Kingsley=0Acan't remember but did you check the carbs? Standing for a coupl
e of years isn't =0Agood, all sorts of crap comes out of the fuel including
sometimes bacteria/yeast =0Adeposits which can block small jets in the car
bs=0AI just cleaned my Andair gascolator after a year with not much running
and that =0Ahad a fair amount of sludge in it.=0AGraham=0A=0A=0A=0A=0A____
____________________________=0AFrom: Kingsley Hurst <kingsnjan@westnet.com.
au>=0ATo: europa-list@matronics.com=0ASent: Saturday, 13 August, 2011 12:14
:19=0ASubject: Re: Europa-List: Re: Europa-List Digest: 2 Msgs - 07/25/11
t.com.au>=0A=0AFellow Listers,=0A=0AAlmost 3 weeks ago, Tony Renshaw posted
the following plea on my behalf. My =0Aapologies for not repsonding befor
e this but circumstances have prevented me =0Afrom doing so.=0AI would sinc
erely like to thank those who came forward with suggestions which =0Aare no
w repoduced below together with my responses / comments. The long and the
=0Ashort of it is that given the remoteness of our landing aerodrome, the l
ack of =0Atesting equipment and time constraints, we left the aircraft than
kfully in a =0Ahangar and intend returning soon to retrieve it with my trai
ler.=0A=0ATony's posting . . . .=0A> I've got a mate, who we all know, King
sley, trying to fly a 914 a long distance =0A>downunder that is giving him
angst. Its running rough, real rough. It seems that =0A>at boost power it j
ust simply cuts out! Also, in cruise when going to climb =0A>power it has b
egun to run really rough. He is a long way from home trying to =0A>limp it
home, so any suggestions would be greatly appreciated. To elaborate, he =0A
>has flown it 2 hours on AVGAS with no obvious problem until going to climb
power =0A>when it ran so rough they had to pull the power back and land AS
AP, luckily with =0A>an aerodrome closeby. Now, it runs rough on the ground
too.not sure of what =0A>power settings but I recall they can't g
et boost happening. The local Rotax =0A>agent says that AVGAS with lead can
wreck a set of plugs in no time, so, they =0A>have a new set of plugs abou
t to be installed. Fuel will be drained and high =0A>octane super unleaded
mogas will be used instead. The system will be drained. =0A>So, I'm wonderi
ng if ASAP those in the know can beam downunder the "good goss" =0A>that ca
n help Kingsley get this bird home.=0A=0ABRIAN DAVIS . . . .=0A> Sorry to h
ear of Kingsley's troubles. It is difficult to diagnose such a =0A>problem
remotely but there are a couple of obvious things to check. If the =0A>en
gine runs smoothly at lower power settings and cuts out at higher power =0A
>settings I would strongly suspect a fuel flow restriction as first guess.
I =0A>suggest he does a fuel flow check to see if he is getting enough flo
w. Next =0A>check that there are no air leaks caused by carb mount failure
/pipes =0A>adrift/blocked. Check both carbs are opening together/ no probl
ems with =0A>throttle cables.=0A=0AIt could be ignition and changing the pl
ugs and fuel at least eliminates some =0Athings but it is unlikely that a s
hort period on Avgas would cause plug failure.=0A=0AResponse . . .=0AWe are
convinced the problem is fuel or rather lack of however, we did fuel flow
=0Atests the result of which was 10 litres over a 4 minute period on each o
f the =0Atwo fuel pumps. This equates to 150 LPH which is more than enough
for the 914. =0AInspection of the gascolator and another filter revealed
they were as clean as a =0Awhistle.=0A=0AThere were no visible signs of any
fuel leaks around the float bowls, carb =0Amounts all appeared normal as d
id everything else we checked by looking and =0Afeeling. Both carbs opened
very smoothly and in unison. Both throttle valves =0Asimultaneously conta
ct idle stops and in turn, the full throttle stops. There =0Awas absolutel
y no sign of any sticking throttle cables.=0A=0AWe replaced the fuel and fi
tted new spark plugs only because we were advised to =0Ado so by the Rotax
agent. We were not convinced it would have any effect (and =0Ait didn't) b
ut we did as advised because we thought we had nothing to lose. We =0Anow
have a spare set of spark plugs as a result of the exercise.=0A=0AJIM BROWN
. . . . .=0A> Try this. turn off the turbo with the Isolation switch....Do
a run up, if you =0A>get full power, and no missing, without the turbo, th
en leave the turbo out of =0A>the circuit and fly home....=0AThe fuel regul
ator on top of the airbox is bad. As the engine RPM is going to =0Afull po
wer, at about 4400 RPM the missing starts.,the fuel regulator on top of =0A
the airbox, is supposed to shut off the return fuel, so that all fuel is
=0Aavaiable for the turbo. In other words the engine is starving for fuel u
nder =0Aboost. The engine will run just fine as a non-turbo.....=0A=0ARespo
nse . . . . .=0ATurning the turbo isolation switch off was one thing we had
n't thought to try =0AJim so when Tony relayed your message, I had high hop
es it would be the answer =0Ato a maiden's prayer. Alas, it had no effect
so you can imagine my =0Adisappointment. I am however convinced the proble
m IS the fuel pressure =0Aregulator Jim but not having the equipment to do
any tests and with very limited =0Atools available, we were unable to check
it. The fact that the regulator is =0Acommon to both carbs indicates to m
e a logical reason why the engine completely =0Acut like it did on 3 occasi
ons. On one occasion when the throttle was left =0Aopen, the engine all bu
t stopped before it fired up again. This aircraft had not =0Abeen flown for
2 years and I suspect the diaphragm may have dried out and become =0Aporou
s or some dried out fuel residue may be in some orifice or something else
=0Ajust as sinister. I may be talking crap here because I have not yet see
n the =0Ainside of a 914 regulator.=0ANow that I have read your full postin
g, with hindsight and as a result of the =0Asteep learning curve I have bee
n on regarding the 914, maybe if I had clamped =0Aoff the fuel return line
somewhat, we may have at least seen some change in the =0Arunning to confir
m we might be on the right track.=0A=0AKEVIN KLINEFELTER . . . .=0A> You ca
n check the operation of the turbo wastegate on the ground. Observe the =0A
>wastegate arm move through it's test cycle when the master is turned on, t
o see =0A>if it is sticking.=0ASounds like carburators to me. He can inspec
t and clean the float bowls without =0Aremoving the carbs from the engine (
19 mm bolt on the bottom of the bowls, =0Atorque to 5.5nm). Also make sure
that the carbs are balanced=0A=0AResponse . . . .=0AWastegate works perfe
ctly on turn on thanks Kevin. Have repeatedly observed it =0Acycle as you
suggested. Because of the sophiscated fuel drain trays under the =0Acarbs,
we were unable to remove the float bowls and didn't have sufficient tools
=0Ato go any further. However, a few weeks before we picked up the aircr
aft, a =0Ayearly inspection was carried out during which the carbs were bot
h removed, =0Achecked and some gaskets replaced. The carbs were also balan
ced. The complete =0Acutting of the engine we experienced leads me to beli
eve it would not be the =0Acarbs because I cannot see two carbs failing sim
ultaneously except for lack of =0Afuel as aforementioned in my response to
Jim.=0A=0AWILLIAM DANIELL . . . .=0A> I use 100% AVGAS and in my experienc
e no it doesn't. Plugs last 50 hours no =0A>problem. I have never had a s
et of plugs foul up in nearly 7 years - I admit I =0A>change them every 25
hours.=0AI have this sort of issue after an overhaul and it had to do with
two things. =0APart of the problem was one of the tubes from the airbox t
he carb had come loose =0Aand unbalanced the carbs=0ASecondly the mating be
tween the turbo and the engine was "out" - which meant =0Athat the turbo wa
s providing too much or too little boost relative to the power =0Asetting.
We tested the system by making the wastegate "manual" with=0Aa vernier ca
ble.=0A=0AResponse . . . .=0AI agree with you about the AVGAS William. The
plugs in this engine had only =0Adone 3.5 hrs at the time so it would need
to be special Avgas to stuff them in =0Athat amount of time. On inspectio
n, the plugs showed signs of running a bit =0Alean if anything which would
be consistent with the rough running at higher =0Apower settings I would th
ink. There was no sign of lead in them and during the =0A4 hour return tri
p by car to purchase new plugs, we had the removed plugs tested =0Aon a plu
g tester. All were Ok. I have not yet had the chance to check the =0Aothe
r items you mention William so am unable to comment on those yet but they
=0Awill be checked at a later stage thanks.=0A=0APAUL McALLISTER . . . .=0A
> If Kingsley's airplane only has a couple of hours on it then I'd be looki
ng at =0A>the fuel filters. I pulled an unbelievable amount of crap out of
the filters =0A>for the first 50 hours and I was very careful (or so I tho
ught) to make sure =0A>that fuel system was clean before my first flight.
=0A=0AResponse . . . . .=0AThis aircraft has done 330 hours Paul but nothin
g for 2 years. As mentioned =0Aearlier, we did check the filters to no ava
il and a fuel flow check proved =0Asatisfactory. When I finally get to fly
ing my own aircraft Paul, rest assured =0Ayour suggestion will be strictly
followed.=0A=0AThank you again one and all for your contributions. Many he
ads are certainly =0Abetter than a couple as bereft of 914 knowledge as our
s were at the time. I =0Awill advise the outcome in due course.=0A=0ABest
=
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