My partner and I just purchased a Piper Warrior from California. All
the compressions on the engine are 72 or better. We test flew for about
two hours and found no problems. Just recently she was taken in for the
Canadian inspection. The AME in Brampton told us that the compressions
were good but one cylinder was cracked. What I would like to know is
how can you have good compressions with a cracked cylinder. Also how
can you determine that a cylinder is cracked without dismantling the
engine. The aircraft is a PA28-151, with a 0-320. If anyone can clairfy
this issue I would really appreciate it. Can you fly the plane this way
or is it dangerous.

Thanx Jurgen..

"av8tr" > wrote in message
oups.com...
> My partner and I just purchased a Piper Warrior from California. All
> the compressions on the engine are 72 or better. We test flew for about
> two hours and found no problems. Just recently she was taken in for the
> Canadian inspection. The AME in Brampton told us that the compressions
> were good but one cylinder was cracked. What I would like to know is
> how can you have good compressions with a cracked cylinder.


It is very simple. I did an annual inspection on my 182 before leaving for
Oshkosh and on the way home a cylinder cracked to the point that the intake
and exhaust manifolds were the only thing holding it onto the engine.

Depending on where the crack is, it could be completely below the piston
rings (as was mine) and you would never notice it on a compression check.
Even with a mirror inspection (as was mine) you could not detect an
incipient crack that had not yet broken through the surface of the cylinder
wall.



Also how
> can you determine that a cylinder is cracked without dismantling the
> engine.

If the crack is all the way through the cylinder, you can certainly see an
oil line that would bear further investigation. If it is NOT through the
cylinder, the only way is to do an internal AND external visual AND
particle/glow/xray inspection of the part in question (removal from the
engine necessary).


The aircraft is a PA28-151, with a 0-320. If anyone can clairfy
> this issue I would really appreciate it. Can you fly the plane this way
> or is it dangerous.

YOu can't be serious, can you?

Jim

In article . com>,
"av8tr" > wrote:

> My partner and I just purchased a Piper Warrior from California. All
> the compressions on the engine are 72 or better. We test flew for about
> two hours and found no problems. Just recently she was taken in for the
> Canadian inspection. The AME in Brampton told us that the compressions
> were good but one cylinder was cracked. What I would like to know is
> how can you have good compressions with a cracked cylinder.

It depends on where the crack is and how extensive it is.

One year an IA was "inspecting" my airplane and found two cracked
cylinders. Both cracks were very small. I had not noticed any performance
issues with the airplane prior to bringing the airplane in for the annual.

> Also how
> can you determine that a cylinder is cracked without dismantling the
> engine.

visual inspection. Open the cowling and look at the cylinders.

Good luck.

--
Bob Noel
Looking for a sig the
lawyers will hate

"RST Engineering" > wrote in message
...
>


> The aircraft is a PA28-151, with a 0-320. If anyone can clairfy
>> this issue I would really appreciate it. Can you fly the plane this way
>> or is it dangerous.
>
> YOu can't be serious, can you?
>
> Jim

If this is his first experience with a cracked cylinder, I'm sure he is
serious. How else would one know?

Having owned a Warrior with the same low powered motor in it I am
willing to bet the crank is in the exhaust port and it is running up
toward the guide boss. That crack will not cause compression issues
but left unattended it will eventually cause the exhaust seat and or
the guide to come loose. Not a good thing.. My guess the A&P saw it
when he removed the exhaust system for some reason. Fill us all in on
the location of this crack in your new bird please...


av8tr wrote:
> My partner and I just purchased a Piper Warrior from California. All
> the compressions on the engine are 72 or better. We test flew for about
> two hours and found no problems. Just recently she was taken in for the
> Canadian inspection. The AME in Brampton told us that the compressions
> were good but one cylinder was cracked. What I would like to know is
> how can you have good compressions with a cracked cylinder. Also how
> can you determine that a cylinder is cracked without dismantling the
> engine. The aircraft is a PA28-151, with a 0-320. If anyone can clairfy
> this issue I would really appreciate it. Can you fly the plane this way
> or is it dangerous.
>
> Thanx Jurgen..

> av8tr wrote:
> > My partner and I just purchased a Piper Warrior from California. All
> > the compressions on the engine are 72 or better. We test flew for about
> > two hours and found no problems. Just recently she was taken in for the
> > Canadian inspection. The AME in Brampton told us that the compressions
> > were good but one cylinder was cracked. What I would like to know is
> > how can you have good compressions with a cracked cylinder. Also how
> > can you determine that a cylinder is cracked without dismantling the
> > engine. The aircraft is a PA28-151, with a 0-320. If anyone can clairfy
> > this issue I would really appreciate it. Can you fly the plane this way
> > or is it dangerous.
> >
> > Thanx Jurgen..

During an import inspection the mechanic may have seen a bit of
exhaust staining on the cylinder head. He would look for a crack during
the compression test using a soap and water mix on the head and upper
cylinder. Lycoming cylinders can crack between a sparkplug hole and the
exhaust port, and it might not leak enough to show up on the
compression tester but will sure make some bubbles in the soap. You
can't just let it go, either.
When we do the Canadian AD that applies to all exhaust systems
that take cabin heat from the exhaust system (CF90-03R2), we use the
soap and water on all the exhaust components and frequently find small
cracks before they get serious (and expensive).
Be thankful for a mechanic who keeps you safe. There are a few
who will try to rip you off, but most of the rest just don't want to
get blamed for overlooking or ignoring something that caused an
accident.

Dan

wrote:
> When we do the Canadian AD that applies to all exhaust systems
> that take cabin heat from the exhaust system (CF90-03R2), we use the
> soap and water on all the exhaust components and frequently find small
> cracks before they get serious (and expensive).

We do the same in the U.S. but at annual, not under an AD.

-Robert

as an owner, i've resigned myself to the fact that these things just
shed jugs and that's the way it is. that's one of the reasons i chose
to have 6 little bitty jugs instead of 4 big ones. if one of mine gets
to feelin pooly it's no big deal. i just replace it, i did not need
that thousand-dollars, did i?

your ship is grounded till repair.

dan


av8tr wrote:
> My partner and I just purchased a Piper Warrior from California. All
> the compressions on the engine are 72 or better. We test flew for about
> two hours and found no problems. Just recently she was taken in for the
> Canadian inspection. The AME in Brampton told us that the compressions
> were good but one cylinder was cracked. What I would like to know is
> how can you have good compressions with a cracked cylinder. Also how
> can you determine that a cylinder is cracked without dismantling the
> engine. The aircraft is a PA28-151, with a 0-320. If anyone can clairfy
> this issue I would really appreciate it. Can you fly the plane this way
> or is it dangerous.
>
> Thanx Jurgen..

> as an owner, i've resigned myself to the fact that these things just
> shed jugs and that's the way it is. that's one of the reasons i chose
> to have 6 little bitty jugs instead of 4 big ones. if one of mine gets
> to feelin pooly it's no big deal. i just replace it, i did not need
> that thousand-dollars, did i?

Knock on wood, I've had good luck with our Millenium cylinders thus
far... They're a little beefier in areas that are known to crack.
--
Jay Honeck
Iowa City, IA
Pathfinder N56993
www.AlexisParkInn.com
"Your Aviation Destination"

houstondan > wrote:

> i just replace it, i did not need
> that thousand-dollars, did i?

LOL! Just dropped a couple AMUs on AP-related repairs, so your comment is
especially timely.

--
Peter