Brave man to fess up
-----Original Message-----
From: owner-europa-list-server@matronics.com
[mailto:owner-europa-list-server@matronics.com] On Behalf Of Raimo Toivio
Sent: 15 November, 2011 14:12
Subject: Re: Europa-List: Re: Heavy In-flight Vibration Riddle /The Solution
/The Winner(
Dear Frans, Remi, Brian and all who were
interested
Thank you for your Very interesting messages (they
are below).
During last three days my engine (912S) has got
his 250 hrs service (in fact 50 hrs service only)
+ max and full care inspection because of the
topic: Heavy In-flight Vibration Riddle.
Before that (after my hazard and when changing
sparks only) I had flown flawlessly 2 hrs 25
minutes w/o any problems and The Engine has
performed great.
The inspection and service was completed w the
best pros in Finland available (I was there also,
just looking behind their shoulders, do not
worry).
1) Engine is like a new one and between The
Factory Limits and Measurements excluding
following
2) Right carburrettor, 2nd float, "some" material
has "obviously" separated, gone and disappearred
somewhere.
- pls notice: these floats have checked last
spring when completed 200 hrs engine service. They
looked like ok then but did not checked very
carefully, of course.
- that little "separated" part could be also a
malfunction of production, maybe it has never been
there
3) That blue colored spark plug was really totally
dead (it was NGK R DCPR8E)
What ideas we got?
A) if some part of the float separated during the
flight it could have blocked partially fuel flow.
After case it could have gone through the system
and no problems anymore. If that is so, changeing
sparks meaned nothing - a new start up the engine
meaned.
If that is so, please check your floats. For your
information, there was a Service Bulletin about 15
years ago about those floats. I have not checked
it so far (and that should be nothing in my case
[engine 2006] but who ever knows).
B) this case is a bit embarrassing but I am brave
enough to report it to you (could be worth of it
for some of you).
We tried the engine with that broken spark. As
Remi writed A single misfiring spark plug on one
cylinder cannot cause the high level of vibration
I have experienced.
Confirmed. It cannot. I tried. But, what if (after
checking the mags) I took off with one magneto
only! And loosed one spark just after take-off.
Then I had only three sparks!
I have to say - I tried it today - and the The
Vibras were very known. I have been there. If that
is really so, I flied about one hour with three
sparks only (there was a heavy head wind but I
still was wondering where all the power has gone).
That is also the well known CS prop syndrom: The
RPMs are fixed: it is not so obvious to see engine
limitations.
***
What can I say:
* check out your floats in the carburrettor
chambers (well, Rotax owners at least)
** double check before take-off you have selected
dual magnetos: if you loose one spark w two
magnetos you will not notice but if you loose one
spark with one magneto you will surely notice. And
that will vibra you!
I have a Cessna type key operated magneto. It is
not so easy to see what magneto(s) is (are) valid:
A, B or Both. If you are building a plane, have
two separate switches. They are easy to confirm;
both upp (and a secure latch down)!
I took off after sunset and was a bit hurry and
maybe also more all less nervous. That is a
typical start upp for a chain which will easily
lead up to the accident.
In my case, what about loosing 1/4 spark during
take-off - that was a very short grass strip.
*** if you have engine problems during a flight
try always magnetos. That is what you have learnt
when flying your PPL. I did not by purposely but
I was (maybe) wrong.
_____________________
Trying to be a better pilot. A flight today was a
last one I think until a year or even more has
gone and the new season 2012 will begin...
_____________________
The Competition has got The Winners - there are
three of them.
I will publish The Names of The Winners ( I assume
I am free to do that ) very soon.
Cheers, Raimo Toivio
Europa XS Mono OH-XRT #417
Updated flight hours /landings: 258,15 /466
37500 Lempaala
FINLAND
p +358-3-3753 777
f +358-3-3753 100
toivio@fly.to
www.rwm.fi
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