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Jeff,

Consider for a moment...

The break-in process...

The objective is to wear in the cylinders and rings to the full extent of their travel... 

- for many hours...

-adjusting rpm periodically, moving the ‘step’ wear around.

-as cold as possible... Deep ROP

- Max MP... Low altitude, full throttle...

Under full power and max rpm... the travel is at the extremes....

if you use less then these two max settings, the wear occurs just short of the max distance possible. Leaving a step...

Then a few times a month you perform a T/O run using max rpm and full throttle... 

remember where that break-in step occurred?

chromed cylinders were known for exacerbating the step and caused a similar challenge...over time.

1) your descriptions indicate your break-in of new cylinders may not have happened properly.

2) your oil in the intake system needs to be figured out immediately... This one is too un-normal to wait on.  It might only be a hour job to know what is wrong...

3) 1 qt ever 8 hrs is safe for the family... a gallon in the same time, ...not so much....

4) Not knowing where the oil is leaking from, is essentially a sign that it could get worse in the middle of a flight leg.

5) Something seems to be hiding... a lot of work is going on to chase down missing oil over a long period of time... then you got the plane with the same problem, not fixed?

Ever have an engine run out of oil?  They break in miserable ways... (lawn mower experience)

so get on it... as a top priority.

Seek earnest discussions with your mechanic...

Break-in flights are best done with two people... one to fly, and your mechanic to observe... and decide on engine related parameters...

Flying near the ground, near Vne, and looking at instruments is highly not recommended for solo PP flights.

PP thoughts only, not a mechanic...

Best regards,

-a-

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Still more information needed. Sorry for all of these questions 

See if you can get an approximate  hours on those cylinders? Not a requirement to keep those times and nowhere did you state they where new only overhauled. Has there been any oversizing of the cylinders in the logs, It is possible that they have 4000+ hours on them, matching the engine TT 

Did they paint the cylinders, what color is on the top of cylinders? 

Was it the same person honing each time, did they really install new rings each honing. Receipts/ work orders, 

 part number of rings if available

get a compression  check see if you’ve got ring leakage in one or more, with that much oil usage it should be obvious 

Get a camera and look in your cylinders. 

Was straight  mineral oil used during each of the the break in processes ! Still being used? It should have been used until ring bedding in occurs.

 

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7 hours ago, MB65E said:

What oil and did the breaking in have any additives? 

personally, I’d start from scratch with mineral AS100M oil, no additives and run the snot out of it. 

Oil change <10hrs then repete until the oil stabilizes.

Run it at 6qts and note what’s on the belly. 

-Matt

That's exactly what I did when I bought it. Ran the piss out of it for 15 hours changed oil with Phillips mineral 20w50, did that 2 more times and I always run 6 quarts and my belly is perfectly clean

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Spuderman,

Try to stay to the technical details...

I get a bit lost when you state ‘run the piss’ out of something.

When you stated pretty clearly that you ran it it hard for take-off and climb...

Wide-open throttle and max rpm.

but you reduced the power setting for cruise.

Typical break in procedures. Are max rpm and max MP and max FF for several hours...

People will be watching CHTs for the status of the break-in process.

CHTs will decrease with the process under the same conditions...

The purpose of running WOT, max rpm, mixture in, is to keep a wear step from forming in one place that is shy of where the piston rings travel under take off conditions. The max mixture is for additional cooling during the high heat period of break-in...

other things to focus on are supplying some data regarding your engine operation.

Saavy has a good free way of doing that.

know about your oil rings... these are the rings on each piston that keep oil in its proper place. If they are old or broken or wrong, they won’t be working as expected...

Since the gallon of oil doesn’t seem to be exiting out the exhaust, and has appeared in at least one intake tube...

Wouldn’t it be smart to follow that clue to find the source of that oil...?

It would be near impossible to have oil go from the cylinders into the intake system... and run normally...

Post the jpi data as soon as practical. You have a few engineers around here that can help you, just by looking at your graphs...

Jpis usually save data from each flight since the day it was installed...

use white paper towels to catch samples from each of the suspected oil hide-outs... sniffle valve, air intake tubes etc... fuel will be much bluer than oil in those spots...

Let us know if you need help getting and posting data... graphs ... pics ... details....

Why wait?

Weird challenges don’t usually fix themselves...

you have at least one weird challenge going on... and it’s a serious one...

Is all of this making sense? List the things you get and the ones you don’t... somebody will try to help out...

PP trying to help out, not a mechanic...

Yes, small people take up a huge amount of time... you get a break when they go to school full time... don’t be in a rush... or we will talk about college bills... similar to daycare only worse... :)

 

Best regards,

-a-

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On 10/13/2018 at 7:54 PM, Spuderman1 said:

I've checked the accuracy of the dip stick and it is correct. But even if the dip stick isn't correct it still goes down 4 quarts every 10 hours of flight

You missed the point of verifying the dipstick accuracy, if in fact the dipstick was showing low,(meaning showing 6 quarts when you in fact have 7+ in sump) you could be overfilling your oil system.

Engines do not like to be overfilled with oil and will expel unneeded/unwanted oil and seek a level that IT wants not you. 360s 6 quarts would be pretty normal. 

how exactly did you figure out 2.5 quarts per 10 hours! Fill to 7, fly 4 hours, its at 6 , add a quart, fly 4 hours its at 6 again , add a quart, fly 2 hours,  its 6.5 add a 1/2 quart? 

People on MS are reallly helpful and smart, if you let them they will figure this out, but your going to have a lot of questions from several different people  that will need more exact,  specific answers. 

 

 

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This is not going to be an internet fix.   You need a good  inspection camera.   If oil is coming out of the seams of the engine, you can see it dripping.   If you can't find one of those options,  Then it is going out the exhaust past the rings.

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13 hours ago, Shiny moose said:

You missed the point of verifying the dipstick accuracy, if in fact the dipstick was showing low,(meaning showing 6 quarts when you in fact have 7+ in sump) you could be overfilling your oil system.

Engines do not like to be overfilled with oil and will expel unneeded/unwanted oil and seek a level that IT wants not you. 360s 6 quarts would be pretty normal. 

how exactly did you figure out 2.5 quarts per 10 hours! Fill to 7, fly 4 hours, its at 6 , add a quart, fly 4 hours its at 6 again , add a quart, fly 2 hours,  its 6.5 add a 1/2 quart? 

People on MS are reallly helpful and smart, if you let them they will figure this out, but your going to have a lot of questions from several different people  that will need more exact,  specific answers. 

 

 

I'm liking the questions! I'm no mechanic but I love getting my hands dirt and this is definitely educating me on my new plane! 

In regards to the oil change we would add 7 quarts, the dip stick would read 7 quarts, I would fly the plane home. 30min and the next day when I would check it it would be at 6 (my guess is due to oil filter  and cooler taking up some oil).. next day I would do a 2 hour breakfast run and the fallowing day or next time I go flying it would be between 5 and 5.5 quarts. The case is not leaking. I have no visible drips on the engine nore inside the cowling. Next step will have to be a compression test to see if the rings are any good. I know if I run anything over 6 it's definetly on the belly. 

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To me, that’s 1 qt every 4 hours.  Basically just counting the 2 hour lunch run from 6 to 5.5.  The first part is just putting oil into your filter. Anything over 6 quarts will definitely be on your belly, and if the dipstick isn’t right you may be running 6 1/2 or 7 quarts and not realizing it. 

not great, but not terrible.   Better than Lycoming advertised limit.  Mine is like 1 in 6.5 hrs.  To me, this seems like break in didn’t go right.  Borescope be good.  Compressions be good.

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I have an antenna behind the oil breather.   I clean it then check how dirty it gets.  Not as accurate as a Engine monitor, but not bad for rule of thumb.  I run my A1A between 5 and 6 quarts.   I can tell it needs oil when the oil pressure gauge starts pulsing.

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10 hours ago, asaxet said:

My A1A  has its best burn rate if kept between 4  and 5 qts...    

I have no factual data but It also seems that if I run my RPM at 2400 instead of 2500 for cruise I use less oil, same HP% settings.

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I didnt know the rpms would go that low...   LOL     maybe  I'm stuck on the MAPA article that suggests any thing other than 25/25 is a waste of  Mooney, money and/or Time..     

Good info to know...   Thanks...    i'll have to try it out on mine...   

 

but back to the thread...  if i put more than 5 qts in the sump...  in short order ends up on the belly of my bird...  

 

 

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I did a top end recently and broke it in hard, wide open throttle, 2500 to 2600 rpm, a little off of full rich to keep the cylinders cool and below 2000 agl - it was neat to see that bird fly at the top portion of the yellow arc!! 

Like everyone else with an A1A "over 6 is overboard"  I'm getting 16 + hours before adding, typically less than a quart. 

Unless the ring gap is too wide at this point from a poor break in, I'd check with your mechanic, if there's no other obvious cause for the oil loss I'd  take another swing at breaking in the cylinders - make sure to use break in oil.

 

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On ‎10‎/‎14‎/‎2018 at 10:32 PM, carusoam said:

The purpose of running WOT, max rpm, mixture in, is to keep a wear step from forming in one place that is shy of where the piston rings travel under take off conditions. The max mixture is for additional cooling during the high heat period of break-in...

OT, I know, but I remain skeptical of some of the ideas behind engine break-in.  I mean, how could the piston ring TRAVEL be different under different speeds and power?  I mean, it's not like the crankshaft changes shape or anything.  Likewise, if there's a "step" formed because you require high power/speed to somehow deform the engine components, how would it have anything to do with oil consumption, since we tend to run the engine in cruise at a lower power/speed than the break-in procedures anyway? :blink:

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9 minutes ago, jaylw314 said:

OT, I know, but I remain skeptical of some of the ideas behind engine break-in.  I mean, how could the piston ring TRAVEL be different under different speeds and power?  I mean, it's not like the crankshaft changes shape or anything.  Likewise, if there's a "step" formed because you require high power/speed to somehow deform the engine components, how would it have anything to do with oil consumption, since we tend to run the engine in cruise at a lower power/speed than the break-in procedures anyway? :blink:

No feeling like breaking in a $30,000 purchase by running it as hard as mechanically possible for the first few hours.

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Being only a PP,  I can only speculate...

The relationship of everything in motion is not quite perfectly stable...

there are a few degrees of freedom as the crank turns... there is a bearing that the piston’s connecting rod is riding on... and there is a wrist pin the piston is allowed to rotate around... and there are clearances everywhere...

Between speed and momentum things are going to move differently while running...

I know the break in procedure for my engine specifically mentioned changing rpm every 15 minutes...

An indication that somebody at the engine manufacturer has done this with knowledge and for some reason...

There might be temperatures that make things elongate as well...

Break in flights can be both fun and thrilling... the IO550 is a bit more expensive, it’s prop was brand new, and nothing about it was familiar anymore...

I brought along a MAPA CFII to oversee a couple of hours of operation...

Too many things can be easily omitted while screaming along the deck at full power... we used the length of the Jersey Shore for that...

I also didn’t want to be alone if and when the oil pressure exited the new engine... :)

PP thoughts only, not a mechanic...

Best regards,

-a-

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That is an interesting read, Jay.

They cover many steps prior to actually running the engine live...

My engine already ran in a lab in Alabama (at CMI)... Before being shipped for installation in NJ.

Then a couple of flights in the extended traffic pattern... expecting a possible engine out...

Then the long cross country type flights...

I did like the detail of the article.. it didn’t specifically mention that the air cooled engine is what they were referring to... as that adds a lot of dimensional change compared to water cooled...

They kept it short and used hydro-dynamics without going into the details of the lubrication approximation... :)

So... my engine had about four hours of run time before I ever flew it...

Two hours in the lab, two hours around the pattern flown by my favorite FBO owner/test pilot...

Expecting to see high CHTs at first, followed by the CHTs settling down as the break-in finished up...

It was all done before I got it...

maybe I should go check the hours in the log book on that...

How far would you go if somebody handed you the keys to a plane with 310hp?

Flying around in an IO550 at full throttle can run through a lot of 100LL...

About 27-30gph depending on who does the set-up... and what RPM is being used... enough power it is easy to exceed Vne in a slight descent from 2k’ to one...

The procedure to follow was only a few pages long and was pretty specific of what to get done at each step of the program... No magic.

The only uneasy feeling I got... the warranty period is only a few months?  At the rate I could fly, I barely got the break-in flights completed before the time was running out....

No issues came up, it’s been about six years...

Best regards,

-a-

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