tried LOP for the first time - have some questions

[jlunseth]

Quote: bd32322

thanks jetdrive - yeah my engine is drinking oil at about 1 quart every 5 hours or so - hoping it comes down with LOP - altho like you said I am not sure of the correlation

[John Pleisse]

Hey 201'er....... go do a test flight with your mechanic or a pilot A&P you trust. Getting information from Mooneyspace and Mooney-Tech shouldn't factor heavily in your decision making.

And re a post from another gentleman:

yeah my engine is drinking oil at about 1 quart every 5 hours or so - hoping it comes down with LOP -

It will not with LOP (I hope some other way...).

[Shadrach]

Quote: N4352H

Hey 201'er....... go do a test flight with your mechanic or a pilot A&P you trust. Getting information from Mooneyspace and Mooney-Tech shouldn't factor heavily in your decision making.

And re a post from another gentleman:

yeah my engine is drinking oil at about 1 quart every 5 hours or so - hoping it comes down with LOP -

It will not with LOP (I hope some other way...).

[KSMooniac]

Quote: N4352H

Hey 201'er....... go do a test flight with your mechanic or a pilot A&P you trust. Getting information from Mooneyspace and Mooney-Tech shouldn't factor heavily in your decision making.

And re a post from another gentleman:

yeah my engine is drinking oil at about 1 quart every 5 hours or so - hoping it comes down with LOP -

It will not with LOP (I hope some other way...).

[John Pleisse]

Quote: KSMooniac

Actually, flying LOP can reduce oil consumption IF the bulk of the consumption is caused by blow-by around the rings.  Peak pressures in the cylinders are much higher while ROP, and thus more prone to blowing oil out due to pressurization of the crankcase.  Flying LOP will reduce this behavior and reduce apparent consumption if that is the cause.  If the engine is just leaking oil somewhere, then not so much of course.

Getting education from these lists can be much more valuable than talking to an A&P that doesn't fully understand the nuances of mixture management.  There is no requirement for an A&P or IA to know any of it, in fact.  Many mechanics (and instructors for that matter) are very ignorant on this topic and can only parrot techniques that were passed on to them "because we've always done it this way."  For the educated pilot paying the bills, it is very prudent to get educated on this topic.

I concur that 201er's understanding of the facts and the difficulty rectifying Lycoming's public position is correct.  LOP ops are very simple, and offer a much greater detonation margin than 50 ROP, as well as much kinder treatment to the engine components.  The only downside is the loss of speed when flying a normally aspirated plane, but efficiency increases and it saves a lot of money in fuel alone while offering the potential to save substantial money at overhaul time too.

[John Pleisse]

.

[201er]

Quote: JimR

I do believe that LOP operations have improved my consumption a bit, but where I can really see an improvement is in the number of hours that it takes the oil to darken. It used to just take a couple of hours. Now operating LOP it takes more like 15 or maybe even 20 hours.

Jim

[KSMooniac]

It is quite good... it indicates that there is far less blow-by past the rings.  Oil darkens because of the combustion by-products (as well as dirt and such) and less blow-by means slower contamination.  This is positive proof that the peak pressures in the cylinder from LOP ops are much lower than for ROP ops, even with equivalent power settings.