Nasa Icing courses

There is also the fact that the oil pump is at one end of
the engine and the cam shaft lobe that fails is probably at
the other [a guess] and the oil takes some time to reach the
journal and establish a full oil bearing.

Add a little sludge, maybe some cold oil and an over-revved
engine, and you get cam lobe /journal failure or the lifter.

Pilot error due to poor operation.


--
James H. Macklin
ATP,CFI,A&P

--
The people think the Constitution protects their rights;
But government sees it as an obstacle to be overcome.
some support
http://www.usdoj.gov/olc/secondamendment2.htm
See http://www.fija.org/ more about your rights and duties.


"George Patterson" wrote in message
news:J11wf.517$sa4.41@trnddc07...
| Jay Honeck wrote:
|
| Does anyone *really* know what causes a camshaft to fail
like this? I read
| about it happening with alarming regularity, and it's
never attributed to
| anything in particular.
|
| In the absence of some catastrophe, such as a bent
pushrod, this is generally
| caused by not flying enough. The layer of hardened steel
on a camshaft is fairly
| thin. Let the plane sit long enough, and rust will form.
When the engine starts
| again, the rust is worn away, making the thin layer of
hardened steel thinner.
| The worst wear points, of course, are the tips of the
lobes. Once the hardened
| steel wears through, the softer steel underneath goes
pretty rapidly.
|
| "So why not build the shaft entirely of hardened steel?",
I hear you cry. That's
| because the harder steel is, the more brittle it becomes.
The best strength
| comes from this sort of lamination of hard and soft
steels.
|
| George Patterson
| Coffee is only a way of stealing time that should by
rights belong to
| your slightly older self.