You bet.
Bud
----- Original Message -----
From: GRAHAM SINGLETON<mailto:grahamsingleton@btinternet.com>
To: europa-list@matronics.com<mailto:europa-list@matronics.com>
Sent: Friday, April 15, 2011 4:17 AM
Subject: Re: Europa-List: Re: JABIRU 3300 BRAND NEW OVER TEMPERATURE
DURING TAXI
-------------------------------------------------------------------------
-----
From: Bud Yerly <budyerly@msn.com<mailto:budyerly@msn.com>>
To: europa-list@matronics.com<mailto:europa-list@matronics.com>
Sent: Friday, 15 April, 2011 1:18:37
Subject: Re: Europa-List: Re: JABIRU 3300 BRAND NEW OVER TEMPERATURE
DURING TAXI
Hi Bud
I think the uneven mixture is a serious issue with the Jab6. If the
inlet to the carb is curved the airspeed in the venturi will not be
equal across the whole area so the spray of droplets will be uneven too.
To a certain extent the same thing happens with Rotax so the front
cylinders get more fuel than the rear at some throttle settings, drops
of fuel don't turn corners the same as air molecules!
Both engines need fuel injection imho. Or a redesign of the induction
system to get the fuel/air mixture properly dispersed before any
splitting
Graham
The engine at cruise will die if the carb heat is pulled and then the
throttle retarded so we have a carburation issue still. It is just too
lean it seems. Many things may be at play. We'll investigate one at a
time.
Shock cooling is a pain so the inlet has a dam on the front cylinders
to help out, but it bears watching. We lazy Rotax people normally don't
have to go to the cooling page of the EIS as part of our descent check,
so make it part of your crosscheck.
To our friend in Argentina:
Thanks to Johns Lawton's and the Jabiru crowd's research, the mixture
per cylinder has been identified as a problem in some of the stock
engines. The induction system we found is prone to small leaks which
leans the cylinders and causes high EGT and CHT. We are pulling the
carb (again) to take out the owner installed lean kit. The smooth bore
inlet to the carb is a good idea, but please ensure the hose clamps and
rubber and gasket parts in the induction are sealing well. Also, the
induction hose must be able to hold its shape and still be flexible
enough to take engine movement. If that tube collapses your engine
dies. My experience has been if your cylinders are running hot and the
EGT is high, fix the induction, by either fixing air leaks, jetting the
carb differently or moving the mixture clip or both. I have not tried
rotating the carb off axis.
Bud Yerly
Still recovering from Sun 'n Fun.
----- Original Message -----
From: AirEupora<mailto:AirEupora@sbcglobal.net>
To: europa-list@matronics.com<mailto:europa-list@matronics.com>
Sent: Tuesday, April 12, 2011 10:05 AM
Subject: Europa-List: Re: JABIRU 3300 BRAND NEW OVER TEMPERATURE
DURING TAXI
<AirEupora@sbcglobal.net<mailto:AirEupora@sbcglobal.net>>
I can not address this problem as I have not run my engine, but I
was told by Jim McCormick to build a square box in front of the
carburetor. I'll include a couple of pictures.
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=336709#336709<http://forums
.matronics.com/viewtopic.php?p=336709#336709>
Attachments:
http://fp; Features Chat,
<http://forums.matronics.com//files/carb_box_021_853.jpg>http://www.matro
nnbsp; via the Web title=http://forums.matronics.com/
href="http://forums.matronics.com";>http://forums.matronics.com<http://w
ww.matronics.com/Navigator?Europa-List>
_p; generous bsp;
title=http://www.matronics.com/contribution<http://www.matronics.com/co
ntribution>
href="http://www.matronics.com/contribution";>http://www.matronics.com/c
=======<http://www.matronics.com/contribution%22%3Ehttp://w
ww.matronics.com/c=======>=========
http://www.matro===================
http://www.matronics.com/Navigator?Europa-List<http://www.matronics.com/N
avigator?Europa-List>
http://www.matronics.com/contribution<http://www.matronics.com/contributi
on>
|
