WingFlaps wrote in
:

On Feb 15, 9:12*am, Gig 601XL Builder
wrote:
WingFlaps wrote:
On Feb 15, 8:11 am, Gig 601XL Builder
wrote:
WingFlaps wrote:
That apart, I'd like to dig a bit deeper into this reliability
issue. What percentage of Lycs or Cons mahe it to TBO without
major part replacements (such as cylinders, cylinder heads,
magnetos etc.). Put another way, is there anyone here who has
_ever_ seen one go to TBO without major working?
Cheers
Of course there are I've seen Lyc and Conts go WAY over TBO.
Anyone tha
t
* has spent much time around personally owned aircraft (Not
Rental) h
as
seen the same.

Now I could be wrong, but I thought not making TBO implies a bad
failure? *So in my thinking, my question remains since an engine
may make TBO even though it has had major parts (such as a cylinder
heads/ baarrels) replaced... If you know a few engines that have
only ever had plugs replaced in 2000 hours then that's great but I
would still like to know roughly what % that is. If you have the
magazine you refer to perhaps you could look up the relevant figure
for me? Another way of finding this out could be to look at how
many cylinder heads and barrels are sold compared to crankshaft
service kits (if there is such a thing). Even this would
underestimate the true rate of engine fails at annual as cylinders
can be easily rehoned to raise compression. Is 2000 hours is more
of a myth than reality? Is there a LAME here who could estimate how
many plane engines he's had to strip compared to ones he could just
leave alone for 2000 hours?

Cheers

You keep moving the bar. YOu asked, "is there anyone here who has
_ever_ seen one go to TBO without major working?" And the answer from
myself and others was yes, lots.

I' have know idea if the the percentage data you want is out there
but


Well if you know the complete history of a 2000 hour engine that never
had anything but plugs replaced then as I said, that's great. But if
such anecdotal evidence is what you base reliability figures on then
I, personally, would not have much faith in them. That's my point. I
really don't have any axe to grind on engine type but am trying to be
objective -if that's OK with you? The heavy use Lycoming engines I
have seen all seem to be well down on compression by 1200 hours and
that is not a good look for them to reach 2000 -but I have only a
sample of about a dozen. Of course we'll ignore the complete recall of
cylinders that took place recently... So, is 2000 hours service
normal?

In my experience, yeah. They mostly make it that far.


As for being stuck on the idea that one engine type is superior it's
not me as I'm only trying to glean _facts_ and don't I own anything -
what about you? Right now I am looking at the diesel STC for Cessnas
so this is not trivial but a near $1M question.


I kinda prefer to fly Continental eningenes between the two. i couldn't
tellyou why, though. Haiving said that, I'd still prefer any radial over
either! ( except of course an w670 or r 680)




Bertie