ROP vs LOP in a 66 M20E

[Hedge]

I have been flying my 66M20E for out three months now.  I have been flying ROP as that is what I have been taught.  Peak temperature and enrichen to 50 deg F below peak.

 

I see people flying LOP and I am trying to figure out why and won't this kill your engine?

 

If you do fly LOP, how do you do it?

 

For long cross country trip 500+ NM trips, I use 23 MP with 2400 RPM at 8-10K.  I am trying to be as efficient as possible.

 

Mark

[DS1980]

^{Search for a topic called "New owner leaning question." This is a great start.}

 

^{Next, and more important,  what altitude do you fly at? 50 ROP is the worst place to run an engine if producing more than 65% power. If always at 8-10K feet, you're ok.} 

 

^{To answer your other questions, the reason why is two fold. First, it produces lower CHTs and is kinder on the engine. The second is it allows us to operate at a mixture called best economy. This allows for about a 5% reduction in speed for a 30% savings of fuel.}  

 

^{It won't kill your engine because you are asking it to produce less power. The engine doesn't care how much fuel it is burning, as long as it has balanced fuel to the cylinders to eliminate roughness and as long as it is operating between mixtures that are too rich to burn (8:1) and too lean to burnm (18:1).}

 

^{Once you read the thread, let us know of questions.}

[PTK]

Hedge, here are three links for you:

http://www.eaavideo.org/video.aspx?v=2274677932001

http://www.eaavideo.org/video.aspx?v=2534345030001

http://www.eaavideo.org/video.aspx?v=2789444176001

I'd recommend you watch them in that order as the concepts build. They'll fall in place and make sense.

You will learn how to extract the most available power out of your engine and prop, maximize the airplane's efficiency and keep the engine happy.

Good luck!

[mikerocosm]

To the very sage advice on watching Mike Busch's webinars suggested above by PTK, I would add:

 

http://www.avweb.com/news/pelican/182179-1.html?redirected=1

http://www.avweb.com/news/pelican/182176-1.html?redirected=1

http://www.avweb.com/news/pelican/182583-1.html?redirected=1

http://www.avweb.com/news/pelican/183094-1.html?redirected=1

 

In fact, just scan the articles by John Deakins at 

 

http://www.avweb.com/news/pelican/182146-1.html?redirected=1

 

for a rich body of literature about running our engines and the many myths that people have believed in the absence of actual data provided by modern instrumentation. Then decide for yourself.

 

Best regards, and best of luck!

 

Mike

[Steve65E-NC]

Mark,

Do you have a multi cylinder monitor installed? I installed a JPI EGT 700 about 20 years ago and consider it my most critical and valuable instrument. I fly LOP all the time at 65% and below. I understand that LOP would be much easier if I had fuel flow installed and recommend that also. If I am flying at 75%, I try to keep ROP spread from first to lean at 100 degrees F.

[pinerunner]

All of the above advice is good, especially the suggested videos. 

 

If I had a plane with no engine monitor, I would start with leaning for taxi. This helps minimize lead deposits which can happen when the engine is running very rich and very cold, as in right after startup.  If you truly lean far enough the engine won't be able to develop takeoff power so you can't accidentally forget and takeoff with it leaned.  Many who wouldn't dream of trying LOP operations do this and its easy. The only danger is if you're too shy about it, lean just a little for taxi, and forget and take off with it set just wrong.

 

I think the scare stories that you get from some mechanics arise from people who were too cautious and leaned just a little.

 

Watch those vids.

[Skywarrior]

<settling in with popcorn>

[Hank]

All of the above advice is good, especially the suggested videos. 

 

If I had a plane with no engine monitor, I would start with leaning for taxi. This helps minimize lead deposits which can happen when the engine is running very rich and very cold, as in right after startup.  If you truly lean far enough the engine won't be able to develop takeoff power so you can't accidentally forget and takeoff with it leaned.  Many who wouldn't dream of trying LOP operations do this and its easy. The only danger is if you're too shy about it, lean just a little for taxi, and forget and take off with it set just wrong.

 

I think the scare stories that you get from some mechanics arise from people who were too cautious and leaned just a little.

 

Watch those vids.

I typically lean my C about 2/3 to Cutoff for ground operations, and my plugs look really good every time I pull them. I have not yet been able to run LOP, but carbs are different. Be careful, though--I did this with a friend's Cessna and the engine quit after landing and I coasted off the runway!

[DS1980]

<settling in with popcorn>

Why not help?

[David Brown]

Hedge, we were all taught a lot of wrong things, and without knowing better we all accepted it.

 

The education path is a fantastic one. http://www.advancedpilot.com

 

Money back guarantee. And what is funny is it is not my money!