Would you by this engine?

I've been shopping for a plane for a while. I'm hoping I found the
one but the engine has given me pause. The engine is 17-years old.
It has ~700 hours on it. The average per year is only 49hr/year. Two
years during that 17, the plane did not fly and I'm guessing it was
not pickled. The latest it sat was in 2000. During the last 6 years,
the plane has mostly flown some 32hrs/year on average. The engine is
a Ly IO-360-A1A. Compression on the engine is 74, 76, 74, 76. The
owner refuses to negotiate on the basis of these concerns and leaves
me nothing to mitigate some of the potential risk.

I spoke with a local mechanic today and his opinion is that it should
give pause but the engine may be fine and was seemingly encouraged by
the compression numbers. He recommends an oil analysis. His opinion
is the biggest potential unseen danger stems from the cam and an oil
analysis would address this concern one way or the other.

Comments? Would you consider such a deal? The mechanic's advice seem
sound?


Greg

It's a Lycoming, compression is always good. You need to check the cam.
Lyc's lose their cams without use.

Greg Copeland wrote:

I've been shopping for a plane for a while. I'm hoping I found the
one but the engine has given me pause. The engine is 17-years old.
It has ~700 hours on it. The average per year is only 49hr/year. Two
years during that 17, the plane did not fly and I'm guessing it was
not pickled. The latest it sat was in 2000. During the last 6 years,
the plane has mostly flown some 32hrs/year on average. The engine is
a Ly IO-360-A1A. Compression on the engine is 74, 76, 74, 76. The
owner refuses to negotiate on the basis of these concerns and leaves
me nothing to mitigate some of the potential risk.

I spoke with a local mechanic today and his opinion is that it should
give pause but the engine may be fine and was seemingly encouraged by
the compression numbers. He recommends an oil analysis. His opinion
is the biggest potential unseen danger stems from the cam and an oil
analysis would address this concern one way or the other.

Comments? Would you consider such a deal? The mechanic's advice seem
sound?


Greg

Newps wrote:
It's a Lycoming, compression is always good. You need to check the cam.
Lyc's lose their cams without use.

Believe me, the compressions were great on my engine up until the time
the cylinder blew. As Newps says, you need to take a look inside.
I'd particularly be worried about corrosion (cam and cyl) on an engine
that flies infrequently.

On 5/18/2007 8:22:50 PM, Greg Copeland wrote:

The
owner refuses to negotiate on the basis of these concerns and leaves
me nothing to mitigate some of the potential risk.

With the glut of aircraft on the market I would suspect you will find a much
less risky purchase.

From what I have learned over the last six years as a single engine aircraft
owner, I would walk away from this sale without a second thought. You have
every right to be concerned about an engine that has seen such little use
over such a long period of time.


--
Peter

On 18 May 2007 17:22:54 -0700, Greg Copeland wrote:

I've been shopping for a plane for a while. I'm hoping I found the
one but the engine has given me pause. The engine is 17-years old.
It has ~700 hours on it. The average per year is only 49hr/year. Two
years during that 17, the plane did not fly and I'm guessing it was
not pickled. The latest it sat was in 2000. During the last 6 years,
the plane has mostly flown some 32hrs/year on average. The engine is
a Ly IO-360-A1A. Compression on the engine is 74, 76, 74, 76. The
owner refuses to negotiate on the basis of these concerns and leaves
me nothing to mitigate some of the potential risk.

I spoke with a local mechanic today and his opinion is that it should
give pause but the engine may be fine and was seemingly encouraged by
the compression numbers. He recommends an oil analysis. His opinion
is the biggest potential unseen danger stems from the cam and an oil
analysis would address this concern one way or the other.

Comments? Would you consider such a deal? The mechanic's advice seem
sound?


Greg

This really falls into the area of negotiating strategy rather than "would
you buy this engine".

In your position, I would figure out how much *I* thought the plane might
be worth assuming the engine will require a complete overhaul, including
accessories, fuel and oil lines, mounts, cooler overhaul, etc. Possibly a
prop overhaul also? Or maybe the Hartzell prop hub needs to be replaced
because of the new A/D?

Then I would inform the seller how much I would be willing to pay for his
aircraft. I would not necessarily go into any details as to how I arrived
at that figure, although I might depending on the specifics of what
happened next.

It is the seller's right to ask whatever he wants for his airplane, and it
is my right to not pay any more than I want to. But, if you run the
numbers, you might discover that his asking price is such that you can live
with it, even with overhauling the engine right after purchase.

So far as oil analysis being able to predict whether a new cam will be
required in the next 25 hours or so -- it won't. And I've flown behind a
Lyc IO360A1A for the past 30 years or so, and gone through several
camshafts during that time!

FWIW, Lycoming recommends overhaul of that engine at 12 years, if it has
not met the flight time limits. Of course, under Part 91 non-commercial
flying, it is perfectly *legal* to overhaul "on-condition".

But I would only purchase that aircraft assuming I was going to do a
firewall forward overhaul soon after.

I would not rely on the "local mechanic's" opinion to conclude that the
engine will not require an overhaul in the near future. (Unless he's
willing to give you a warranty, and you think you can enforce it, of
course).

Good Luck!
--ron

On May 18, 5:22 pm, Greg Copeland wrote:

I spoke with a local mechanic today and his opinion is that it should
give pause but the engine may be fine and was seemingly encouraged by
the compression numbers. He recommends an oil analysis. His opinion
is the biggest potential unseen danger stems from the cam and an oil
analysis would address this concern one way or the other.

Comments? Would you consider such a deal? The mechanic's advice seem
sound?


Oil analysis is a trend tool. Even the folks that sell the service
will tell you that. A single oil analysis won't tell you much unless
the engine is shedding a prodigious amount of metal (which you should
be able to see by cutting open the oil filter). On Lycs that don't
get much use, I'd pull a cylinder or two and inspect the cam directly.

I know too many people that have bought underused engines that
looked good at inspection, only to have the results of internal
corrosion start showing up after they started flying it regularly.
Personally, with the airplane market heavily favoring the buyer these
days, I'd look elsewhere. This engine might be quite servicable, but
the seller is asking you to stake your money that it is. There's no
down side for him.

John Galban=====N4BQ (PA28-180)

In article . com,
Greg Copeland wrote:

I've been shopping for a plane for a while. I'm hoping I found the
one but the engine has given me pause. The engine is 17-years old.
It has ~700 hours on it. The average per year is only 49hr/year. Two
years during that 17, the plane did not fly and I'm guessing it was
not pickled. The latest it sat was in 2000. During the last 6 years,
the plane has mostly flown some 32hrs/year on average. The engine is
a Ly IO-360-A1A. Compression on the engine is 74, 76, 74, 76. The
owner refuses to negotiate on the basis of these concerns and leaves
me nothing to mitigate some of the potential risk.

I spoke with a local mechanic today and his opinion is that it should
give pause but the engine may be fine and was seemingly encouraged by
the compression numbers. He recommends an oil analysis. His opinion
is the biggest potential unseen danger stems from the cam and an oil
analysis would address this concern one way or the other.

Comments? Would you consider such a deal? The mechanic's advice seem
sound?


Greg

I would assume that the engine should be torn down and overhauled.
Lycomings, especially, suffer from #1 and #2 cam erosion, due to
condensation in the upper front of the crankcase. Oil analysis may or
may not spot a problem here.

Cylinders may be pitted due to condensation/atmospheric pumping.

Some Hartzell propellers have a mandatory 5 year inspection cycle.

If the plane has sat outside, airframe components may suffer from
corrosion. Paint may need replacement.

Orval Fairbairn wrote:
Lycomings, especially, suffer from #1 and #2 cam erosion, due to
condensation in the upper front of the crankcase.

Curious. Why would you get more condensation in the upper front part of
the crankcase than anywhere else?

In article ,
Roy Smith wrote:

Orval Fairbairn wrote:
Lycomings, especially, suffer from #1 and #2 cam erosion, due to
condensation in the upper front of the crankcase.

Curious. Why would you get more condensation in the upper front part of
the crankcase than anywhere else?

That is the area where ventilation is least -- also, the highest point
of the inside of the crankcase when the aircraft is at rest.

And....

When preheating, the metal propeller is a HUGE heat radiator, keeps
the front of the engine cooler than the rest, hence more
condensation in that area....

Some get mittens for their props...

Dave


On Sun, 20 May 2007 14:00:11 GMT, Orval Fairbairn
wrote:

In article ,
Roy Smith wrote:

Orval Fairbairn wrote:
Lycomings, especially, suffer from #1 and #2 cam erosion, due to
condensation in the upper front of the crankcase.

Curious. Why would you get more condensation in the upper front part of
the crankcase than anywhere else?

That is the area where ventilation is least -- also, the highest point
of the inside of the crankcase when the aircraft is at rest.