=0A=0A=0A=0A=0A________________________________=0AFrom: Bud Yerly <budyerly
@msn.com>=0ATo: europa-list@matronics.com=0ASent: Friday, 15 April, 2011 1:
18:37=0ASubject: Re: Europa-List: Re: JABIRU 3300 BRAND NEW OVER TEMPERATUR
E DURING TAXI=0AHi Bud=0AI think the uneven mixture is a serious issue with
the Jab6. If the inlet to the =0Acarb is curved the airspeed in the ventur
i will not be equal across the whole =0Aarea so the spray of droplets will
be uneven too. To a certain extent the same =0Athing happens with Rotax so
the front cylinders get more fuel than the rear at =0Asome throttle setting
s, drops of fuel don't turn corners the same as air =0Amolecules!=0ABoth en
gines need fuel injection imho. Or a redesign of the induction system to
=0Aget the fuel/air mixture properly dispersed before any splitting=0AGraha
m =0A=0A=0AThe engine at cruise will die if the carb heat is pulled and the
n the throttle =0Aretarded so we have a carburation issue still. It is ju
st too lean it seems. =0AMany things may be at play. We'll investigate o
ne at a time.=0A =0AShock cooling is a pain so the inlet has a dam on the
front cylinders to help =0Aout, but it bears watching. We lazy Rotax peop
le normally don't have to go to =0Athe cooling page of the EIS as part of
our descent check, so make it part of =0Ayour crosscheck.=0A =0ATo our fri
end in Argentina:=0AThanks to Johns Lawton's and the Jabiru crowd's researc
h, the mixture per =0Acylinder has been identified as a problem in some of
the stock engines. The =0Ainduction system we found is prone to small le
aks which leans the cylinders and =0Acauses high EGT and CHT. We are pull
ing the carb (again) to take out the owner =0Ainstalled lean kit. The smo
oth bore inlet to the carb is a good idea, but =0Aplease ensure the hose c
lamps and rubber and gasket parts in the induction are =0Asealing well. A
lso, the induction hose must be able to hold its shape and =0Astill be fle
xible enough to take engine movement. If that tube collapses your =0Aengi
ne dies. My experience has been if your cylinders are running hot and the
=0AEGT is high, fix the induction, by either fixing air leaks, jetting th
e carb =0Adifferently or moving the mixture clip or both. I have not trie
d rotating the =0Acarb off axis.=0A =0A=0ABud Yerly=0AStill recovering from
Sun 'n Fun.=0A----- Original Message ----- =0A>From: AirEupora =0A>To: eur
opa-list@matronics.com =0A>Sent: Tuesday, April 12, 2011 10:05 AM=0A>Sub
ject: Europa-List: Re: JABIRU 3300 BRAND NEW OVER TEMPERATURE DURING TAX
l.net>=0A>=0A>I can not address this problem as I have not run my engine
, but I was told by =0A>Jim McCormick to build a square box in front of
the carburetor. I'll include =0A>a couple of pictures.=0A>=0A>=0A>=0A>
=0A>Read this topic online here:=0A>=0A>http://forums.matronics.com/view
topic.php?p=336709#336709=0A>=0A>=0A>=0A>=0A>Attachments: =0A>=0A>http://
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>http://forums.matronics.com=0A>_p; generous bsp;
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