Air-Oil Separators

I am considering installing an air-oil separator in my 172H (Cont
O-300d). I have spoken with Airwolf who say theirs will work well and
is ALMOST STC'd but they "will provide the required paperwork to make
it legal until the STC comes thru" (whatever that means).
I also spoke with Aircraft Spruce who say the M-20 is the one for my
plane and it is already approved.
Airwolf is $495 M-20 is $360

Any suggestions/PIREPS/considerations/anecdotes appreciated.

As I understand it, the only benefit of an air/oil separator is to keep the
belly of the plane clean. In reality, what it does is concentrate all the nasty
water and acids the plane normally produces as combustion byproducts and send it back
into the engine. I wouldn't install one on my plane for this reason... even though
it's got a dirty belly.

-Cory

wrote:
: I am considering installing an air-oil separator in my 172H (Cont
: O-300d). I have spoken with Airwolf who say theirs will work well and
: is ALMOST STC'd but they "will provide the required paperwork to make
: it legal until the STC comes thru" (whatever that means).
: I also spoke with Aircraft Spruce who say the M-20 is the one for my
: plane and it is already approved.
: Airwolf is $495 M-20 is $360

: Any suggestions/PIREPS/considerations/anecdotes appreciated.


--

************************************************** ***********************
* Cory Papenfuss *
* Electrical Engineering candidate Ph.D. graduate student *
* Virginia Polytechnic Institute and State University *
************************************************** ***********************

wrote:

As I understand it, the only benefit of an air/oil separator is to keep the
belly of the plane clean. In reality, what it does is concentrate all the nasty
water and acids the plane normally produces as combustion byproducts and send it back
into the engine. I wouldn't install one on my plane for this reason... even though
it's got a dirty belly.


Interestingly, the upcoming Aviation Consumer has an article on this.
According to their web teaser it looks like they agree with you, but my
print copy hasn't come yet so I haven't read the whole article (I know I
can read it online as a subscriber, but what's the fun of getting the
print version in the mail if I've already read everything in it online?)

The Airwolf will work on your 0300-D with wet vac pump.
You need two M-20's to do the same job - one for oil & one for wet vac pump.
Have you cecked out the photographs pf the M-20 split in half to show what
is inside it?
You'll find them on the Airwolf website

HTH

Tony
C-GICE

In article .com,
" wrote:

I am considering installing an air-oil separator in my 172H (Cont
O-300d). I have spoken with Airwolf who say theirs will work well and
is ALMOST STC'd but they "will provide the required paperwork to make
it legal until the STC comes thru" (whatever that means).
I also spoke with Aircraft Spruce who say the M-20 is the one for my
plane and it is already approved.
Airwolf is $495 M-20 is $360

Any suggestions/PIREPS/considerations/anecdotes appreciated.

On Thu, 16 Jun 2005 12:32:19 -0400, xyzzy wrote:

wrote:

As I understand it, the only benefit of an air/oil separator is to keep the
belly of the plane clean. In reality, what it does is concentrate all the nasty
water and acids the plane normally produces as combustion byproducts and send it back
into the engine. I wouldn't install one on my plane for this reason... even though
it's got a dirty belly.


Interestingly, the upcoming Aviation Consumer has an article on this.
According to their web teaser it looks like they agree with you, but my

If that is their conclusion I'm afraid I won't miss the publication.

I have one of the Deshannon Air oil separators on my Deb and the oil
stays quite clean until 15 or 20 hours. All that *stuff* boils at a
lower temp and does not seem to collect. Beside that I have never had
to add oil except during the breakin for new rings (It had soft rings)

Currently at 25 hours The oil isn't down hardly far enough to measure.

Yes, I have a wet pump so without the air/oil separator it'd be a real
mess.

If I purchased another plane one of the first things I'd do would be
to add an air/oil separator if it didn't have one.

The engine is getting fairly close to TBO so it's doing well even
though I've not flown a lot the past two years.

Roger Halstead (K8RI & ARRL life member)
(N833R, S# CD-2 Worlds oldest Debonair)
www.rogerhalstead.com
print copy hasn't come yet so I haven't read the whole article (I know I
can read it online as a subscriber, but what's the fun of getting the
print version in the mail if I've already read everything in it online?)

Roger wrote:

On Thu, 16 Jun 2005 12:32:19 -0400, xyzzy wrote:


wrote:


As I understand it, the only benefit of an air/oil separator is to keep the
belly of the plane clean. In reality, what it does is concentrate all the nasty
water and acids the plane normally produces as combustion byproducts and send it back
into the engine. I wouldn't install one on my plane for this reason... even though
it's got a dirty belly.


Interestingly, the upcoming Aviation Consumer has an article on this.
According to their web teaser it looks like they agree with you, but my


If that is their conclusion I'm afraid I won't miss the publication.

I have one of the Deshannon Air oil separators on my Deb and the oil
stays quite clean until 15 or 20 hours. All that *stuff* boils at a
lower temp and does not seem to collect. Beside that I have never had
to add oil except during the breakin for new rings (It had soft rings)

Currently at 25 hours The oil isn't down hardly far enough to measure.

Yes, I have a wet pump so without the air/oil separator it'd be a real
mess.

They said if you have a wet pump then it's a good idea.