Many years ago, we had a series of
engine stoppages with an early Jab.? We tried all manner of tricks
to prevent carb icing, and I used to climb up to several thousand
feet, throttle back and decend to see if we had affected a cure
after every modification.? The engine only ever stopped on me? in
the circuit, never during these tests!? Frequently stopping on the
"final glide".? I got to the state where I refused to go around,
no matter how bad the landing, as opening the throttle would cause
the engine to splutter and die every time.
The final cure was to fit small electric heaters onto the body of
the Carb.? I would switch them on before every descent and switch
them off for normal flight and this cured the problem for me.? The
sump oil carb heat did not work adequately in the UK climate
whilst descending.
Another pilot said, subsequent to his accident, that he left the
heater turned off "to save the battery" he restarted the engine
three times in the circuit after it had stopped, but still failed
to turn on the heater. (This same mentality causes drivers to
drive on parking lights when in their cars, which makes them
virtually invisible after dark.) ? The final stoppage was too low
to affect a restart and the crash wrote of the aircraft.
The problem with the carb was finally cured with electric carb
heat, but there is no cure for stupidity!
Cheers,
Mo Davies.
.? Justin Gregoris wrote:
Good afternoon Gents
Background: Jabiru 2200 Bing carburetor was fully serviced for
the first time in 14 years by Rotax dealer; also who was my
flight instructor who taught me how to fly.
Since the carburetor was off, I decided to route new fuel lines
since I did not have a bypass line with a one-way check valve. I
also replaced my fuel pump with a brand new fuel pump with a
built-in check valve.
Yesterday, I put fresh fuel in and started up the motor for
about 10 or 12 minutes and then did a static run test. I went
full power for about 10 seconds and then slam their throttle
right down to idle to see if it would stall. It did not install.
I did this multiple times on the ground.
Today, I fired up the engine and warmed it up as usual and then
did a static run before my first flight of the year. I was
flying with a pilot that has 48 years of flying experience in
over 30 aircraft.
The takeoff went great but then the master breaker popped as
well as my 3 amp transponder breaker also popping. I don't know
why this happened as it never happened before but I pushed back
in the master breaker and we continue flying without any issues.
As we were approaching to land my airplane everything was going
well. I was coming in a little too fast so as soon as I was over
the runway I moved the throttle right back to idle position at
which point I flared too early and the airplane ballooned a
little bit but nothing crazy. When a lightly kissed the ground
and the nose went up the engine all of a sudden installed and
the propeller stopped turning. Luckily at that point I was able
to land without any hard effects but both of us were extremely
shocked the engine stalled. Thank goodness it was literally
right at the end. It easily fired back up and then I did another
static run and slammed it back to idle and it did not stop.
I am scratching my head as to why it's stalled. It has never
ever done this before. I forgot to use electric boost pump when
I was landing which may have helped the issue not even happen?
Perhaps it was an air bubble or air pocket that was trapped in
the brand new fuel line?
I do not have any fuel leaks right now or smell any fuel and all
my brand new lines are bone dry.
I think it is coincidental that the master breaker and the
transponder breaker popping has nothing to do with the engine
stopping. But that has never happened to me either.
yesterday I noticed my engine idling at about 12:00 or 1300 RPM
so this morning I took out my 7 mm wrench to try and lower the
idle stop screw at which point it did and now it idles at about
1,000 RPM.
Any guidance as to the culprits of the engine stopping is
greatly appreciated as I intend to fly in 2 days from now and do
not want this to happen again. Thank you
?
