Turbo engine maintenance

If it has a recording engine analyzer installed (many a/c of that class,
performance do), ask for a memory dump of whatever is stored in its memory
and watch that memory dump take place, if possible. That could tell a lot
about how it's been operated.

DL

wrote in message
...
snip.

Play dumb and interested. At a minimum, ask about %power at
cruise/fuel flow/ITT-after all, you want to keep operating it the same
way it's been operated ; ) Ask him/her to take you for an extended
test hop to "see how it flies". Pay close attention to his/her
climb/cruise profile & power settings and the indicated temps. Ask
about performance and altitude & have him/her show you. Check the oil
consumption after 30 minutes in cruise, minimum. Paying for a little
fuel can net you a lot of information.

TC

"DL" wrote in message
news
If it has a recording engine analyzer installed (many a/c of that class,
performance do), ask for a memory dump of whatever is stored in its memory
and watch that memory dump take place, if possible. That could tell a lot
about how it's been operated.


I know the JDIs have that capability, does the EI analyzers have that option
as well? (I think that's what this one has)

"jmk" wrote in message
ups.com...
One thing to do is check the turbocharger. Climb to altitude (up
around 18K or so) and pull the RPM back. See how much MP you can get.
[Merlyn used to have a nice chart - might be on their web site.] A
worn turbocharger won't give rated boost up in the thin air (but almost
any piece of scrap metal will give lots of boost down low).

Check the turbocharger housing very carefully for cracks. Case cracks
are not uncommon. Induction leaks are also a pain (usually trivial to
fix, but can be hard (timeconsuming) to find).

OTOH, there is no reason why a well maintained system shouldn't make it
to TBO or close to it (new TCM cylinders being the exception - they
tend to last 400-700 hours, period!). I fly a turbo Arrow and really
enjoy the "high flight." I won't say I wouldn't buy a non-turbo
aircraft, but it would be hard to give up the turbo after having one.


Is there an altitude, where you have to start using more and more fuel to
keep the engine cool to a point where it's not worth the extra few knots you
might get by flying higher?

If you are talking about the Turbo Lance with an intercooler this isn't a
problem

Mike
MU-2

"John Doe" wrote in message
news:erE0f.500$L24.30@lakeread01...

"jmk" wrote in message
ups.com...
One thing to do is check the turbocharger. Climb to altitude (up
around 18K or so) and pull the RPM back. See how much MP you can get.
[Merlyn used to have a nice chart - might be on their web site.] A
worn turbocharger won't give rated boost up in the thin air (but almost
any piece of scrap metal will give lots of boost down low).

Check the turbocharger housing very carefully for cracks. Case cracks
are not uncommon. Induction leaks are also a pain (usually trivial to
fix, but can be hard (timeconsuming) to find).

OTOH, there is no reason why a well maintained system shouldn't make it
to TBO or close to it (new TCM cylinders being the exception - they
tend to last 400-700 hours, period!). I fly a turbo Arrow and really
enjoy the "high flight." I won't say I wouldn't buy a non-turbo
aircraft, but it would be hard to give up the turbo after having one.


Is there an altitude, where you have to start using more and more fuel to
keep the engine cool to a point where it's not worth the extra few knots
you
might get by flying higher?

"Mike Rapoport" wrote in message
ink.net...
If you are talking about the Turbo Lance with an intercooler this isn't a
problem


No intercooler. From what people are saying the company that added the
intercooler has gone out of business.

"John Doe" wrote in message
news:erE0f.500$L24.30@lakeread01...

"jmk" wrote in message
OTOH, there is no reason why a well maintained system shouldn't make it
to TBO or close to it (new TCM cylinders being the exception - they
tend to last 400-700 hours, period!). I fly a turbo Arrow and really
enjoy the "high flight." I won't say I wouldn't buy a non-turbo
aircraft, but it would be hard to give up the turbo after having one.


Is there an altitude, where you have to start using more and more fuel to
keep the engine cool to a point where it's not worth the extra few knots
you
might get by flying higher?

If you want cooler, use lean-of-peak; lose a few knots, but gain
significantly less fuel and lower TIT/CHT temps.


--
Matt

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

On Wed, 5 Oct 2005 07:27:53 -0700, "Matt Barrow"
wrote:


If you want cooler, use lean-of-peak; lose a few knots, but gain
significantly less fuel and lower TIT/CHT temps.

You might want to contact the LOP/GAMI guy and ask him first. Based on
personal experience, turbo-supercharged TIO-540's have detonation
issues during certain operating regimes. Am thinking the GAMI guy saw
the same issues during testing.

TC

wrote in message
...
On Wed, 5 Oct 2005 07:27:53 -0700, "Matt Barrow"
wrote:


If you want cooler, use lean-of-peak; lose a few knots, but gain
significantly less fuel and lower TIT/CHT temps.

You might want to contact the LOP/GAMI guy and ask him first. Based on
personal experience, turbo-supercharged TIO-540's have detonation
issues during certain operating regimes. Am thinking the GAMI guy saw
the same issues during testing.


Who is the "GAMI guy"? Not Deakin?

http://www.avweb.com/news/columns/182132-1.html


--
Matt

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

On Wed, 5 Oct 2005 19:28:50 -0700, "Matt Barrow"
wrote:

Who is the "GAMI guy"? Not Deakin?

http://www.avweb.com/news/columns/182132-1.html

You'll have to forgive my language, but somehow if I tell an owner
something out on the shop floor, or in the 'groups based on my
personal experiences (and experiences of other "unknown" professionals
in the industry) it's hearsay and/or an OWT, but if it gets published
on Avweb, it's freakin' stone tablets handed down from the heavens.

Do me a real big favor and don't ask my professional opinion of "teh
$avvey aviaytor".

I am not disputing the advantages to PROPER LOP cruise operation-on
engines proven to operate LOP-for example, the TCM-powered Malibu was
specifically designed to operate LOP. BUT-if you do not know EXACTLY
what you are doing running a turbo-supercharged GA engine LOP you can
DESTROY your engine. If you don't want to take my word for it, re-read
the article at the link you provided.

TC

BTW the "GAMI guy" is:

George Braly-Chief Engineer


From the article you referenced:

George Braly writes:

"The truth of the matter is, if one does a very, very careful
analysis of all of the Service Difficulty Reports, all of the NTSB
accident reports, and sorts through the data, one comes to the
conclusion that almost all of the detonation that is experienced by
pilots is a result of the following:

1. Fuel quality issues;

2. Magneto and harness cross-firing, or improper magneto
timing;

"There are some reports of detonation that were probably
mis-classified as pre-ignition events due to damaged spark plugs or
heli-coil problems in the cylinder.

"And, last, yes, there are some, a few, cases of detonation that
are "for real" and were caused by very misinformed engine operating
techniques by the pilot. If you get in a pressurized Cessna P-210 and
decide to lean the engine in the mountains for your short field
takeoff, because that is the way you used to do it when you had your
normally aspirated C-210, then you can destroy the engine with pure
detonation by the time you turn cross wind in the traffic pattern. It
will absolutely ruin your day.

"However, in general, detonation is a very rare event and is
usually caused by fuel or ignition problems."

wrote in message
...
On Wed, 5 Oct 2005 19:28:50 -0700, "Matt Barrow"
wrote:

Who is the "GAMI guy"? Not Deakin?

http://www.avweb.com/news/columns/182132-1.html

You'll have to forgive my language, but somehow if I tell an owner
something out on the shop floor, or in the 'groups based on my
personal experiences (and experiences of other "unknown" professionals
in the industry) it's hearsay and/or an OWT, but if it gets published
on Avweb, it's freakin' stone tablets handed down from the heavens.

And many people accept OWT with NO substantiation. Take it on "faith", ya
know. How much proof do youoffer when you tell someone something on the shop
floor? How many people have never heard one word of substantiation for doing
theings the way they did other than from the logical fallacy of Argument
From Authority?


Do me a real big favor and don't ask my professional opinion of "teh
$avvey aviaytor".

I won't ask you opinion on spelling and grammar, either! ! :~)

I am not disputing the advantages to PROPER LOP cruise operation-on
engines proven to operate LOP-for example, the TCM-powered Malibu was
specifically designed to operate LOP. BUT-if you do not know EXACTLY
what you are doing running a turbo-supercharged GA engine LOP you can
DESTROY your engine. If you don't want to take my word for it, re-read
the article at the link you provided.

You can destroy your engine running ROP, too. You can ruin it using numerous
techniques IF YOU DON'T KNOW WHAT YOU'RE DOING.


TC

BTW the "GAMI guy" is:

George Braly-Chief Engineer


From the article you referenced:

George Braly writes:

"The truth of the matter is, if one does a very, very careful
analysis of all of the Service Difficulty Reports, all of the NTSB
accident reports, and sorts through the data, one comes to the
conclusion that almost all of the detonation that is experienced by
pilots is a result of the following:

1. Fuel quality issues;

2. Magneto and harness cross-firing, or improper magneto
timing;

"There are some reports of detonation that were probably
mis-classified as pre-ignition events due to damaged spark plugs or
heli-coil problems in the cylinder.

"And, last, yes, there are some, a few, cases of detonation that
are "for real" and were caused by very misinformed engine operating
techniques by the pilot. If you get in a pressurized Cessna P-210 and
decide to lean the engine in the mountains for your short field
takeoff, because that is the way you used to do it when you had your
normally aspirated C-210, then you can destroy the engine with pure
detonation by the time you turn cross wind in the traffic pattern. It
will absolutely ruin your day.

"However, in general, detonation is a very rare event and is
usually caused by fuel or ignition problems."

Yes...so?

Matt B.

(Five years and 1400 hours LOP in a TNIO-550 without a burp).