Showing metal at 1,100 hours

"Maule Driver" wrote in message
news
I've put over 1,000 of the 1,100 hours on this new O-360-C4f. Changed the
oil religiously. I didn't baby the engine but didn't abuse it either.
Always hangered etc.

My last oil analysis showed a doubling of iron 47.9ppm to 101.0ppm with 36
hours on the oil. Everything else normal. We did the filter and we found
very fine iron filings or dust with a magnet. How much - hard to tell.
No chunks though.

We're thinking cam and lifter.

My mechanic is playing it safe - called Signature and Mattituch who
recommended no more flying, split the case, and fix or overhaul.

I want some second opinions. I could fly 10 more hours and take another
look. We could pull a cylinder and check the cam I'm told.

I've read about Second OilPINION and Howard Felton - a knowledgeable
analysis of the metal seems like money well spent. Is he still in
business? Anyone know anyone else who can do this?

Any other factors? My exhaust manifold/heat exchanger broke and I flew
for 10 to 36 hours with it broken. Parts 'banging' around under the
cowling etc. Discovered it during oil change. I did let it sit without
running for 60+ days - a first for this aircraft.

Thoughts?

Maulesitter.

Since you let the aircraft sit for 60 days, is it possible (likely?) that
the metal you are seeing is simply the layer of rust that formed on your
cylinder bores?

KB

It does have mushroom lifters - my mechanic seemed to be very aware of
that fact but I didn't understand the ramifications.

wrote:
On Fri, 16 Dec 2005 23:24:45 GMT, Michelle P
wrote:


Maulesitter,
You do not need to pull a cylider to look at the cam.
Just pull the rocker arms, push rods, tubes and lifters. You can peer in
the hole with a flash light and mirrow.
Michelle


Unless it's one of the few Lycomings running around with
automotive-style barrel lifter bodies, the engine has mushroom lifter
bodies. The portion that rides on the cam lobe has a larger o.d. than
the rest of the body (and the corresponding hole in the crankcase).

TC

Denny wrote:
Another airplane on our field with 360 just lost the cam and lifter
last month and it caused big time damage while they piddled around
with, "well, lets fly it a while and look at the filter again."... The
lifter spalled off chunks shortly after that decision and the pistons
picked the debries up on the skirts and scored the cylinders... His
'repair' on a 700 hour engine is now $10K....

Pull a cylinder and borescope the cam... Not a lot of bucks or downtime
to do this and you can make an informed decision, not a guess...


That seems to be the most rational move to make at this point.

Kyle Boatright wrote:

Since you let the aircraft sit for 60 days, is it possible (likely?) that
the metal you are seeing is simply the layer of rust that formed on your
cylinder bores?

Possible? I certainly hope so. Likely? I don't know. Does anyone
doing regular oil analysis see this when their a/c sits idle for 60 days?

I realize that if I have a jug pulled and find nothing then I really
have a problem. What is it? Rust in the cylinder bores would be a
Christmas present.

Originally Posted by Maule Driver

Denny wrote:
Another airplane on our field with 360 just lost the cam and lifter
last month and it caused big time damage while they piddled around
with, "well, lets fly it a while and look at the filter again."... The
lifter spalled off chunks shortly after that decision and the pistons
picked the debries up on the skirts and scored the cylinders... His
'repair' on a 700 hour engine is now $10K....

Pull a cylinder and borescope the cam... Not a lot of bucks or downtime
to do this and you can make an informed decision, not a guess...


That seems to be the most rational move to make at this point.

as others have said, it's definitely a good idea to take a look at tha cam and lifters. but make sure you examine all of them - one can take a turn for the worst, while the other ones may not show much damage initially.

frank

Ouch,
Sorry. Guess pulling a cylinder is in order.
Michelle

Maule Driver wrote:

It does have mushroom lifters - my mechanic seemed to be very aware
of that fact but I didn't understand the ramifications.

wrote:

On Fri, 16 Dec 2005 23:24:45 GMT, Michelle P
wrote:


Maulesitter,
You do not need to pull a cylider to look at the cam.
Just pull the rocker arms, push rods, tubes and lifters. You can
peer in the hole with a flash light and mirrow.
Michelle



Unless it's one of the few Lycomings running around with
automotive-style barrel lifter bodies, the engine has mushroom lifter
bodies. The portion that rides on the cam lobe has a larger o.d. than
the rest of the body (and the corresponding hole in the crankcase).

TC

"Maule Driver" wrote in message
...
Kyle Boatright wrote:

Since you let the aircraft sit for 60 days, is it possible (likely?) that
the metal you are seeing is simply the layer of rust that formed on your
cylinder bores?

Possible? I certainly hope so. Likely? I don't know. Does anyone doing
regular oil analysis see this when their a/c sits idle for 60 days?

I realize that if I have a jug pulled and find nothing then I really have
a problem. What is it? Rust in the cylinder bores would be a Christmas
present.

210% increase in iron after sitting for 60 days? That doesn't sound very
likely to me, but then again I am not Howard Fenton. How many hours did you
fly after it sat for that long before you changed the oil and did the
analysis? Did you change the oil again after that? Try putting some rare
earth magnets on the filter housing, that will help collect any more of the
iron as well, give you another point of reference...

As others have stated, you are free to pursue whatever path you like. On
one extreme, tear the engine apart and overhaul before further flight.
On the other side, fly for a few more hours, take another sample to the
lab, and cut open the filter to see if you have any more "goodies"
lurking. One course is known to be expensive up front. The other may be
just as expensive in the long run. If something major breaks in the air,
the outcome may be more expensive. No way to know until it happens.

It sat for 60 days prior to the bad oil analysis? Some say that could do
it while another camp says that ain't it. Really? Show me the testing
data either way. What we get out of the engine manufacturers and oil
companies suggest that anything other than almost daily flight of 1 hour
risks corrosion buildup at some rate. Seems to suggest that, under the
right conditions, you could be seeing 2 months of inactivity that ended
up in the oil sump. Then again, they sell oil and engines (and have
nervous lawyers and insurance companies). I don't expect them to say
"leave the engine idle for long periods and it will probably be O.K.".

I have seen a Lycoming 360 locally that ground a cam lobe to 1/2 its
original height. It ran fine and idled O.K. It made what felt to the
owner as full power. No way to know how long it was in that condition.
Some suggest that once the hardened layer is ground off a surface, it
will "go quickly". Have any of the engine manufacturers or oil companies
done any testing in this area to see how quickly this may happen?

There are those who say that flying further risks "more" damage. Well,
if you split the case at 1100 hours, you may want to strongly consider
a major anyway. So, other than an off-airport excursion, I'm not sure
what would be different in several hours as far as the overhaul. Maybe
some crank scuffing? As you said, if you pull a jug and see nothing,
then what? The only way to "know" you are O.K. in that case is a major.

The thing that irks me when I get in this situation (like a cylinder
that might be going South) is that I cannot FLY the thing anywhere with
confidence except a local hop. Until the problem is resolved, the plane
is "down" as far as I'm concerned. No freedom to take a 400 mile jaunt
whenever I want is as good as no plane at all. Worse, in fact. I have a
potential financial liability simmering on the ramp that I cannot use.

Good Luck,
Mike

The thing that irks me when I get in this situation (like a cylinder that
might be going South) is that I cannot FLY the thing anywhere with
confidence except a local hop. Until the problem is resolved, the plane is
"down" as far as I'm concerned. No freedom to take a 400 mile jaunt
whenever I want is as good as no plane at all. Worse, in fact. I have a
potential financial liability simmering on the ramp that I cannot use.

Well put, Mike.

This is an aspect of ownership that is not often discussed. Nagging little
problems that, as a renter, don't even enter you mind, become HUGE deals as
an owner.

Right now I'm still chasing the "mystery oil leak" that leaves a little
puddle under my plane over time. Although it's not stopped me from flying
(the weather, on the other hand, *has*), it grates on me every time I open
the hangar door. It just isn't *right* -- even though everyone (including
my A&P) has told me that air-cooled engines just do this from time to time,
and you can spend $10K chasing it down, or you can live with it.

In the past, I've had alternator problems (will everything in the panel
suddenly die?), nose-wheel shimmy problems (will it get worse?), crunched
aileron sheet-metal (will it suddenly flutter without warning?), and a
plethora of smaller nits that drove me (more) nuts. The only solution is
to keep on top of them as they occur and fix them, one by one.

Maule Driver's case is, of course, far more critical. It'll be interesting
to hear what the inspections turn up.
--
Jay Honeck
Iowa City, IA
Pathfinder N56993
www.AlexisParkInn.com
"Your Aviation Destination"

Jay,
I had an mystery oil leak as well. It took me several weeks and wash
downs to find it.
When the engine was "cold" it did not leak. When it heated up it did.
Mine turned out to be a crack in the oil filter adapter housing. (you
and I have the same basic case design) Specificly the vernatherm
housing. When cold and retracted the crack was closed. When hot, the
vernatherm extended pushed the crack open. I followed the oil up as far
as I could. The problem was the oil was coming out under pressure and
going everywhere! I found it be looking with a mirror. What I saw was
missing paint in a area that did not have anything rubbing on it.
I was about to fully clean the engine have some one run the engine while
I looked for spraying oil.
I replaced it with a remote filter housing....
Michelle

Jay Honeck wrote:

The thing that irks me when I get in this situation (like a cylinder that
might be going South) is that I cannot FLY the thing anywhere with
confidence except a local hop. Until the problem is resolved, the plane is
"down" as far as I'm concerned. No freedom to take a 400 mile jaunt
whenever I want is as good as no plane at all. Worse, in fact. I have a
potential financial liability simmering on the ramp that I cannot use.



Well put, Mike.

This is an aspect of ownership that is not often discussed. Nagging little
problems that, as a renter, don't even enter you mind, become HUGE deals as
an owner.

Right now I'm still chasing the "mystery oil leak" that leaves a little
puddle under my plane over time. Although it's not stopped me from flying
(the weather, on the other hand, *has*), it grates on me every time I open
the hangar door. It just isn't *right* -- even though everyone (including
my A&P) has told me that air-cooled engines just do this from time to time,
and you can spend $10K chasing it down, or you can live with it.

In the past, I've had alternator problems (will everything in the panel
suddenly die?), nose-wheel shimmy problems (will it get worse?), crunched
aileron sheet-metal (will it suddenly flutter without warning?), and a
plethora of smaller nits that drove me (more) nuts. The only solution is
to keep on top of them as they occur and fix them, one by one.

Maule Driver's case is, of course, far more critical. It'll be interesting
to hear what the inspections turn up.