---------------------------------------------------------- Commander-List Digest Archive --- Total Messages Posted Tue 02/21/06: 5 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 07:33 AM - Re: air/oil separators (Moe) 2. 07:52 AM - Re: air/oil separators (Moe) 3. 09:38 AM - Re: air/oil separators (steve2) 4. 11:40 AM - Re: air/oil separators (RRamm52@cs.com) 5. 08:05 PM - Re: air/oil separators (BillLeff1@aol.com) ________________________________ Message 1 _____________________________________ Time: 07:33:37 AM PST US From: "Moe" Subject: Re: Commander-List: air/oil separators --> Commander-List message posted by: "Moe" Bill, Where did you mount the M20's on the 680F(p)? Did the scavenge lines go down to the oil return lines that go to the cylinder heads?. This might be a little easier for me than getting a one time field approval on my "home made" separators. Thanks very much for the help, as I just can't seem to keep the top of the engine nacelles from dripping oil no matter how tight the engines are. Regards, Moe N680RR 680F(p) ----- Original Message ----- From: Sent: Monday, February 20, 2006 10:13 PM Subject: Re: Commander-List: air/oil separators > --> Commander-List message posted by: BillLeff1@aol.com > > I have M20's on my 560F and they work great with 2 1200 hour engines. We > also put 2 on a 680FP and they are working well. However, on the 680FP we had > to rig up a scavenging system to get the oil back to the engine due to the > volume of oil they collected. That took a while to figure out. We are preparing > to put a set on a 500S next. The M-20 STC does cover the Aero Commander. > > Bill Leff > > ________________________________ Message 2 _____________________________________ Time: 07:52:51 AM PST US From: "Moe" Subject: Re: Commander-List: air/oil separators --> Commander-List message posted by: "Moe" Chris and Roland, I have read with interest Chris' comments on returning water vapour to the engine when an oil separator is used. This could very well be a concern as the steam would ordinarily go out of the breather tube (when the oil temp goes up to 212) instead of collecting on the separator screen and returning to the engine oil. Here in sunny Southern California where it never rains and the humidity is generally pretty low this may not be a concern (except that we are by the ocean). Thanks for bringing this up. Regards, Moe N680RR 680F(p) ________________________________ Message 3 _____________________________________ Time: 09:38:10 AM PST US From: "steve2" Subject: Re: Commander-List: air/oil separators --> Commander-List message posted by: "steve2" The more I learn the more I think it's a bad idea to recover the vapors and contaminants leaving the crankcase. I did have an oil seperator freeze up on me warming up in a TU-206. It was negative something or other, so real cold. But it wasn't until that day I really knew there was nothing on the gauges to tell me anything was wrong. Preheat warmed the engine enough, but not the seperator. Always suprised how much water gets generated and cycled through aircraft engines.... Steve ----- Original Message ----- From: "Chris Schuermann" Sent: Monday, February 20, 2006 8:14 PM Subject: Re: Commander-List: air/oil separators > --> Commander-List message posted by: Chris Schuermann > > > Thought I'd add one more "opinion".... > > After having an airplane with and without a separator, cutting one apart > to see how it works, and thinking about it quite a bit, I came to the > conclusion that I'd rather have some oil blown out than have a > separator. My logic is that the separator not only condenses oil mist > and returns it to the engine, it also does much the same for oil-trapped > moisture. I felt that it was actually noticable visibly with my > airplane and became concerned that I was going to cause rust/corrosion > formation. Probably a non-issue if you fly every day, but for my once > a week flying it was a concern. > > chris > > > ________________________________ Message 4 _____________________________________ Time: 11:40:24 AM PST US From: RRamm52@cs.com Subject: Re: Commander-List: air/oil separators --> Commander-List message posted by: RRamm52@cs.com Hi, Roland As you know, I flew her for 100 hrs or so and I believe that a good set of seperators would help considerably, also......she's a great plane...:) [vbg] Rob In a message dated 2/20/2006 8:34:20 PM Central Standard Time, amg@nc.rr.com writes: > Moe,. > > I have a straight 500 (0540's) 250 hp. and I'm referring to the > engines. I'm adding about 1 quart of oil per 1 1/2 hours per engine, but > a lot of it is on the ground . This tells me that it is blowing out all > the time it is flying. Maybe I have excessive blow by, but compressions > are ok. Engines are 1100 hrs each app. > > Thanks, > > Roland ________________________________ Message 5 _____________________________________ Time: 08:05:42 PM PST US From: BillLeff1@aol.com Subject: Re: Commander-List: air/oil separators --> Commander-List message posted by: BillLeff1@aol.com Moe, I mounted the M-20's on brackets I made and hung them from the exhaust chutes On the 560F I drained them into the rocker drain tube. On the 680F, the IGSO-540 has too much case pressure to allow good draining from the M-20's. I recommend that you plumb the drain into the inlet side of the vacuum pump. Loravco Aviation (in Bloomington, IL) figured out another way that also works but I prefer using the vacuum pump. Bill Leff