William and all Rotax / Jabiru owners:
At Custom Flight we are having the same problem with the new carb kits.
Jim Glover had his plane in for major repairs and upgrades. The engine
sat a while (six months) and we refurbished the carbs with new
everything for Jim since the carbs had 300 hours on them. We have done
this numerous times without distress or difficult tuning. The engine at
altitude began missing. At low boost below 27 inches or low manifold
pressures under boost, the engine ran great, but when the boost came up
to 34 inches, going through 6000 ft., the engine went out of tune. We
couldn't fix it so we had Jim fly down to Lockwood to have them have a
go at it. They couldn't fix it either after new carb bowls, complete
teardown and rebuild again. In desperation, Lockwood put two new carbs
on the engine, tuned it up and it is back to normal at great cost and
time for the mechanics and owner.
Now suddenly we are having a rash of 914 turbo leaks around the floats.
N419PL and 12AY have had leaks as have Bob, William and others. A
turbocharged engine must have proper seals on the bowls and compensator
for sure to operate properly. Take this as some hard learned advice::
First, do not overtorque the float bowls to seal a leak on the 914, as
the bowls bend and distort and they are $140 each.
Second, Bing has recommended cork gaskets for the float bowl for all the
912/912S engines with the bail clips. This is not sold as part of the
tune-up kit (normally sold for about $50 with all the O-rings and paper
gaskets for two carbs). You have to ask for the cork gaskets
specifically. A Bing Tech at the factory told us that we should be
using the cork on all the bail clip Bing carbs. Jabiru included. On
the 914 they still recommend the paper gasket. We are not in agreement
with Bing on the 914.
We are surprised that it seems that the paper gaskets are just not
holding up in the 914, especially if it sits a while. So we are putting
in cork gaskets now as a matter of course on the 914s to see how that
works. Of course the cork gaskets cost twice as much, but between Kerry
at Lockwood, Ed and I we are looking at the cork to solve this issue
long term for leaky bowls.....
Regards,
Bud Yerly
Europa Tech Support.
----- Original Message -----
From: William Daniell<mailto:wdaniell@etb.net.co>
To: europa-list@matronics.com<mailto:europa-list@matronics.com>
Sent: Tuesday, May 22, 2012 8:41 AM
Subject: Europa-List: for interest - float bowl gaskets
<wdaniell@etb.net.co<mailto:wdaniell@etb.net.co>>
For the record an interesting thing happened to me with my zenith
which has
an aftermarket turbo fitted.
Above 11k full power caused vibration - I thought this was just a
normal
"fault" of the aftermarket turbo. Take off from 8500 etc all normal.
However the problem got worse and manifested itself at lower
altitudes.
We put on a vernier to manually adjust waste-gate and the problem
showed up
at higher MP - over 34". Otherwise the engine ran normally. It felt
like
fuel starvation.
New carb vacuum chamber diaphragms, carb balance, full fuel system
check,
fuel pressure - no change. All readings completely normal except for
the
vibration and minor power loss at higher altitudes and power settings.
Just out of interest we changed the carb float bowl gaskets which had
been
changed recently using rotax original parts. We put in after market
softer
cork gaskets because that's what we had. This cured the problem
completely.
The conclusion was that the float bowls had been dropped or the mating
faces
had been damaged in some very minor way allowing air to get into the
system
but only at higher differential pressure - higher power settings and
higher
altitude. There was no evidence of fuel leak. The softer aftermarket
gasket compensated for the minor flaws in the mating surfaces of the
float
bowls.
We spent two days and maybe USD500 solving a problem which was turned
out to
be a 5c gasket.
Will
Bogota
-----Original Message-----
From:
owner-europa-list-server@matronics.com<mailto:owner-europa-list-server@ma
tronics.com>
[mailto:owner-europa-list-server@matronics.com] On Behalf Of europapa
Sent: 21 May, 2012 15:51
To: europa-list@matronics.com<mailto:europa-list@matronics.com>
Subject: Europa-List: Re: Lack of power with water heated carb body
mountings
<experimental@online.de<mailto:experimental@online.de>>
Hi,
in the mailing list I can see all of your replies but not here in the
forum
[Question] .
I am very happy to see so many help by real experts.
Thank you so much.
Karl, Craig, Bob, Pete,Terry, John and all the others, thank you so
much.
I am now thinking too that the added heat is not an issue.
Today I had my prof-check or how do you call it?
At full throttle and even with my not so light flight inspector the
power
produced by my 912s at high rpm / full throttle was good.
But when reducing the rpm / throttle the engine became rough like an
old
diesel engine.
I am rather confused.
Now I have removed the carbs and will overhaul them.
If that will not bee the answer I will totally remove the carb heaters
to
see if that will solve the problem.
If there will still no cure ......... dose anybody wants to buy a very
nice
Europa Trigear...... ( no way! ;-) ).
More information later, I am really tiered after this long and
exciting day.
CU
Juergen
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