oil separators

gmpaul · #1 12-10-2009, 06:00 PM

After just finishing my annual and thinking about all the cleaning of the firewall and belly, there has to be a better way. I asked around the airport if there was anyone familiar with oil separators and did they really help. I found one fellow that had one on his 172 and he is a firm believer in his. Has anyone used one on their RV? I was thinking about trying to make one because the price of the Airwolf is so expensive. It would be great if you could put in 8 quarts, go fly and come back with 8 quarts in the crankcase, instead of oil all over the belly and firewall. Has anyone tried an oil separator or found a better way?

Thanks,

GP

USCANAM · #2 12-10-2009, 06:06 PM

I only fly with 6 quarts in the case.
You'll see a difference
Jack
RV9A
157 hours

Garage Guy · #3 12-10-2009, 06:44 PM

There are some other threads on the topic. Here's one:

http://www.vansairforce.com/communit...ad.php?t=51286

--Paul

Bavafa · #4 12-10-2009, 06:55 PM

I have installed it on my engine and very happy with it. I fly with 8 qt. and have yet to see any oil on the belly. Just some residue from the exhaust, that's it. I bought mine from Vans which I thought was rather pricy, but now I am happy I did.

Good luck

scsmith · #5 12-10-2009, 07:10 PM

Many oil separators are designed to allow drain-back of the collected oil mist back into the engine. Some have argued that this process puts back a bunch of bad stuff - at a minimum, it puts water back - and may have other blow-by components that are better blown out than returned to the crankcase.

Some oil separators store the collected oil/water/stuff, and you have to empty the tank periodically.

Most of us have found that if you keep your crankcase filled just to 6 quarts, and you direct the oil vent onto one of the exhaust pipes, the belly stays pretty clean without any oil separator.

rvbuilder2002 · #6 12-10-2009, 09:49 PM

Quote:

Originally Posted by scsmith

Many oil separators are designed to allow drain-back of the collected oil mist back into the engine. Some have argued that this process puts back a bunch of bad stuff - at a minimum, it puts water back - and may have other blow-by components that are better blown out than returned to the crankcase.

Some oil separators store the collected oil/water/stuff, and you have to empty the tank periodically.

Most of us have found that if you keep your crankcase filled just to 6 quarts, and you direct the oil vent onto one of the exhaust pipes, the belly stays pretty clean without any oil separator.

What Steve said....

There is really no reason to fly with 8 qts in the crankcase (unless you are flying from HI to CA like John J has done a few times). It is pretty common knowledge that the four cyl Lyc seem to spit very little oil if you keep the level around 6 qts.

Bavafa · #7 12-10-2009, 10:19 PM

I know every one agrees with the idea of having only 6 qts in the engine (with CS prop) is sufficient, but I wonder why Lycoming insist of 8 qts and indicates 6 qts is the minimum? I keep at max most of the times, first to make sure I am following the engine manufacturer recommended guild lines, if for no other reason but to keep my warranty in check. Another reason is what if you start with six qts and you have a bit of leak or burn or some thing in between trips then you surely would run out oil sooner, right?
With the oil-air separator I have had about zero of oil under the belly, so I think it is a good insurance for how little it cost compare to other things we spend on the AC.

Just my 2 cents

Ingo Weise · #8 12-10-2009, 11:56 PM

In the engine manual of our M20J Lycoming states that the minimum oil level for lubrication is 2 quarts. Everything above that might be needed for cooling, depending on OAT.

Regards

Flybuddy2 · #9 12-11-2009, 04:49 AM

Here's the answer, instead of separating and still allowing a lower percentage to hit the belly, this eliminates it. You just drain the oil residue at each oil change. I had this on my Velocity and had zero oil on the prop. The RV6 I just bought (and have only flown once) has the Vans oil separator on it and I'm swapping it out to this as soon as the order arrives from a/c spruce.
If anyone wants a used Vans separator for half price let me know.

http://www.aircraftspruce.com/catalo...nginecrank.php

Tom Martin · #10 12-11-2009, 07:07 AM

I built an oil separator this summer, using a couple of soup cans. It worked well but I was concerned about returning the collected oil back to the engine as I had heard all the stories about contamination,water, etc. I ran a plastic line below the cowling and tied it off. On regular intervals I drained the oil to see what it contained. It was absolutely clear and clean, and my next project is to add a return line to the engine.