Dawley Aviation PIREP, or: Atlas is BACK

[Jay Honeck]

We were grounded last week, after discovering a cracked exhaust pipe and
rotted muffler baffles during routine maintenance.

Amazingly, we discovered that Dawley Aviation (*the* exhaust repair station
in the Midwest, and the place my A&P recommended) is located in Burlington,
WI -- literally on the road to Racine -- which was where we were headed for
"Xmas II". So, we ripped off the old system and tossed it in the back of
the Subaru with all the luggage and presents.

Four hours after leaving Iowa City, we were at Dawley's VERY impressive
offices. They are clearly a well-established business, with a large, clean
factory floor, and a nice, clean front office area, housing half a dozen
office workers in private offices. It looked more like a bank than any
aviation business I'd ever had the pleasure of seeing before -- quite
different from most of these kinds of places.

Steve, their VERY knowledgeable sales manager, was there to greet us. It
was obvious that he (and the staff) weren't used to having customers drop
stuff off (a steady stream of UPS and FedEx trucks flowed in and out while
we were there), but he took it all in stride and seemed genuinely pleased to
actually SEE someone for a change.

It turned out that Steve had trained with the same CFI as I did, over in
East Troy, Wi, so we were instantly fast friends as we traded "Old Bob"
stories back and forth. He took the cruddy old parts from me, identified
what could be re-used, and said that I could pick the new system up on our
way out of town the next day. It was as easy as that, and we were soon off
to Racine for Xmas with Mary's family.

The next day we swung back into their office, and it was all ready to go.
Dang, they literally replaced EVERYTHING except one flange on both the
triple pipes and the muffler. Everything else is brand-spanking new.

Steve wished Mary and the kids a happy new year, gave each of us a bag of
peanuts (which they apparently always throw in the box -- it's a Dawley
tradition that goes way back to their beginning), and charged us $620. Not
cheap, by any stretch, but still way cheaper than new.

All in all, a very pleasant experience, and a real pleasure to work with a
guy that's so knowledgeable. In answer to questions, Steve went on at great
length about the metallurgy behind the work, and the reasons exhaust systems
fail. (Incidentally, he said that the best thing that EVER happened to
their business was everyone running "lean of peak" and driving their EGTs up
above 1500 degrees. As temperatures approach 1600 degrees, the metal simply
starts to fail, and you end up saving pennies on gas, and blowing dollars on
exhaust systems.)

My A&P put everything back together yesterday, and Atlas is now snug back in
his hangar, with a new exhaust, new oil/filter, new Iridium spark plugs, and
(hopefully) no more oil leak. Now all we need is some flying weather!
--
Jay Honeck
Iowa City, IA
Pathfinder N56993
www.AlexisParkInn.com
"Your Aviation Destination"

[Steve Foley]

Sounds like my A&P too my bag of pranuts :)

"Jay Honeck" > wrote in message
news:ywRtf.692885$xm3.601961@attbi_s21...

> Steve wished Mary and the kids a happy new year, gave each of us a bag of
> peanuts (which they apparently always throw in the box -- it's a Dawley
> tradition that goes way back to their beginning), and charged us $620.
Not
> cheap, by any stretch, but still way cheaper than new.

[Newps]

Jay Honeck wrote:
(Incidentally, he said that the best thing that EVER happened to
> their business was everyone running "lean of peak" and driving their EGTs up
> above 1500 degrees. As temperatures approach 1600 degrees, the metal simply
> starts to fail, and you end up saving pennies on gas, and blowing dollars on
> exhaust systems.)

Done improperly LOP will start to melt exhaust systems. If you're
getting over 1500 EGT then you're not LOP, you're at peak. 75 LOP is
the same temp as 75 ROP.

[Ken Reed]

> (Incidentally, he said that the best thing that EVER happened to
> their business was everyone running "lean of peak" and driving their EGTs up
> above 1500 degrees. As temperatures approach 1600 degrees, the metal simply
> starts to fail, and you end up saving pennies on gas, and blowing dollars on
> exhaust systems.)

1600º is LOR (Lean of Rich) not LOP. 1600º is right at peak, as has been
stated. My engine typically peaks at 1590º. With the BMP (Big Mixture
Pull), I go from ROP through Peak to well LOP in about one second.
Yesterday on my flight I was running at 1490º, or 100º LOP. Now, if I
run it 100º ROP, what will my EGT read ?

BTW - my CHTs were 320º.
---
Ken Reed

[Matt Whiting]

Jay Honeck wrote:

> All in all, a very pleasant experience, and a real pleasure to work with a
> guy that's so knowledgeable. In answer to questions, Steve went on at great
> length about the metallurgy behind the work, and the reasons exhaust systems
> fail. (Incidentally, he said that the best thing that EVER happened to
> their business was everyone running "lean of peak" and driving their EGTs up
> above 1500 degrees. As temperatures approach 1600 degrees, the metal simply
> starts to fail, and you end up saving pennies on gas, and blowing dollars on
> exhaust systems.)

That's funny as this isn't supported by the data the GAMI folks have
taken. It shows the EGTs being pretty much symmetrical about the peak.
So if you go lean of peak far enough you should be able to pretty much
equal the temps seen on the rich side of peak. And CHTs are actually
lower on the lean side so you should be saving your cylinder heads some
grief.

http://www.gami.com/frames.htm

Now if folks are running "at peak", then I see Steve's point, however,
"lean of peak" doesn't have to be problem if done properly.


Matt

[Matt Whiting]

Newps wrote:

>
>
> Jay Honeck wrote:
> (Incidentally, he said that the best thing that EVER happened to
>
>> their business was everyone running "lean of peak" and driving their
>> EGTs up above 1500 degrees. As temperatures approach 1600 degrees,
>> the metal simply starts to fail, and you end up saving pennies on gas,
>> and blowing dollars on exhaust systems.)
>
>
> Done improperly LOP will start to melt exhaust systems. If you're
> getting over 1500 EGT then you're not LOP, you're at peak. 75 LOP is
> the same temp as 75 ROP.

Not the same. It is better as you have the same EGT with much lower CHTs.


Matt

[Matt Barrow]

"Newps" > wrote in message
...
>
>
> Jay Honeck wrote:
> (Incidentally, he said that the best thing that EVER happened to
>> their business was everyone running "lean of peak" and driving their EGTs
>> up above 1500 degrees. As temperatures approach 1600 degrees, the metal
>> simply starts to fail, and you end up saving pennies on gas, and blowing
>> dollars on exhaust systems.)
>
> Done improperly LOP will start to melt exhaust systems. If you're getting
> over 1500 EGT then you're not LOP, you're at peak. 75 LOP is the same
> temp as 75 ROP.

The PROPER way is not so much running ROP or LOP but rather the transition
from full rich to LOP - it has to be done quickly, like 3-4 seconds ("The
Big Pull" as Deakin describes it).

Where jus about everyone gets into trouble is running near peak (i.e., just
a few degrees either side).

Jay is merely parroting the OWT and misinformation that has been running
around out there for _years_.



--
Matt
---------------------
Matthew W. Barrow
Site-Fill Homes, LLC.
Montrose, CO

[Matt Barrow]

"Matt Whiting" > wrote in message
...
> Jay Honeck wrote:
>
>> All in all, a very pleasant experience, and a real pleasure to work with
>> a guy that's so knowledgeable. In answer to questions, Steve went on at
>> great length about the metallurgy behind the work, and the reasons
>> exhaust systems fail. (Incidentally, he said that the best thing that
>> EVER happened to their business was everyone running "lean of peak" and
>> driving their EGTs up above 1500 degrees. As temperatures approach 1600
>> degrees, the metal simply starts to fail, and you end up saving pennies
>> on gas, and blowing dollars on exhaust systems.)
>
> That's funny as this isn't supported by the data the GAMI folks have
> taken. It shows the EGTs being pretty much symmetrical about the peak. So
> if you go lean of peak far enough you should be able to pretty much equal
> the temps seen on the rich side of peak. And CHTs are actually lower on
> the lean side so you should be saving your cylinder heads some grief.
>
> http://www.gami.com/frames.htm
>
> Now if folks are running "at peak", then I see Steve's point, however,
> "lean of peak" doesn't have to be problem if done properly.

Here's the summary:

http://www.avweb.com/news/columns/182084-1.html or, I you prefer, here's the
Printer Friendly version:

http://www.avweb.com/cgi-bin/udt/im.display.printable?client.id=avweb&story.id=182084

Read the graphs and charts.


--
Matt
---------------------
Matthew W. Barrow
Site-Fill Homes, LLC.
Montrose, CO

[Matt Barrow]

"Jay Honeck" > wrote in message
news:ywRtf.692885$xm3.601961@attbi_s21...
> All in all, a very pleasant experience, and a real pleasure to work with a
> guy that's so knowledgeable. In answer to questions, Steve went on at
> great length about the metallurgy behind the work, and the reasons exhaust
> systems fail. (Incidentally, he said that the best thing that EVER
> happened to their business was everyone running "lean of peak" and driving
> their EGTs up above 1500 degrees. As temperatures approach 1600 degrees,
> the metal simply starts to fail, and you end up saving pennies on gas, and
> blowing dollars on exhaust systems.)

Yeah...he's really knowledgeable....on myths and legends.


--
Matt
---------------------
Matthew W. Barrow
Site-Fill Homes, LLC.
Montrose, CO

[Jay Honeck]

>> All in all, a very pleasant experience, and a real pleasure to work with
>> a guy that's so knowledgeable. In answer to questions, Steve went on at
>> great length about the metallurgy behind the work, and the reasons
>> exhaust systems fail. (Incidentally, he said that the best thing that
>> EVER happened to their business was everyone running "lean of peak" and
>> driving their EGTs up above 1500 degrees. As temperatures approach 1600
>> degrees, the metal simply starts to fail, and you end up saving pennies
>> on gas, and blowing dollars on exhaust systems.)
>
> Yeah...he's really knowledgeable....on myths and legends.

Well, I suspect what he *means* is that people are leaning incorrectly in
attempting to run LOP, and/or they are trying to run LOP with carbureted
engines. Everyone is trying to save fuel nowadays, with avgas so high, and
people are simply cooking their exhausts systems in the process.

Steve has no reason to lie (in fact, he has every reason to say just the
opposite!) -- and, as sales manager of the largest exhaust shop in the
world, I suspect he has figured out where his customers are coming from.
--
Jay Honeck
Iowa City, IA
Pathfinder N56993
www.AlexisParkInn.com
"Your Aviation Destination"

[Matt Barrow]

"Jay Honeck" > wrote in message
news:bTZtf.694906$xm3.681484@attbi_s21...
>>> All in all, a very pleasant experience, and a real pleasure to work with
>>> a guy that's so knowledgeable. In answer to questions, Steve went on at
>>> great length about the metallurgy behind the work, and the reasons
>>> exhaust systems fail. (Incidentally, he said that the best thing that
>>> EVER happened to their business was everyone running "lean of peak" and
>>> driving their EGTs up above 1500 degrees. As temperatures approach 1600
>>> degrees, the metal simply starts to fail, and you end up saving pennies
>>> on gas, and blowing dollars on exhaust systems.)
>>
>> Yeah...he's really knowledgeable....on myths and legends.
>
> Well, I suspect what he *means* is that people are leaning incorrectly in
> attempting to run LOP,

Well, you said "running", so it's still open...

OTOH, I wonder if he ever found out how much damage was done using the
techniques that (literally) "everyone" used in the past of running a few
degrees of peak. Remember that such was THE technique for years and years.

The problem is that people do two things wrong in GETTING to LOP; either
chickening out and staying near peak, or they make the transition from ROP
to LOP by taking several minutes while the engine is near peak.

Unless that's what he's talking about (I'm doubtful) I've seen nothing to
indicate he knows what the hell he's talking about.

> and/or they are trying to run LOP with carbureted engines.

LOP with carburated engines is not a problem other than the likely roughness
that would cause kidney problems.


> Everyone is trying to save fuel nowadays, with avgas so high, and people
> are simply cooking their exhausts systems in the process.

And how would that differ from the late 70's?


> Steve has no reason to lie (in fact, he has every reason to say just the
> opposite!) -- and, as sales manager of the largest exhaust shop in the
> world, I suspect he has figured out where his customers are coming from.

Didn't say he lied, I said he doesn't know what he's talking about. There's
a likely disconnect between an exhaust shop and expertise on engine
management. We've seen plenty that indicates the engines shops are just
parroting the myths and legends as well.

[Newps]

Matt Whiting wrote:

>> Done improperly LOP will start to melt exhaust systems. If you're
>> getting over 1500 EGT then you're not LOP, you're at peak. 75 LOP is
>> the same temp as 75 ROP.
>
>
> Not the same.

It is precisely the same. 75 LOP is the same as 75 ROP. We are talking
EGT's not CHT's.


It is better as you have the same EGT with much lower CHTs.

Well yeah.

[Jon Kraus]

Jay,

If you only paid .62 AMU for your exhaust system rebuild then you got a
great deal!! Was this for a complete system or just the muffler and a
couple of pipes? We had to have our exhaust completely rebuilt last
annual (OI-360) from Dawley, but it cost us 1.8 AMU's. That was
replacing everything including one pipe that they couldn't "rebuild" and
we had to buy new from Mooney. The 1.8 AMU's we paid also included the
20% rip-off, er markup that our shop charges for the privilege of
letting them order parts for us. So in reality our system should have
cost 1.5 AMU's if we would have dealt with Dawley directly (which we
will from here on out), so if you go a complete system for .62 AMU then
my hat is off to you for procuring such a good deal!!

Jon Kraus
'79 Mooney 201
4443H @ TYQ

Jay Honeck wrote:
> We were grounded last week, after discovering a cracked exhaust pipe and
> rotted muffler baffles during routine maintenance.
>
> Amazingly, we discovered that Dawley Aviation (*the* exhaust repair station
> in the Midwest, and the place my A&P recommended) is located in Burlington,
> WI -- literally on the road to Racine -- which was where we were headed for
> "Xmas II". So, we ripped off the old system and tossed it in the back of
> the Subaru with all the luggage and presents.
>
> Four hours after leaving Iowa City, we were at Dawley's VERY impressive
> offices. They are clearly a well-established business, with a large, clean
> factory floor, and a nice, clean front office area, housing half a dozen
> office workers in private offices. It looked more like a bank than any
> aviation business I'd ever had the pleasure of seeing before -- quite
> different from most of these kinds of places.
>
> Steve, their VERY knowledgeable sales manager, was there to greet us. It
> was obvious that he (and the staff) weren't used to having customers drop
> stuff off (a steady stream of UPS and FedEx trucks flowed in and out while
> we were there), but he took it all in stride and seemed genuinely pleased to
> actually SEE someone for a change.
>
> It turned out that Steve had trained with the same CFI as I did, over in
> East Troy, Wi, so we were instantly fast friends as we traded "Old Bob"
> stories back and forth. He took the cruddy old parts from me, identified
> what could be re-used, and said that I could pick the new system up on our
> way out of town the next day. It was as easy as that, and we were soon off
> to Racine for Xmas with Mary's family.
>
> The next day we swung back into their office, and it was all ready to go.
> Dang, they literally replaced EVERYTHING except one flange on both the
> triple pipes and the muffler. Everything else is brand-spanking new.
>
> Steve wished Mary and the kids a happy new year, gave each of us a bag of
> peanuts (which they apparently always throw in the box -- it's a Dawley
> tradition that goes way back to their beginning), and charged us $620. Not
> cheap, by any stretch, but still way cheaper than new.
>
> All in all, a very pleasant experience, and a real pleasure to work with a
> guy that's so knowledgeable. In answer to questions, Steve went on at great
> length about the metallurgy behind the work, and the reasons exhaust systems
> fail. (Incidentally, he said that the best thing that EVER happened to
> their business was everyone running "lean of peak" and driving their EGTs up
> above 1500 degrees. As temperatures approach 1600 degrees, the metal simply
> starts to fail, and you end up saving pennies on gas, and blowing dollars on
> exhaust systems.)
>
> My A&P put everything back together yesterday, and Atlas is now snug back in
> his hangar, with a new exhaust, new oil/filter, new Iridium spark plugs, and
> (hopefully) no more oil leak. Now all we need is some flying weather!

[Jay Honeck]

> If you only paid .62 AMU for your exhaust system rebuild then you got a
> great deal!!

Well, I didn't have to pay any shipping expense! :-)

> Was this for a complete system or just the muffler and a couple of pipes?

It was for the three header pipes on the right side of the engine (as facing
forward) that come together into a single pipe, and the muffler/exhaust
pipe. The heat shroud was the only thing saved.

The left side header was still okay. That would have been another $390 or
so.
--
Jay Honeck
Iowa City, IA
Pathfinder N56993
www.AlexisParkInn.com
"Your Aviation Destination"

[A. Smith]

"Matt Barrow" > wrote in message
...
>>
> Jay is merely parroting the OWT and misinformation that has been running
> around out there for _years_.
>
Jay quotes an expert in the field and you accuse him of parroting
misinformation? LOP is good when properly done, but I think the statement
from Dawley says it is NOT being properly done for the most part. The
company I work for overhauls 400+ aircraft engines a year. Our teardown
shop can tell you which ones have been ran LOP and which have not.

Allen

[Matt Barrow]

"A. Smith" > wrote in message
. net...
>
> "Matt Barrow" > wrote in message
> ...
>>>
>> Jay is merely parroting the OWT and misinformation that has been running
>> around out there for _years_.
>>
> Jay quotes an expert in the field and you accuse him of parroting
> misinformation?

And expert on...what?

> LOP is good when properly done, but I think the statement from Dawley says
> it is NOT being properly done for the most part. The company I work for
> overhauls 400+ aircraft engines a year. Our teardown shop can tell you
> which ones have been ran LOP and which have not.

Really? How?

[A. Smith]

"Matt Barrow" > wrote in message
...
> "A. Smith" > wrote in message
> . net...
>>
>> "Matt Barrow" > wrote in message
>> ...
>>>>
>>> Jay is merely parroting the OWT and misinformation that has been running
>>> around out there for _years_.
>>>
>> Jay quotes an expert in the field and you accuse him of parroting
>> misinformation?
>
> And expert on...what?

An expert on repairing aircraft exhaust. Isn't that what Dawley does?
>
>> LOP is good when properly done, but I think the statement from Dawley
>> says it is NOT being properly done for the most part. The company I work
>> for overhauls 400+ aircraft engines a year. Our teardown shop can tell
>> you which ones have been ran LOP and which have not.
>
> Really? How?

I suggest that if you are really interested in this you get with Lycoming or
TCM and see what they suggest for your engine. There are only a handful of
engines that were designed to be ran LOP.

[Matt Whiting]

A. Smith wrote:
> "Matt Barrow" > wrote in message
> ...
>
>>Jay is merely parroting the OWT and misinformation that has been running
>>around out there for _years_.
>>
>
> Jay quotes an expert in the field and you accuse him of parroting
> misinformation? LOP is good when properly done, but I think the statement
> from Dawley says it is NOT being properly done for the most part. The
> company I work for overhauls 400+ aircraft engines a year. Our teardown
> shop can tell you which ones have been ran LOP and which have not.

I think the point is that it is the temperatue seen by the exhaust pipe
that matters, not whether it is LOP or ROP. And the temps mentioned by
Mr. Dawley sound more like runnint at peak, rather than either side.
People seem to automatically blame running on the lead side and that
simply isn't supported by the data. It is an old wives tale pure and
simple.


Matt

[Matt Whiting]

A. Smith wrote:

> "Matt Barrow" > wrote in message
> ...
>
>>"A. Smith" > wrote in message
. net...
>>
>>>"Matt Barrow" > wrote in message
...
>>>
>>>>Jay is merely parroting the OWT and misinformation that has been running
>>>>around out there for _years_.
>>>>
>>>
>>>Jay quotes an expert in the field and you accuse him of parroting
>>>misinformation?
>>
>>And expert on...what?
>
>
> An expert on repairing aircraft exhaust. Isn't that what Dawley does?
>
>>>LOP is good when properly done, but I think the statement from Dawley
>>>says it is NOT being properly done for the most part. The company I work
>>>for overhauls 400+ aircraft engines a year. Our teardown shop can tell
>>>you which ones have been ran LOP and which have not.
>>
>>Really? How?
>
>
> I suggest that if you are really interested in this you get with Lycoming or
> TCM and see what they suggest for your engine. There are only a handful of
> engines that were designed to be ran LOP.

How do you design an engine to run LOP?


Matt

[A. Smith]

"Matt Whiting" > wrote in message
...
>
> How do you design an engine to run LOP?
>
>
> Matt

Compression ratio, cumbustion chamber shape, valve placement, valve
material, crankshaft counterweight design...............................

[A. Smith]

"Matt Whiting" > wrote in message
...
> A. Smith wrote:
>> "Matt Barrow" > wrote in message
>> ...
>>
>>>Jay is merely parroting the OWT and misinformation that has been running
>>>around out there for _years_.
>>>
>>
>> Jay quotes an expert in the field and you accuse him of parroting
>> misinformation? LOP is good when properly done, but I think the
>> statement from Dawley says it is NOT being properly done for the most
>> part. The company I work for overhauls 400+ aircraft engines a year.
>> Our teardown shop can tell you which ones have been ran LOP and which
>> have not.
>
> I think the point is that it is the temperatue seen by the exhaust pipe
> that matters, not whether it is LOP or ROP. And the temps mentioned by
> Mr. Dawley sound more like runnint at peak, rather than either side.
> People seem to automatically blame running on the lead side and that
> simply isn't supported by the data. It is an old wives tale pure and
> simple.
>
>
> Matt

Which is my point, people think they know how to run LOP but actually are
running at peak, causing damage. The guy at Dawley didn't say running LOP
did the damage, just that when the LOP operation began being pushed is when
the damage started showing up.

Allen

[Matt Whiting]

A. Smith wrote:
> "Matt Whiting" > wrote in message
> ...
>
>>How do you design an engine to run LOP?
>>
>>
>>Matt
>
>
> Compression ratio, cumbustion chamber shape, valve placement, valve
> material, crankshaft counterweight design...............................

Example?

Matt

[john smith]

> >>How do you design an engine to run LOP?

> > Compression ratio, cumbustion chamber shape, valve placement, valve
> > material, crankshaft counterweight design...............................

> Example?

The original Continental in the original Malibu.

[Matt Whiting]

john smith wrote:
>>>>How do you design an engine to run LOP?
>
>
>>>Compression ratio, cumbustion chamber shape, valve placement, valve
>>>material, crankshaft counterweight design...............................
>
>
>>Example?
>
>
> The original Continental in the original Malibu.

I've seen a claim to this effect on Avweb, but haven't seen anything
from TCM. Do you have any data from them that claims this engine was
designed differently for LOP operation? I'd like to see more details.


Matt

[Matt Barrow]

"Matt Whiting" > wrote in message
...
> A. Smith wrote:
>>>
>>>Really? How?
>>
>>
>> I suggest that if you are really interested in this you get with Lycoming
>> or TCM and see what they suggest for your engine. There are only a
>> handful of engines that were designed to be ran LOP.
>
> How do you design an engine to run LOP?
>

So much for "expertise".


--
Matt
---------------------
Matthew W. Barrow
Site-Fill Homes, LLC.
Montrose, CO

[Matt Barrow]

"john smith" > wrote in message
...
>> >>How do you design an engine to run LOP?
>
>> > Compression ratio, cumbustion chamber shape, valve placement, valve
>> > material, crankshaft counterweight
>> > design...............................
>
>> Example?
>
> The original Continental in the original Malibu.

Was configured to run LOP, not designed for it.

[Matt Barrow]

"A. Smith" > wrote in message
om...
>
> "Matt Whiting" > wrote in message
> ...
>>
>> I think the point is that it is the temperatue seen by the exhaust pipe
>> that matters, not whether it is LOP or ROP. And the temps mentioned by
>> Mr. Dawley sound more like runnint at peak, rather than either side.
>> People seem to automatically blame running on the lead side and that
>> simply isn't supported by the data. It is an old wives tale pure and
>> simple.
>>
>>
>> Matt
>
> Which is my point, people think they know how to run LOP but actually are
> running at peak, causing damage. The guy at Dawley didn't say running LOP
> did the damage, just that when the LOP operation began being pushed is
> when the damage started showing up.

That's a nice stretch of the original quote....and I've heard of mechanics
finding all sorts of damages from running LOP when the engine was not run
LOP at all. It's been a favorite excuse for years.

Remember that for YEARS, the favorite leaning technique was to lean to peak,
then enrich slightly (which would put temps at about 50ROP, the "Red Box"

Red Box = No Fly Zone
At and below about 60% power, there is no red box.
At about 65% power or so, 100ºF ROP to Peak.
At about 70%, 125ºF ROP to 25ºF LOP.
At about 75%, 180ºF ROP to 40ºF LOP.
At about 80%, 200ºF ROP to 60ºF LOP


Before you stick your foot into it even deeper, read this and pay particular
attention to the charts and graphs:
http://www.avweb.com/news/columns/182084-1.html

Don't worry about the text so much as the graphical data.

[John Clonts]

> 1600º is LOR (Lean of Rich) not LOP. 1600º is right at peak, as has been

That's funny!

[Allen]

"Matt Barrow" > wrote in message
...
>
> "A. Smith" > wrote in message
> om...
>>
>> "Matt Whiting" > wrote in message
>> ...
>>>
>>> I think the point is that it is the temperatue seen by the exhaust pipe
>>> that matters, not whether it is LOP or ROP. And the temps mentioned by
>>> Mr. Dawley sound more like runnint at peak, rather than either side.
>>> People seem to automatically blame running on the lead side and that
>>> simply isn't supported by the data. It is an old wives tale pure and
>>> simple.
>>>
>>>
>>> Matt
>>
>> Which is my point, people think they know how to run LOP but actually are
>> running at peak, causing damage. The guy at Dawley didn't say running
>> LOP did the damage, just that when the LOP operation began being pushed
>> is when the damage started showing up.
>
> That's a nice stretch of the original quote....and I've heard of mechanics
> finding all sorts of damages from running LOP when the engine was not run
> LOP at all. It's been a favorite excuse for years.
>
> Remember that for YEARS, the favorite leaning technique was to lean to
> peak, then enrich slightly (which would put temps at about 50ROP, the "Red
> Box"
>
> Red Box = No Fly Zone
> At and below about 60% power, there is no red box.
> At about 65% power or so, 100ºF ROP to Peak.
> At about 70%, 125ºF ROP to 25ºF LOP.
> At about 75%, 180ºF ROP to 40ºF LOP.
> At about 80%, 200ºF ROP to 60ºF LOP
>
Which orifice did you pull these numbers from?

> Before you stick your foot into it even deeper, read this and pay
> particular attention to the charts and graphs:
> http://www.avweb.com/news/columns/182084-1.html
>
> Don't worry about the text so much as the graphical data.
>

Do you even bother to read what you cite? Look at the gauges in the
aircraft panel in the article you quote. The LH EGT shows 1595 degrees and
the RH shows 1585 degrees. Both seem pretty near the 1600 degrees that
softens stainless. Why do they use these particular power settings? To
manipulate the data in their favor.

[Peter R.]

Matt Barrow > wrote:

> it has to be done quickly, like 3-4 seconds ("The
> Big Pull" as Deakin describes it).

When flying with an engine equipped with their turbo-normalization system,
Tornado Alley recommends the pull from full rich to LOP take about 6
seconds.


--
Peter

[Matt Barrow]

"Peter R." > wrote in message
...
> Matt Barrow > wrote:
>
>> it has to be done quickly, like 3-4 seconds ("The
>> Big Pull" as Deakin describes it).
>
> When flying with an engine equipped with their turbo-normalization system,
> Tornado Alley recommends the pull from full rich to LOP take about 6
> seconds.

NO MORE THAN six seconds.


--
Matt
---------------------
Matthew W. Barrow
Site-Fill Homes, LLC.
Montrose, CO

[Matt Barrow]

"Allen" > wrote in message
...
>
> "Matt Barrow" > wrote in message
> ...
>>
>> "A. Smith" > wrote in message
>> om...
>>>
>>> "Matt Whiting" > wrote in message
>>> ...
>>>>
>>>> I think the point is that it is the temperatue seen by the exhaust pipe
>>>> that matters, not whether it is LOP or ROP. And the temps mentioned by
>>>> Mr. Dawley sound more like runnint at peak, rather than either side.
>>>> People seem to automatically blame running on the lead side and that
>>>> simply isn't supported by the data. It is an old wives tale pure and
>>>> simple.
>>>>
>>>>
>>>> Matt
>>>
>>> Which is my point, people think they know how to run LOP but actually
>>> are running at peak, causing damage. The guy at Dawley didn't say
>>> running LOP did the damage, just that when the LOP operation began being
>>> pushed is when the damage started showing up.
>>
>> That's a nice stretch of the original quote....and I've heard of
>> mechanics finding all sorts of damages from running LOP when the engine
>> was not run LOP at all. It's been a favorite excuse for years.
>>
>> Remember that for YEARS, the favorite leaning technique was to lean to
>> peak, then enrich slightly (which would put temps at about 50ROP, the
>> "Red Box"
>>
>> Red Box = No Fly Zone
>> At and below about 60% power, there is no red box.
>> At about 65% power or so, 100ºF ROP to Peak.
>> At about 70%, 125ºF ROP to 25ºF LOP.
>> At about 75%, 180ºF ROP to 40ºF LOP.
>> At about 80%, 200ºF ROP to 60ºF LOP
>>
> Which orifice did you pull these numbers from?

Not that anal cavity in your head, that's for sure.
>
>> Before you stick your foot into it even deeper, read this and pay
>> particular attention to the charts and graphs:
>> http://www.avweb.com/news/columns/182084-1.html
>>
>> Don't worry about the text so much as the graphical data.
>>
>
> Do you even bother to read what you cite? Look at the gauges in the
> aircraft panel in the article you quote. The LH EGT shows 1595 degrees
> and the RH shows 1585 degrees. Both seem pretty near the 1600 degrees
> that softens stainless. Why do they use these particular power settings?
> To manipulate the data in their favor.
Did you even read (comprehend) the material?

Get your head out of your orifice and quit pretending to comprehend that
data.

If there's a reason people can't handle LOP leaning, it's because they have
a similar level of competence as Allen.

[Montblack]

("Matt Barrow" wrote)
> Did you even read (comprehend) the material?
>
> Get your head out of your orifice and quit pretending to comprehend that
> data.


Can you comprehend why people trim their posts?

The orifice thing, too :-)


Montblack

[Jonathan Goodish]

In article >,
Jon Kraus > wrote:
> If you only paid .62 AMU for your exhaust system rebuild then you got a
> great deal!! Was this for a complete system or just the muffler and a
> couple of pipes? We had to have our exhaust completely rebuilt last
> annual (OI-360) from Dawley, but it cost us 1.8 AMU's. That was
> replacing everything including one pipe that they couldn't "rebuild" and
> we had to buy new from Mooney. The 1.8 AMU's we paid also included the
> 20% rip-off, er markup that our shop charges for the privilege of
> letting them order parts for us. So in reality our system should have
> cost 1.5 AMU's if we would have dealt with Dawley directly (which we
> will from here on out), so if you go a complete system for .62 AMU then
> my hat is off to you for procuring such a good deal!!

I had my exhaust system replaced by Dawley a couple months ago. It was
around $1.5k including installation. All four standpipes were
overhauled (to replace ends) and two new mufflers were provided. The
shop who did the work extracted a premium also, but shipping was about
$200 for 2-day both ways.

However, I'm glad that I had the work done. Muffler was still intact,
though worn, but the standpipes were leaking badly at the slip joints
with the muffler. Dawley did an outstanding job at reworking the pipes,
and they did the work same-day.



JKG