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1. 10:11 AM - Re: (flylightning)
2. 01:33 PM - Excellent treatise on LOP operation (Thom Riddle)
3. 02:59 PM - Re: Excellent treatise on LOP operation (BobsV35B@aol.com)
4. 04:30 PM - Re: Excellent treatise on LOP operation (Thom Riddle)
5. 05:18 PM - Re: Re: Excellent treatise on LOP operation (BobsV35B@aol.com)
Message 1
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Bob,
I have always done it that way. Fully depressed and than 360, never have
bothered to re-check after so probably ok.
Nick
_____
From: owner-jabiruengine-list-server@matronics.com
[mailto:owner-jabiruengine-list-server@matronics.com] On Behalf Of Robert
Rivard
Sent: Tuesday, April 13, 2010 4:07 PM
Subject:
Any advice on setting the valve clearance on a 2200 solid lifter engine. I
followed the manual by rotating the prop 360 degrees from when the valve was
fully depressed and set at .010.I did all the valves following this
proceedure. Then I rechecked by checking the clearance by rotating engine
till one valve was depressed then checked the other. The valve which was set
at .010 now has a clearance of .012 in this position. This was true of all
the valves when I checked using the second method..Which is correct?
BOB
Message 2
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| Subject: | Excellent treatise on LOP operation |
With all of the recent discussions on operating Lean of Peak and EGT variation
among cylinders I thought it would be useful to post a link to an excellent treatise
on the subject, including the fundamentals of 4-stroke engine operation.
Those who think they really understand 4-stroke engines well, may be tempted
to skip the first part. I suggest you not skip this part no matter how well versed
you are on the subject.
http://www.buy-ei.com/Manuals/The%20Pilots%20Manual%20(by%20EI).pdf
If you have already seen and read this, great. If not have fun reading this long
but informative article and learning what we all should know to operate our
engines properly for long life and efficiency.
Thom Riddle
Buffalo, NY
http://sites.google.com/site/riddletr/a&pmechanix
--------
Thom Riddle
Buffalo, NY
Kolb Slingshot SS-021
Jabiru 2200A #1574
Tennessee Prop 64x32
An ounce of action is worth a ton of theory.
- Friedrich Engels
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=295020#295020
Message 3
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| Subject: | Re: Excellent treatise on LOP operation |
Good Afternoon Thom,
E.I. makes great product and I applaud their effort to spend time and money
trying to write something that will help us all operate our engines safer
and more efficiently.
Unfortunately, they have taken the bait and made a number of very wrong
interpretations of fact. It would take a full fledged engine course to refute
or reevaluate each statement in their lengthy narrative, but it is a very
poor document.
There is no doubt that when an engine has very poor fuel distribution
between cylinders it is going to be difficult to operate well. The E.I products
do a fine job of telling the operator just how good that distribution
really is.
E.I. spends a lot of time presenting excellent information and then asks
engine rebuilders how an engine should be operated. That is a completely
irrational method of evaluating the problem.
I agree that most engine shops see a lot of heat damaged engines. If they
assume the engines are being damaged because the pilot leaned when he should
not have, they are making an unwarranted accusation.
My personal opinion is that a very high percentage of heat damaged engines
are seen because the engine is not rich enough during takeoff and other
high power operations, but that is rarely because the pilot has intentionally
leaned the engine. It is more commonly caused by the engine distribution
being so bad that some cylinders ARE operating way too lean or that the fuel
system is not providing enough fuel to avoid detonation at the high power
settings. Both Continental and Lycoming tell us that you can run at any
mixture setting you want when operating at lower power settings. E.I. correctly
states that Continental sets that point at 65 per cent power and Lycoming
calls for 75 percent.
EI made a gross error when they said that the engine runs it's hottest and
that the valves run their hottest at peak EGT.
That is just not true!
The engine runs it's very hottest close to best power. Best power is when
you are getting as much power as can be gotten from the amount of air the
engine is sucking in. That is close to the hottest place it can run. The
actual hottest point is just about 40 degrees Fahrenheit on the lean side of
best power, but still about 60 degrees rich of peak EGT.
Once again, completely discussing this whole subject is far beyond what I
should be doing here, but I am really saddened that a Company such as E.I.
puts out such drivel.
I have been very pleased with every product I have purchased from E.I and
their service has been excellent.
They should stick to what they know something about and not present a
false interpretation of what has been taught by Taylor and others. LOP
operations can make an engine last a LOT longer. The airlines ran their big round
engines leaner than Peak EGT for most of the round engines lives. Many of us
have several thousand hours behind various big bore engines being operated
on the lean side of best power. It works!
Engines last longer and burn less fuel at equivalent cruise speeds. Best
BSFC is a good thing and it was hardly mentioned by E.I. Very Sad.
Happy Skies,
Old Bob
AKA
Bob Siegfried
Downers Grove, Illinois.
Lean side operator for almost sixty years.
In a message dated 4/20/2010 3:33:48 P.M. Central Daylight Time,
riddletr@gmail.com writes:
http://www.buy-ei.com/Manuals/The%20Pilots%20Manual%20(by%20EI).pdf
Message 4
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| Subject: | Re: Excellent treatise on LOP operation |
Old Bob,
I appreciate your feedback on the E.I. document. I did not catch their error stating
the the hottest an engine gets is at/near peak EGT because I already knew
that it is much closer to peak power than peak EGT. Common sense will tell you
that, and because it is common sense I choose to believe that the statement
as you found it was probably an accidental error on their part. Why the editors
did not catch that is another question. However, they did not dispute the
fact that LOP operation, the primary thesis of the paper, is far better for longevity
than near highest power.
I also agree that surveying rebuild shops is not the best way to get the information
that they stated they were looking for, but doing that did satisfy another
(unstated) purpose which is that ignorant pilots are the cause of most engine
longevity problems and therefore every pilot should buy their product. This
document, if read and understood by all pilots (errors and all) would go a long
way toward reducing the number of pilot induced premature engine overhauls.
With the exception of some errors, either out of ignorance or misinterpretation,
or willful misrepresentation (I doubt this), I maintain that the document has
some value. Of course, you are free to disagree vehemently with me.
As you noted, different engine manufacturers specify different % power over which
LOP is not good for the engine. Jabiru apparently uses 70% power since the
jet needle they designed for the Bing 94 begins getting much richer at approximately
that power setting, assuming the prop used is within the rpm specs. they
recommend.
--------
Thom Riddle
Buffalo, NY
Kolb Slingshot SS-021
Jabiru 2200A #1574
Tennessee Prop 64x32
An ounce of action is worth a ton of theory.
- Friedrich Engels
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=295034#295034
Message 5
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| Subject: | Re: Excellent treatise on LOP operation |
Good Evening Thom,
Not only will I not disagree vehemently, I will agree completely.<G>
I think it is great that they bothered to publish what they did, I just
wish it contained more balanced recommendations. There is a lot of good
information there for those who wish to study it carefully.
I really like E.I and regularly recommend as well as use their products.
Until we get electronic fuel flow and ignition systems that can handle it
all, it is up to we aviators to understand what is happening.
The best short course on engine management that I am aware of is the one
presented by some associates of Tornado Alley Turbo. (The folks who make the
factory installed turbo for the Cirrus) They teach a two and a half day
weekend course that is outstanding. The same course is available in a self
study mode, but attending the course with a bunch of eager aviators is a lot
more fun!
As a very minor point, if we can get enough turbo charging, it is possible
to run lean of peak safely at powers of 90 percent or more!
As Always, It All Depends!
Happy Skies,
Old Bob
In a message dated 4/20/2010 6:30:33 P.M. Central Daylight Time,
riddletr@gmail.com writes:
--> JabiruEngine-List message posted by: "Thom Riddle"
<riddletr@gmail.com>
Old Bob,
I appreciate your feedback on the E.I. document. I did not catch their
error stating the the hottest an engine gets is at/near peak EGT because I
already knew that it is much closer to peak power than peak EGT. Common sense
will tell you that, and because it is common sense I choose to believe that
the statement as you found it was probably an accidental error on their
part. Why the editors did not catch that is another question. However, they
did not dispute the fact that LOP operation, the primary thesis of the
paper, is far better for longevity than near highest power.
I also agree that surveying rebuild shops is not the best way to get the
information that they stated they were looking for, but doing that did
satisfy another (unstated) purpose which is that ignorant pilots are the cause
of most engine longevity problems and therefore every pilot should buy their
product. This document, if read and understood by all pilots (errors and
all) would go a long way toward reducing the number of pilot induced
premature engine overhauls.
With the exception of some errors, either out of ignorance or
misinterpretation, or willful misrepresentation (I doubt this), I maintain that
the
document has some value. Of course, you are free to disagree vehemently with
me.
As you noted, different engine manufacturers specify different % power
over which LOP is not good for the engine. Jabiru apparently uses 70% power
since the jet needle they designed for the Bing 94 begins getting much richer
at approximately that power setting, assuming the prop used is within the
rpm specs. they recommend.
--------
Thom Riddle
Buffalo, NY
Kolb Slingshot SS-021
Jabiru 2200A #1574
Tennessee Prop 64x32
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