out the acid & crud that comes out the bottom of a oil/air separator is not something you want going back into the engine. Also why save it in a seperate container (which is what I did for a while). Just do as Van has recommended per plans for decades, run it to the top of the hot exhaust pipe and burn it off.
One exception. If you do lots of near Zero-G acro, with occasional light excursions into negitve-g's, the air/oil separator may keep a little more oil off the belly. However most "gentleman's acro" is done at +0.3 g's or above. As far as negative-g's, when you're in turbulance you bounce into negative all the time, right. It's just sustained inverted that's a no-no.
Ditto. You will read much hype and propaganda from the people that sell air/oil separators, but a healthy Lyc blows out very little from the breather. A lot of air oil separators where for wet vacumn pumps that did need a separator.Mel said:
Oil gets on the belly from those little drips & drabs of oil that fall into the bottom of the cowl while you work on your plane or from little leaks.
Save the money, weight and clutter under the hood. Speaking of money many of these top secret space age miracles (they claim) are just a CAN with a tube, which they charge $300 for.
As you point out the acid & crud that comes out the bottom of a oil/air separator is not something you want going back into the engine. Also why save it in a seperate container (which is what I did for a while). Just do as Van has recommended per plans for decades, run it to the top of the hot exhaust pipe and burn it off.
One exception. If you do lots of near Zero-G acro, with occasional light excursions into negitve-g's, the air/oil separator may keep a little more oil off the belly. However most "gentleman's acro" is done at +0.3 g's or above. As far as negative-g's, when you're in turbulance you bounce into negative all the time, right. It's just sustained inverted that's a no-no.
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