First, I must say that I am not a mechanic by any stretch. I am just
learning this stuff, so I might have misunderstood what the shop was
telling me. Hopefully, an expert will chime in here soon and explain
this a bit better.

That said, I am not sure I understand what is you did not understand.
It seems to me that if the crank shaft breaks, you end up with
essentially two engines: a set of cylinders running one side of the
shaft break and the rest running the other side of the shaft break. So,
it would seem that some cylinders are running the engine parts (oil
pump, magnetos, etc) and the others are running the prop. Of course, if
the break occurs right next to the prop, then the prop would stop. If
it breaks behind the main rear bearing, then all of the engine
accessories stop (and thus the engine stops soon after). Also, I should
point out that the shop speculated that even though the shaft broke,
that in might have been partially connected through friction (since the
break was not a 90 degree shear break).

Now, I will hasten to add that my understanding of crank shaft operation
may be overly simplistic, so again, I will defer to expert opinion as it
comes in. I am sharing all of this to get as much out of it as a
learning experience as I can.

-Sami
N2057M, Piper Turbo Arrow III

Bill Hale wrote:
"O. Sami Saydjari" wrote in message ...

Updated update: I was just down at the overhaul shop today )Poplar
Grove). The crank broke just in front of the rear main bearing. So the
front 5 cyclinders were running the prop and the rear-most cylinder was
running the gearing to the rest of the engine. They said the whole shop
stopped to come take a look at the engine! They were astounded that it
ran 10 minutes after the crank broke (which is exactly the time I needed
to get to the nearest airport and land safely).


How can this be?? The crank drives the camshaft then the mags run from
gears that mesh with the cam gear... at least it's like that on every
other continental I've seen.

So the cam and maqs and oil pump quit working if the crank breaks.

It would windmill, however. Until it locks due to lack of oil.

What don't I understand? If there was metal in the oil filter, the
oil pump must have been running.

Bill Hale