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Old 04-13-2005 | 01:12 AM
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Flyboy Dave
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From: Pinon Hills, CA
Default RE: ABC...wrong break in?


....back on topic for a moment....

ORIGINAL: downunder

You might find this interesting though.. http://home.kabelfoon.nl/~fiorimet/Index.htm
side bar "Running in" and then the third para.
I found some interesting info there, downunder....

Start the engine from rich and turn the needle slowly in, easy into resonance,
but keep relatively rich, and release quickly. Air running for the first flights should be
slightly four stroking.
Unless my reading comprehension has taken a severe dive, it appears that this
racing engine manufacturer is saying that his super high strung engines...."should
be run in the air....with the engine fourstroking for the first flights".

Hmmmmmm....that's creates a dilemma for the "four stroking your engine will
ruin it crowd".

Find a prop that runs between 28500 and 29500 on the ground. Try to
keep ground running to a minimum, peak rpm less than 3 seconds, then
immediately rich again. Try to get the engine in resonance by turning the needle
from rich all the time. Always start the cold engine with a needle setting 1/2 or 1
turn rich!
WOW !! ....one full turn out....that rich? Man, I hope that engine doesn't get
"ruined"....what a shame.

Be aware of the fact that wear highly coincides with high temperatures
and these don't happen in the air normally, but during ground running at peak
power with flying props. So:
Try to start your engine in competition as late as possible, try to turn the needle
to its right setting just before release and keep it as rich as possible until that
moment
Wait a minute....this manufacturer says that it's a "fact that wear highly coincides
with high temperatures". The doomsday folks are saying that wear and damage
happens from running the engine too rich. (cold) It looks like we have another
conflict here, huh ?

I think I will have to agree with the man, because as a mechanic myself I know
that friction and wear comes from heat....not cold....or as Rossi calls it....

....greasy. (running rich)

FBD.