FOR IMMEDIATE RELEASE
Jaba
Chat Abril 2002
Contenido:
Introducción
Novedades del motor de 8 cilindros
Festival aereo de Narromine
Motores Jabiru
J400 Demo
Introduction
Welcome
to another edition of Jaba Chat. Happy Easter to you all we hope you had a well
earned rest and enjoyed yourselves what ever you did over the 4 days break.
We've got lots of exciting news concerning a few of our staff members, Airshows
and lots more.
Natfly Narromine 2002 Fly In was on over the Easter break with a crew of Jabiru
members attending again this year. So read on to find out what is going on with
Jabiru.
8 CYLINDER ENGINE UPDATE
The 8 cylinder engine is currently
in our workshop for its second inspection. The process we follow is very similar
to when an engine is overhauled, the engine is fully stripped down and the
crankshaft & conrod are sent away for crack testing. All remaining parts are
inspected and measured checking for wear, then modifications are made where
necessary.
We are pleased to say that it has all checked out well and only a few cosmetic
changes are required. As we are using a lot of proven parts from the 2200 and
3300 engines it has been a fairly trouble free run.
The way the 8 cylinder is progressing we are hoping to be able to release it for
sale in the later part of this year. We will have more updates in each issue of
this Newsletter just to keep you informed.
Narromine
Airshow
Well
it was on again the Natfly Narromine 2002, like a good wine it is improving with
age as we begin the story of another successful airshow for Jabiru.
Myself, Phil, Ian Bent, Debbie, Sonya, Don, Doug, Mike and Alan from Camit all
made the trip in our Jabiru's. Debbie, Sonya and Laila ( Debbie's Daughter) were
my passengers.
I must start by personally thanking all staff members who attended the airshow,
their assistance is very much needed and appreciated over the Easter long
weekend.
We encountered a few storms on the fist leg of our journey which opened up
Sonya's eyes a bid as she saw lightening strikes coming from no where. We
stopped at Goondaawindi to let the storm pass and then eventually got on our way
again and arrived at Narromine in the early evening.
The bad weather on Thursday and Friday delayed some arrivals, but by mid
Suturday the turnaout of Jabiru's quickly filled the paddock once again.
There was huge interest in our new J200 & J400 kit model - you had to be
quick to catch them on the ground, as the demo flights were continuous all the
weekend. It was a great way for peoples to trust in this aircraft's capability
as they got to see it fly with 4 passengers.
Engine interest was sparked as a result of our "J" Models being
powered by the 6 cylinder engine, people were amazed at its performance as its
performance as it powered along with 4 peoples on board.
Natfly always provides us with the opportunity to show our fellow Australian
customers how strong we are in the Ultralight and General Aviation market. Our
mission is to develop and enhance affordable flying, not only in Australia, but
also around the world.
Phil and I would also like to thank all our Jabiru Customers for their continual
support at Narromine each year, your presence is very much appreciated.
2002 is looking good with may more Airshows to come - So see you all there!
Happy Flying
Rod.
JABIRU ENGINES
New Engines
Engine manuals give points and tips for early engines operation. The first 25
hour shuld be run using a "straight Oil" that is one that will promote
"Bed in" of the engine. The first few hours should be carefully done
with due care to a number of points ( see section 4.7 in Instruction and
Maintenance Manual). Even though the engine has been given a "run in"
sequence and ready for flight, the process is an ongoing one. Engine revs and
power should be varied with special attention to CHT and Oil temperatures. The
CHT drops noticeably as the engine frees up. Avoid long steep full power climbs,
climb out at a slightly higher speed than normal. Circuit work is a good way of
enhancing "bed in" engine components. Aircraft engine are required to
perform at continual high power setting for substantial periods of time. Early
use is therefore most important to ensure a long trouble free life.
Care should also be afforded to oil temp and pressure. Engine must use an oil
cooler. Oil should operate between 70 - 90°C for best results. At low
temperatures contaminates are not evaporated from oil satisfactorily. Cold oil
is harder to reach wearing parts on initial start up, so use of multigrade in
winter is a good idea. Turning the prop a number of times before start up is
also worth considering. Possibly one of the most important factors to a new
engines performance is the installation. If installed in a Jabiru it is all
straight forward. In various other aircraft carefull consideration must be made
to many areas especially cooling.
Head Torquing and Valve Clearance.
As the engine uses "solid lifters" periodic adjustments is necessary.
We do find at times the result of poorly adjusted valves when overhauling
engines. The opposite also applies on engines of high times (1000 hours) that
have been subjected to correct maintenance and operational procedures. In these
cases valves show no stem of face wear. Now for some "technical bits".
The exhaust valve face to seat contact is responsible for up to 75% of all heat
transfer. When poorly adjusted valves accumulate combustion deposits on the
valve face, poor sealing results and the condition wil only deteriorate.
This only gets worse to the point of perhaps a riding valve. Temperatures
therefore sky rocket in this area causing valve face distortion and further bad
sealing, abnormally high temperatures, ay least severe valve face distortion and
eventual failure of the valve. Exhaust temperatures are normally around 1600 -
2000°F. With poor valve sealing and clearance this temperature greatly
elevates. The end result can be valve failure and disintegration and forced
landing. It is therefore vital that early adjustment/checking is undertaken on a
new engine until the engine "settles in " and at each 50 hourly
inspection. If an exhaust valve exhibits poor sealing it is best removed and
corrected.
With the later engines 1000 hours are easily attained, maintained and operated
correctly. The valves used are of top quality and usually show very little wear.
Engine Jotting
Engine reliability has always been one of our ever present and ongoing goals.
Engines are now firmly established. At 1000 hours only minor work is usually
required however the mandatory overhaul is undertaken. A number of changes have
occurred to promote more reliability and power. The 2200 engine now currently
runs around 84 hp at 3300 rpm, while the 6 cylinder averages an output of around
127 hp at 3300 rpm. While output has increased no compromise has been made to
reliability or structural integrity.
Maintenance
Last Jaba Chat the "gremlins" gave our maintenance person Greg Jack in
Healsville Victoria slightly altered phone numbers, correction is as follows:
Home: 03 5962 5776
Mobile: 041 1 212 237
As noted earlier regular
maintenance especially with valve setting, head tensioning and correct oil is
important. Some flying schools change oil every 25 hours. When overhauling, the
internal condition of engine usually reflects this. Usual service every 50 hours
require oil and filter change. Remember a 50 hour contains many items to check
with both engine and airframe. Service notes are always available though the
engine shop. The Jabiru Technical Manual outlines the full inspection notes.
RPM
Probably the most talked about problem is "my engine won't rev out of
perform correctly". In the vast majority of cases the problem exist with
incorrect tacho readings. Tacho's now sence on 2 tags behind the flywheel fear
teeth. Simply using another tacho to cross reference and calibrate usually cures
the problem of wrong indications. Tachos using the 2 tag system are set up in
the factory before dispatch and are "spot on". There are many other
areas that can affect RPM howeverthe next one is usually a different prop.
6 Cylinder Ignition Coils
It can happen that the pilots side ignition coil can become quite hot to the
point of miss-firing, so a cure is to attach a small tube approximately 10 mm
diameter from the end of the air duct and guided down to the coil. This small
amount of air is all that's needed to keep the coil cooler and functioning. This
depends on installation and cooling heat range within the cowl. Four cylinder
engines have never exhibited this situation.
Cooling
A point often overlooked is that the majority of engine cooling is obtained
through the oil. Good cooler installation is therefore most important. Cylinder
head cooling also plays a part in this equation. Cowling design uses incoming
and exiting air to promote good cooling. Gaps in the cowl cooler elements wastes
good air, ensure area uses all the incoming air effectively.
Hard Luck Stories
There have been a number of engine problems caused by loose oil hoses or
detachment of the oil hose from the cooler. If maintenance is undertaken in this
oil area, or an engine change occurs a double check before cowling up may be in
order. Clamps should not be over tightened to squash hoses nor should they be
loose enough for minimum clamping action which will allow oil overload when
under pressure. A check should be made of fire sleeve condition and the lay of
the hoses on the bottom cowl with reference to the muffler and exhaust pipes
before attaching the top cowl. Usually a good idea to run the engine and inspect
all areas before cowling up and flying.
If you push the stick forward the hoses get bigger
If you pull
the stick back they get smaller
If you keep pulling the stick back, then they get bigger
again.
Take off are optional, landing are
mandatory!
Cheers for now,
Don Richter
J400 DEMONSTRATION
FLIGHTS FOR NEW & EXISTING CUSTOMERS
We now have a J400 Factory
Demonstrator which we have been using for Demo flights so that customers can see
how the new model performs. If you would like a demo flight in the new J400 fell
free to call in and see us here at the Jabiru factory and we can organize one
for you. Factory tours are also available to visitors to the Bundaberg area,
call in to see us at Airport Drive, Hinkler Airport, Bundaberg Queensland and
one of the staff will be more than happy to show you around.
For More Information Contact:
Jabiru Chile
Via Naranja 4230 Vitacura
Tel: 56-9-826 5210
FAX: 56-2-219 2115
Internet: info@jabiru.cl
Send mail
to christian.tannen@jabiru.cl
with questions or comments about this web site.
Copyright © 2002 Jabiru Chile
Last modified: May 26, 2002
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