All who like to know what was it
***
One week ago on Sunday I looked, found and solved the source for
vibration as follows:
First I checked the overall appearance of the plane =93 good
Then I took the prop for a closer check and drove the blades to their
finest positions =93 all very exactly 17 degrees (measured from
the tip end).
Then I drove them to the coarsest position =93 all were again same
and 29,5 degrees,
Opened the cowlings =93 just normal inside.
Took off all the sparking plugs =93 one until another were just
great =93 colour like mild milk coffee...
- until I took of the last (!) one: that was #3 (stbd side, rearmost)
and lower one: it was sky blue (a colour like RAL 5015 or Pantone
2925C).
It /they have been on service 57 hrs only.
Attached a pic of it (it was not so easy to photo it to get a correct
colour!).
I replaced all the plugs for new. That was it. As I wrote earlier
=93 My Europa was after service just great.
***
My mistake: I did not try during the flight one week ago the magnetos A
and B alone. I could not imagine that would be a solution for a smoother
ride. You remember =93 one power selection and one rpm-selection
only together was acceptable to continue the flight with a reasonable
vibra only.
***
How could loosing only one plug to make such a hard situation? My only
guess is that it was detonation; below and over certain rpm=C2=B4s and
map=C2=B4s the engine was very unhappy. Why so =93 I am sure
someone of you can explain it. Certainly the plug has been very hot.
***
I consulted a Finnish Rotax agent: during a last decade he remembered
only another case loosing a spark plug from Rotax. That case the spark
was only dead and no noticeable problems during the flight. His ten
years are equal of well over 200.000 hrs of Rotax flight time (200
planes x 100 hrs /year x 10 year).
***
Dear competitors: I got several answers. Some of them are a bit funny
but all are valuable. Thanks for great inputs. All of you, also those
privat answers.
Only one of you guessed the right answer. That was Bob Yearly by writing
as follows, that was a great list for all of
us, thank you.
Many things to check.
Carbs:
Check for a vacuum leak or a carb intake or carb to manifold leak.
Especially since it seems to have just started and abates at low power
setting.
Check carb balance.
Engine Electrics:
First check ignition A and B separate.
Second check plugs, check coil. (one bad coil really shakes also)
Pull plugs and look for differences.
Fuel :
Check carb float bowls for dirt.
Check fuel pressure regulator for 914
Finally your fuel pump delivery pressure.
Exhaust:
Check no exhaust failure. Look at the entire exhaust for soot, looseness
or failures.
Regards,
Bud
***
Problems: The Rules: one single guess per person, please.
So, Bud is not a winner but that is not a problem for him I am sure.
What is the jury=C2=B4s decision? All of you (who gave a guess or more)
will get a little surprising shipment from Finland: just let me know
your exact address info details direct to
info@rwm.fi
Also the daughters.
Thanks,
Terveisin,
Raimo Toivio
RWM-SYSTEMS
"=C3=A4lyk=C3=A4st=C3=A4 informaatiotekniikkaa vuodesta 1980"
37500 Lemp=C3=A4=C3=A4l=C3=A4
FINLAND
p. 03 - 3753 777
f. 03 - 3753 100
www.rwm.fi
info@rwm.fi
From: Bud Yerly
Sent: Wednesday, October 05, 2011 9:15 PM
Subject: Re: Europa-List: Heavy In-flight Vibration Riddle
Many things to check.
Carbs:
Check for a vacuum leak or a carb intake or carb to manifold leak.
Especially since it seems to have just started and abates at low power
setting.
Check carb balance.
Engine Electrics:
First check ignition A and B separate.
Second check plugs, check coil. (one bad coil really shakes also)
Pull plugs and look for differences.
Fuel :
Check carb float bowls for dirt.
Check fuel pressure regulator for 914
Finally your fuel pump delivery pressure.
Exhaust:
Check no exhaust failure. Look at the entire exhaust for soot,
looseness or failures.
Regards,
Bud
----- Original Message -----
From: Raimo Toivio
To: europa-list@matronics.com
Sent: Saturday, October 01, 2011 3:44 PM
Subject: Europa-List: Heavy In-flight Vibration Riddle
All
I have hope-so a nice riddle for you.
Maybe all the answers are useful =93 let=C2=B4s collect them
all:
***
Yesterday I took off from a very remote /small /windy (90 degrees 12
knots and gusting MUCH) grass strip. Soon until well over the ground at
altitude +500 feet with full power and 2nd fuel pump still on and gears
up I felt suddenly let us say medium or more shake and vibration. My
immediate reaction was to go around and land immediately but abandoned
because wind was so furious and I felt I cannot do that (a succesful
landing).
I decided to try to fly to the next possible sensible airfield EFHV
which was 10 minutes apart.
Those minutes were long: I put my prob (Airmaster CS) to manual and
drived it from fine to coarse, tried all the power settings and also a
2nd fuel filter. Finally I noticed that when prop was in a climb mode
(in my case 5400 rpm /Rotax 912S) and MAP around 20 inches I got quite a
comfortable flying mode and I headed straight home. My airspeed was w
that selection about 110 knots but because of a strong headwind GS was
only about 70 knots (wanted to be clearly over the ground at 3000 ft
because it was well over sunset and totally dark, yesterday we got
sunset around 1600 Zulutime and time was well over 1630 when flying).
So, I pushed home one looooong hour. All the aerodynamics were well. I
was a bit worried my engine will separate or so. When trying to push
more pwr it was more vibra and when trying to pull less pwr same. I
Followed a main highway and decided to land there if feeling so. Cars
there with lights are almost like a lighted runway...
Finally landing to the EFTP flawlesly.
***
Today we had a FHGP (Family Hangar Grill Party). I tried to check my
plane as well as I can. I found something. Very small evidence but
something anyway. I tried to fix it and had a test run. I elected to go
to fly =93 hey I am a test pilot who else =93 and She was
better than ever!
I managed to do 2 touches and goes when C172 did one with same runway.
140 knots during downwind makes me always happy.
***
So =93 dear Ladies and Gentlemen =93 what was wrong?
It would be nice and very life-useful to hear your opinions or guesses
what was wrong.
***
The Rules: one single guess per person, please.
The Prize: The Best Guess will get a Very Special Xmas Present from
Finland!
***
I will let you know a solution after a week =93 be patient.
Have a nice weekend and
Cheers, Raimo Toivio
Europa XS Mono OH-XRT #417
Updated flight hours /landings: 258,3
37500 Lempaala
FINLAND
p +358-3-3753 777
f +358-3-3753 100
toivio@fly.to
www.rwm.fi
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