chuck911

So let me get this straight. Your airplane guy breaks in his brand new airplane engine by running it TWO FULL HOURS at redline, as soon as its warmed up? His airplane engine. That he flies with. In the air. Where his life may depend on it. And you STILL don't get that there's no harm in this?

I am really beginning to understand now why Gary says "I don't care!"

speed21

^ Lol. Nice try Chuck. And fwiw Gary is spot on. Science is absolutely key.

Hey just for a bit of internet trivia on aircraft engines...Page 17 points #7 and #8 amongst a few.
http://www.eci.aero/pdf/BreakInInstructions.pdf

Every engine has an optimum running in procedure set down by the maker. This is for a reason. Not every engine is the same even though they all may have pistons liners and rings.

A Porsche engine is not an Aircraft engine, and has its own set of running in procedures. A wise person takes notice of those procedures.

Component design, engine design are all relevant factors and it should not be assumed, precluded, nor preached by anyone the same procedure applies to every engine made on the planet.

It should also not be assumed engines removed for testing are put into new vehicles.

Component design, engine design and the rigorous scientific testing (as Gary has also pointed out) that goes in to the creation of the finished product ultimately determines the best procedure to achieve optimum life and performance, not Mr Olimotoman.



PS. Btw Chuck, out of curiosity, you don't by chance happen to be Motoman?....no offence intended.

chuckbdc

So there you are: you now know to run your engine up to 2700 rpm when you get your car. Specifics from authorities like friends of Internet friends are your friend! Oh and be sure to operate your 991 over its life the way aircraft engines are operated, staying at ~50-60% of rated poser for durability and safety.

pt767

A bit of trivia....Porsche built an aircraft engine for the Mooney in the early/mid 80's. I believe they did 40 or so engines and the program was a total disaster ( in terms of sales/economics). Oh well....stick to making car motors! The break in debate lives on!! Happy new year to all!

jmct

I don't think I follow the logic of this last comment, I believe you may not have understood the post in detail.

In any case, I am ready to move on. I was interested in hearing your view in greater detail in case I could learn something, thank you for providing it.

I hope you enjoy your 911 when you get it.

chuck911

Wow. And I thought jmct was bad enough with his "the appeal to authority is to be applied", no thinking allowed approach.

From your ECI Aero pdf:
Page 1: CAUTION: Some approved oils contain anti‐scuffing additives that should NOT be used during engine break‐in. Always refer to the label to ensure that the oil is correct for your application.

How is this different than Motoman recommending not using synthetics because they are too slippery? (Rhetorical question. I know the answer! Its different because the guy you choose to believe is - in your mind - an AUTHORITY!)

Page 3: Airplane owners, builders of aircraft engines, and component suppliers such as Engine Components International (ECi®) have a mutual interest in engine break‐in. All want the engine to perform and give long and satisfactory service life.

This is patently false. Only the owner has an interest in longevity. Manufacturers of engines and parts have an interest in optimizing profits made from selling engines and parts to owners.

Page 3: Another CAUTION: When an engine fails to give satisfactory service, it is frequently due to: unseated piston rings due to improper break‐in...

Unseated piston rings. First item on the list. Now where have I heard that one before? Nevermind. I'm sure it didn't come from an Authority on the Approved list.

Page 3: We Strongly Recommend These Precautions:
1. Pressure oil the engine before the first start‐up after the engine has been
installed in the airplane.

Anybody remember my question about when does most bearing wear happen? Nobody answered. Probably never even gave it any thought. (There's a pattern here...) The answer: on start-up. Engine's sitting a while can result in loss of oil film. After startup, oil pressure, no bearing wear. ECI is right. And guess where I got my example? Hint: it wasn't from An Authority Figure.

6. NOTE: Do not put Textron Lycoming oil additive P/N LW‐16702 in O‐320H
and O/LO‐360E engines for break‐in. This oil additive will inhibit break‐in so it
should only be added after break‐in has occurred. (See Lycoming S.I. No. 1014M Part II.B)

You should write them a letter complaining how much harm duplicating the advice of non-authorities does to their Authority Status!

Page 5. Typically, most engine overhaul shops run‐in all opposed engines for a period of one to two hours prior to release for installation. However, this run was never intended to be a break‐in run. The objective of the run‐in test is to:
1. Prove that the engine will produce rated power.

OMG! Surely not FULL rated power! Oh... now I get it.... "most engine overhaul shops"! Nevermind what they do. They're not Authoritative. These aren't the droids you're looking for....

NOTE: The following information applies to all types of cylinder bores:
STEEL/CAST IRON ‐ Plain, nitrided, through hardened
CHROME ‐ Porous, silicon carbide impregnated
NICKEL COMPOSITE ‐ CermiNilTM process or Nickel+CarbideTM

Do I really need to say it?

11. Use take‐off power only as long as necessary to get to BEST CLIMB SPEED. Reduce manifold pressure to minimum required for clean in‐flight attitude. Leave propeller in flat pitch for at least 5 minutes after take‐off. For aircraft not equipped with a variable pitch propeller or manifold pressure gauge, reduce power to 75%. Use minimum rate of climb with maximum air speed consistent with terrain.
12. When desired altitude is reached and cylinder head and oil temperatures are satisfactory, aircraft should be operated at 75% power until 20‐30 minutes of flight time have elapsed. The engine should then be operated at various power settings and engine operating parameters observed until at least 45 minutes of flight time have elapsed. All power changes should be made very gradually, especially power reductions.

Again- do I really need to say it? Will it do any good? Is there any reason at this point to think that your Approved Authority blinders and earplugs aren't permanently sutured in?

"KBO"
- Winston Churchill
("Keep Buggering On.")

So now here we are, pretty near the end of the ECI (your Approved Authority) break-in manual. The Approved Authority has told us (and look, he's seriously Approved- not one Music Video link anywhere!) that the most important thing is to SEAT THE PISTONS using FULL RATED POWER as SOON AS THE ENGINE IS WARM, FOR TWO HOURS, then fly it 75% another half an hour, that this advice APPLIES TO ALL KINDS OF CYLINDER LINERS, and oh by the way DON'T DO IT ON LOW FRICTION SYNTHETIC OILS.

Can you ship me a set of those blinders, speed? In case there's a nuclear holocaust. They seem to be the most impenetrable substance ever.

jmct

I don't have anything to add to my preceding posts in relation to this post.

By the way, I sincerely thank speed21, Mike in CA, Gary and others who posted. I benefitted greatly from your comments in a topic that I was very interested in refreshing myself on and appreciate your taking the time to write.

Mike in CA

With pleasure, jmct. Your posts on a contentious subject have been thoughtful and polite and I've benefited from them as well.

simsgw

Not to belabor JMCT's point, but that actually is how we break in the old Lycoming and Continental engines. Because not all engines are the same. Just to touch some highlights,

1. Those engines have the cylinders right out there where they can expand and contract freely. They are cylinders, like a pipe with fins, not cylindrical holes cut into a monolithic block of metal (from which we derive the name 'block' for that biggish lump);
2. Their "red line" is about half of our reduced limit during break-in, so the internal loads on the engine are about a fourth what we tolerate while breaking in the Porsche engine per the manual and about a tenth what our engines experience at our red line;
3. They don't really have a 'red' line because they are power limited in operation. There is no clutch to isolate the engine from the load and that 'high' rpm is just routine cruising rpm, like a 911 dawdling at 70 in seventh;
4. Without elaborate measures mechanics resent, running the prop at a pretty good clip is the way they are kept cool. They have no other coolant circulation and, like formula cars, aircraft engines don't have a fan, except... well that big one out front;
5. We do a thorough inspection every hundred hours of operation and tear them down frequently, doing valve jobs about as often the old timers changed underwear; and
6. They use oil at roughly a pint an hour, give or take.

If that sounds like your engine, Chuck, God bless.

Gary, who still doesn't care, but just saying

simsgw

You're welcome. The only reason I didn't check out of this thread completely was that I felt it might seem I disagreed with you. As if your position and Motuman's nonsense were actually two viable alternatives to considered with a straight face.

Happy new year.

Gary

jmct

Thanks Gary. Happy New Year to you too, hope you have a great '13!

speed21

Sorry guys, (Jmct, Gary, Mike from CA and Chuck) a bit belated but happy new year to you all! And no hard feelings chuck....well not from my end anyway. I did say earlier on that I enjoy the free entertainment side of it, so it wasn't a total dead loss for me.

Ok. Now, to finish up as briefly as possible.

It is logical, and i believe generally accepted by most that engine/vehicle manufacturers will remove the precarious process of the preliminary bedding of rings (note the use of the word preliminary), whilst checking for other defects i.e oil leaks, lack of power and so forth prior to the car leaving the factory. After all, an expensive car like a Porsche, leaving that part to the end user is fraught with danger IYKWIM (..well excepting chuck/motoman who like to mix some drama with the action).

However, just because the manufacturer has removed that particular process doesn't mean it's "all systems go" for the end user to go hell for leather (as Chuck/motoman evidently preach).

Chuck. Accept it or not, the makers preliminary bed in is not the end of the break in story if you want the best of the product, hence Porsches recommended break in procedure. Time/mileage is required to seal the deal properly and running the engine flat out under driving conditions is far different than running it under controlled conditions such as a rolling road or dyno under the hands of experts. Doing what you and motoman are saying is "OK" Is certainly not what i would personally recommend any end user to do. I regularly get to see the net results from your style of recommendations. i.e. warranty claims and the inevitable tussles that follow. Just because the engine can generally take the abuse doesn't mean that there will always be a positive outcome for the end user (sorry to have to tell you that). Yes not every outcome is favourable. Again, Porsche would have done the science to establish the best way to go...not that you will ever take that on board having the genius of motoman as your mentor to rely upon as a support mechanism.

Anyway chuck you have fun with your new car ok....and don't listen to the manufacturer OK. They are up to no good with the conspiracy theories . They just want to sell you more engines and parts or have you go to the opposition next time .

Just remember, it's guys like you and motoman that keep guys like me in business....so, please ensure to keep up the good work . I may need to buy myself a new 991tt soon so don't spare the welly.

Mike in CA

Happy New Year to you too, speed21!