Today's Message Index:
----------------------
1. 03:01 AM - Re: Re: Icom A24 and Jabiru 2200A compatabiltiy issue (Wayne Flowers)
2. 09:13 AM - Re: Icom A24 and Jabiru 2200A compatabiltiy issue (DanM)
3. 02:56 PM - Re: Engine Shut Down (FLYaDIVE)
4. 03:12 PM - Re: Engine Shut Down (zeprep251@aol.com)
5. 04:25 PM - Re: Engine Shut Down (zeprep251@aol.com)
6. 07:42 PM - Re: Engine Shut Down (Martin Hone)
7. 08:04 PM - Re: Engine Shut Down (BobsV35B@aol.com)
8. 09:46 PM - Re: Engine Shut Down (Martin Hone)
Message 1
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| Subject: | Re: Icom A24 and Jabiru 2200A compatabiltiy issue |
Radio Shack has them
----- Original Message -----
From: "Tex Mantell" <wb2ssj@frontiernet.net>
Sent: Friday, November 19, 2010 7:19 PM
Subject: Re: JabiruEngine-List: Re: Icom A24 and Jabiru 2200A compatabiltiy
issue
> <wb2ssj@frontiernet.net>
>
> Dan,
> Where did you purchase the chokes? I would like to try them. Tex
>
>
> ----- Original Message -----
> From: "DanM" <danm@powerdesignelectric.com>
> To: <jabiruengine-list@matronics.com>
> Sent: Thursday, November 18, 2010 11:45 AM
> Subject: JabiruEngine-List: Re: Icom A24 and Jabiru 2200A compatabiltiy
> issue
>
>
>> <danm@powerdesignelectric.com>
>>
>> Seems putting a choke on each mag to distributor wire did the trick
>>
>> --------
>> Dan Mc Intyre
>> Kitfox IV
>> Jabiru 2200 SN 1311 , 51 hours
>> Sensenich 62x46
>> N443DM
>>
>>
>>
>>
>> Read this topic online here:
>>
>> http://forums.matronics.com/viewtopic.php?p=319928#319928
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>> -----
>> No virus found in this message.
>> Checked by AVG - www.avg.com
>>
>
>
>
Message 2
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| Subject: | Re: Icom A24 and Jabiru 2200A compatabiltiy issue |
Tex, here's a link to where you can buy them. I didn't purchase mine I took them
off electrical chargers that I had laying around. I do plan on buying some
new though.
http://www.tdk.com/distributor.php
--------
Dan Mc Intyre
Kitfox IV
Jabiru 2200 SN 1311 , 51 hours
Sensenich 62x46
N443DM
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=320180#320180
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| Subject: | Re: Engine Shut Down |
G.Aman:
You are misinformed.
1 - IF the cylinders did "run a couple hundred degrees higher cylinder head
temps and would run on with out spark ignition,"<-- Quoted from G.Amam. You
wound have a condition of PRE-IGNITION which would surely be there even a
few hundred degrees still hotter DURING NORMAL RUNNING. If
this occurred you surely would have a rough running engine. And quickly on
it way to the grave.
2 - When you make the statement: "General aviation engines run a couple
hundred degrees higher cylinder head temps", I am forced to think you
are comparing aviation to automotive. Auto engines generally run HOTTER
than aircraft engines...
Lets define a few things here. When you say hotter WHAT are you
measuring, CHT?
Well there are very few air cooled auto engines out there. Only one comes
to mind, the old VW. They were rear mounted, not a very good place for air
flow cooling. Yet, they ran very well. So well that they have been used in
aviation.
The newer engines of today run hotter than aviation engines for one
simple reason: They have higher compression ratios. Most aircraft engines
run 7:1, 7.5:1, 8:1. 8.5:1 and there are a few that are 9 & 10:1. Cars
start around 10:1 and go up to 12.5:1 for normal production cars. SO, how
do they stay cool running? They are liquid cooled. There are some aviation
engines that are co-cooled -liquid and air.
So, lets measure something else... EGT.
What is the limiting factor in leaning an engine? Nonuniform air-fuel flow
to all cylinders. I say Non Uniform because once you peak one cylinder you
stop there. (I am not going to get into LOP & ROP since we are talking
carborated engines.) And deforming of the metal. Oh, lets not forget
Pre-Ignition. Most engine savvy pilots will not go above 1450 F on EGT and
the normal range is usually 1200 to 1400 F. This is done for longevity of
the engine.
So maybe the question should be: Why CAN'T we shut down an aircraft engine
like a car?
Because car engines are not built like aircraft engines. When you shut down
a car engine you shut down all sorts of electrical things, Timing, Computer,
Fuel Pump, Air/Fuel Valves and of course the spark. Being that there is a
fuel pump and Air/Fuel Valves and most of todays cars are fuel injected... I
guess you could say you are shutting the car the same as 'most' a planes.
Loaded Question: If the flash point of gas is so low, below that of
internal CHT why do we not Pre-Ignition all the time?
Barry
On Fri, Nov 19, 2010 at 9:27 PM, <zeprep251@aol.com> wrote:
> Mike,
> If you have a mixture control on your carburetor you could shut it off that
> way.But if you want to kill it by turning off the fuel selector,be prepared
> to wait for a couple minutes for the fuel bowl on the Bing to run dry.
> General aviation engines run a couple hundred degrees higher cylinder head
> temps and would run on with out spark ignition,you had to starve it of fuel
> to kill it.
> G.Aman Jabiru 2200A 600 hrs
>
>
> -----Original Message-----
> From: MHerder <michaelherder@beckgroup.com>
> To: jabiruengine-list <jabiruengine-list@matronics.com>
> Sent: Thu, Nov 18, 2010 9:44 pm
> Subject: JabiruEngine-List: Engine Shut Down
>
>
>
> Manual on my 3300 says just turn the ignition off to shut it down... Any reason
>
>
> why we should or shouldn't be shutting it off buy shutting off the fuel?
>
>
> --------
>
>
> One Rivet at a Time!
>
>
> Read this topic online here:
>
>
> http://forums.matronics.com/viewtopic.php?p=319979#319979
>
>
> ==========
>
>
> _blank">www.aeroelectric.com
>
>
> " target="_blank">www.buildersbooks.com
>
>
> ="_blank">www.homebuilthelp.com
>
>
> _blank">http://www.matronics.com/contribution
>
>
> ==========
>
>
> ist" target="_blank">http://www.matronics.com/Navigator?JabiruEngine-List
>
>
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>
>
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>
>
> ==========
>
>
> *
>
>
Message 4
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| Subject: | Re: Engine Shut Down |
Martin,your right,I should said when the engine is hot
My Beech 35,although injected with a mixture/ fuel cut off had a red line c
yl head temp of 435F.My Jabiru runs well under 300f, red lined at 325.Mayb
e the difference between cast and machined billet heads limits the temps so
me.Should not have an issue with moving the prop and having it start accide
ntally ,takes about 300rpm to fire the solid state pickup coil.but the issu
e was shutting the Bing equipped engine down fuel wise.My Jabiru runs on 10
0LL as well.
Thanks G.A.
-----Original Message-----
From: Martin Hone <aerobiz1@gmail.com>
Sent: Fri, Nov 19, 2010 9:54 pm
Subject: Re: JabiruEngine-List: Engine Shut Down
Hi G.A.
I wouldn;t be too sure about that. I think you will find that the CHT's of
any well running Continental or Lycoming are pretty much the same as for a
well running Jab. That would be between 300 and 380 degrees F in my exper
ience. The reason these engines use idle mixture cut-off is
1. Because they can
2. A broken 'P' lead won't allow the engine to fire if the prop is moved
3. Highly leaded fuels provide more material that can glow in the combustio
n chamber and will keep the engine running-on even if the mags are switched
off.
Cheers
Martin
On Sat, Nov 20, 2010 at 12:27 PM, <zeprep251@aol.com> wrote:
Mike,
If you have a mixture control on your carburetor you could shut it off that
way.But if you want to kill it by turning off the fuel selector,be prepare
d to wait for a couple minutes for the fuel bowl on the Bing to run dry. Ge
neral aviation engines run a couple hundred degrees higher cylinder head te
mps and would run on with out spark ignition,you had to starve it of fuel t
o kill it.
G.Aman Jabiru 2200A 600 hrs
-----Original Message-----
From: MHerder <michaelherder@beckgroup.com>
Sent: Thu, Nov 18, 2010 9:44 pm
Subject: JabiruEngine-List: Engine Shut Down
.com>
Manual on my 3300 says just turn the ignition off to shut it down... Any r
eason
why we should or shouldn't be shutting it off buy shutting off the fuel?
--------
One Rivet at a Time!
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=319979#319979
_blank">www.aeroelectric.com
" target="_blank">www.buildersbooks.com
="_blank">www.homebuilthelp.com
_blank">http://www.matronics.com/contribution
ist" target="_blank">http://www.matronics.com/Navigator?JabiruEngine-List
tp://forums.matronics.com
_blank">www.aeroelectric.com
.com" target="_blank">www.buildersbooks.com
="_blank">www.homebuilthelp.com
_blank">http://www.matronics.com/contribution
ist" target="_blank">http://www.matronics.com/Navigator?JabiruEngine-List
tp://forums.matronics.com
Message 5
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| Subject: | Re: Engine Shut Down |
Barry
You are absolutely right.What could I have been thinking.
-----Original Message-----
From: FLYaDIVE <flyadive@gmail.com>
Sent: Sat, Nov 20, 2010 5:56 pm
Subject: Re: JabiruEngine-List: Engine Shut Down
G.Aman:
You are misinformed.
1 - IF the cylinders did "run a couple hundred degrees higher cylinder head
temps and would run on with out spark ignition,"<-- Quoted from G.Amam. Y
ou wound have a condition of PRE-IGNITION which would surely be there even
a few hundred degrees still hotter DURING NORMAL RUNNING. If this occurred
you surely would have a rough running engine. And quickly on it way to th
e grave.
2 - When you make the statement: "General aviation engines run a couple hun
dred degrees higher cylinder head temps", I am forced to think you are comp
aring aviation to automotive. Auto engines generally run HOTTER than aircr
aft engines...
Lets define a few things here. When you say hotter WHAT are you measuring,
CHT?
Well there are very few air cooled auto engines out there. Only one comes
to mind, the old VW. They were rear mounted, not a very good place for air
flow cooling. Yet, they ran very well. So well that they have been used
in aviation.
The newer engines of today run hotter than aviation engines for one simple
reason: They have higher compression ratios. Most aircraft engines run 7:
1, 7.5:1, 8:1. 8.5:1 and there are a few that are 9 & 10:1. Cars start aro
und 10:1 and go up to 12.5:1 for normal production cars. SO, how do they s
tay cool running? They are liquid cooled. There are some aviation engines
that are co-cooled -liquid and air.
So, lets measure something else... EGT.
What is the limiting factor in leaning an engine? Nonuniform air-fuel flow
to all cylinders. I say Non Uniform because once you peak one cylinder you
stop there. (I am not going to get into LOP & ROP since we are talking car
borated engines.) And deforming of the metal. Oh, lets not forget Pre-Ign
ition. Most engine savvy pilots will not go above 1450 F on EGT and the no
rmal range is usually 1200 to 1400 F. This is done for longevity of the en
gine.
So maybe the question should be: Why CAN'T we shut down an aircraft engine
like a car?
Because car engines are not built like aircraft engines. When you shut dow
n a car engine you shut down all sorts of electrical things, Timing, Comput
er, Fuel Pump, Air/Fuel Valves and of course the spark. Being that there is
a fuel pump and Air/Fuel Valves and most of todays cars are fuel injected.
.. I guess you could say you are shutting the car the same as 'most' a plan
es.
Loaded Question: If the flash point of gas is so low, below that of intern
al CHT why do we not Pre-Ignition all the time?
Barry
On Fri, Nov 19, 2010 at 9:27 PM, <zeprep251@aol.com> wrote:
Mike,
If you have a mixture control on your carburetor you could shut it off that
way.But if you want to kill it by turning off the fuel selector,be prepare
d to wait for a couple minutes for the fuel bowl on the Bing to run dry. Ge
neral aviation engines run a couple hundred degrees higher cylinder head te
mps and would run on with out spark ignition,you had to starve it of fuel t
o kill it.
G.Aman Jabiru 2200A 600 hrs
-----Original Message-----
From: MHerder <michaelherder@beckgroup.com>
Sent: Thu, Nov 18, 2010 9:44 pm
Subject: JabiruEngine-List: Engine Shut Down
.com>
Manual on my 3300 says just turn the ignition off to shut it down... Any r
eason
why we should or shouldn't be shutting it off buy shutting off the fuel?
--------
One Rivet at a Time!
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=319979#319979
_blank">www.aeroelectric.com
" target="_blank">www.buildersbooks.com
="_blank">www.homebuilthelp.com
_blank">http://www.matronics.com/contribution
ist" target="_blank">http://www.matronics.com/Navigator?JabiruEngine-List
tp://forums.matronics.com
_blank">www.aeroelectric.com
.com" target="_blank">www.buildersbooks.com
="_blank">www.homebuilthelp.com
_blank">http://www.matronics.com/contribution
ist" target="_blank">http://www.matronics.com/Navigator?JabiruEngine-List
tp://forums.matronics.com
Message 6
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| Subject: | Re: Engine Shut Down |
Hi again G.A.
Re shutdown :
It is not so much the temperature of the cylinder head, but more the glowing
embers of carbon or even a spark plug that will keep an engine running -
albeit roughly - when you turn the ignition off. That's why we use the lean
cut-off on traditional aircraft engines. Starve the critter.....
At other times :
On a Jabiru, with its need to spin fast to get the ignition to fire, you
would not expect a broken earth lead - making the ignition always hot - to
be so much of a danger than it would be on a Lycoming with its
impulse-coupled magneto.
Pull through one blade, as slow as you lie, and you can easily fire the
engine up.
So there is a few techniques to shutting your engine down. If you don't
have a mixture cut-off like you would with a Rotec TBI or Aerocarb or
regular Lycoming type carb or fuel injection system, you can simply turn the
ignition off and hope that there are no glowing embers in a combustion
chamber, (if there is, push the throttle full open - often the technique
used on Gypsy Majors in Austers and Tiger Moths) or you can turn the fuel
valve off and wait for the Bing float bowl to empty.
Realistically, just turn the ignition off.....
Martin
On Sun, Nov 21, 2010 at 9:09 AM, <zeprep251@aol.com> wrote:
> Martin,your right,I should said when the engine is hot
> My Beech 35,although injected with a mixture/ fuel cut off had a red line
> cyl head temp of 435F.My Jabiru runs well under 300f, red lined at
> 325.Maybe the difference between cast and machined billet heads limits the
> temps some.Should not have an issue with moving the prop and having it start
> accidentally ,takes about 300rpm to fire the solid state pickup coil.but the
> issue was shutting the Bing equipped engine down fuel wise.My Jabiru runs on
> 100LL as well.
> Thanks G.A.
>
>
> -----Original Message-----
> From: Martin Hone <aerobiz1@gmail.com>
> To: jabiruengine-list <jabiruengine-list@matronics.com>
> Sent: Fri, Nov 19, 2010 9:54 pm
> Subject: Re: JabiruEngine-List: Engine Shut Down
>
> Hi G.A.
>
> I wouldn;t be too sure about that. I think you will find that the CHT's
> of any well running Continental or Lycoming are pretty much the same as for
> a well running Jab. That would be between 300 and 380 degrees F in my
> experience. The reason these engines use idle mixture cut-off is
> 1. Because they can
> 2. A broken 'P' lead won't allow the engine to fire if the prop is moved
> 3. Highly leaded fuels provide more material that can glow in the
> combustion chamber and will keep the engine running-on even if the mags are
> switched off.
>
> Cheers
>
> Martin
>
>
> On Sat, Nov 20, 2010 at 12:27 PM, <zeprep251@aol.com> wrote:
>
>> Mike,
>> If you have a mixture control on your carburetor you could shut it off
>> that way.But if you want to kill it by turning off the fuel selector,be
>> prepared to wait for a couple minutes for the fuel bowl on the Bing to run
>> dry. General aviation engines run a couple hundred degrees higher cylinder
>> head temps and would run on with out spark ignition,you had to starve it of
>> fuel to kill it.
>> G.Aman Jabiru 2200A 600 hrs
>>
>>
>>
>>
>> -----Original Message-----
>> From: MHerder <michaelherder@beckgroup.com>
>> To: jabiruengine-list <jabiruengine-list@matronics.com>
>> Sent: Thu, Nov 18, 2010 9:44 pm
>> Subject: JabiruEngine-List: Engine Shut Down
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>> Manual on my 3300 says just turn the ignition off to shut it down... Any reason
>>
>>
>>
>>
>>
>>
>> why we should or shouldn't be shutting it off buy shutting off the fuel?
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>> --------
>>
>>
>>
>>
>>
>>
>> One Rivet at a Time!
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>> Read this topic online here:
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>> http://forums.matronics.com/viewtopic.php?p=319979#319979
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>> ==========
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>> _blank">www.aeroelectric.com
>>
>>
>>
>>
>>
>>
>> " target="_blank">www.buildersbooks.com
>>
>>
>>
>>
>>
>>
>> ="_blank">www.homebuilthelp.com
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>> _blank">http://www.matronics.com/contribution
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>> ==========
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>> ist" target="_blank">http://www.matronics.com/Navigator?JabiruEngine-List
>>
>>
>>
>>
>>
>>
>>
>>
>> ==========
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>> tp://forums.matronics.com
>>
>>
>>
>>
>>
>>
>>
>>
>> ==========
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>> *
>>
>>
>>
>>
>> _blank">www.aeroelectric.com
>>
>>
>> .com" target="_blank">www.buildersbooks.com
>>
>>
>> ="_blank">www.homebuilthelp.com
>>
>>
>> _blank">http://www.matronics.com/contribution
>>
>>
>> ist" target="_blank">http://www.matronics.com/Navigator?JabiruEngine-List
>>
>>
>> tp://forums.matronics.com
>>
>> *
>>
>>
> *
>
>
> ==========
>
>
> ic.com">www.aeroelectric.com
>
>
> .buildersbooks.com">www.buildersbooks.com
>
> help.com">www.homebuilthelp.com
>
>
> bution">http://www.matronics.com/contribution
>
>
> ==========
>
>
> tor?JabiruEngine-List">http://www.matronics.com/Navigator?JabiruEngine-List
>
>
> ==========
>
>
> tp://forums.matronics.com
>
>
> ==========
>
> *
>
> *
>
>
Message 7
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| Subject: | Re: Engine Shut Down |
Good Evening All,
Above all we must remember that the internal combustion engines all run by
the same rules whether they drive a lawn mower or are 3350s on a DC-7. The
differences are in the details, but the principles do not change. EGTs are
NOT the Holy Grail and the actual temperatures do not make any difference
at all. They can serve a very important duty in telling us how our engines
are doing if we understand that they are relative and not absolute.
LOP is best for longevity if you have adequate distribution. You can get
good distribution with a float carburetor or fuel injection, but it is easier
to get with fuel injection. The devil is in the details. They are all
marvelous things to behold. Don't get blinded by old wives tales. Study the
available knowledge and make your own decisions as you learn.
Happy Skies,
Old Bob
In a message dated 11/20/2010 9:42:35 P.M. Central Standard Time,
aerobiz1@gmail.com writes:
Hi again G.A.
Re shutdown :
It is not so much the temperature of the cylinder head, but more the
glowing embers of carbon or even a spark plug that will keep an engine running
-
albeit roughly - when you turn the ignition off. That's why we use the lean
cut-off on traditional aircraft engines. Starve the critter.....
At other times :
On a Jabiru, with its need to spin fast to get the ignition to fire, you
would not expect a broken earth lead - making the ignition always hot - to
be so much of a danger than it would be on a Lycoming with its
impulse-coupled magneto.
Pull through one blade, as slow as you lie, and you can easily fire the
engine up.
So there is a few techniques to shutting your engine down. If you don't
have a mixture cut-off like you would with a Rotec TBI or Aerocarb or
regular Lycoming type carb or fuel injection system, you can simply turn the
ignition off and hope that there are no glowing embers in a combustion chamber,
(if there is, push the throttle full open - often the technique used on
Gypsy Majors in Austers and Tiger Moths) or you can turn the fuel valve off
and wait for the Bing float bowl to empty.
Realistically, just turn the ignition off.....
Martin
On Sun, Nov 21, 2010 at 9:09 AM, <_zeprep251@aol.com_
(mailto:zeprep251@aol.com) > wrote:
Martin,your right,I should said when the engine is hot
My Beech 35,although injected with a mixture/ fuel cut off had a red line
cyl head temp of 435F.My Jabiru runs well under 300f, red lined at
325.Maybe the difference between cast and machined billet heads limits the temps
some.Should not have an issue with moving the prop and having it start
accidentally ,takes about 300rpm to fire the solid state pickup coil.but the
issue was shutting the Bing equipped engine down fuel wise.My Jabiru runs on
100LL as well.
Thanks G.A.
-----Original Message-----
From: Martin Hone <_aerobiz1@gmail.com_ (mailto:aerobiz1@gmail.com) >
(mailto:jabiruengine-list@matronics.com) >
Sent: Fri, Nov 19, 2010 9:54 pm
Subject: Re: JabiruEngine-List: Engine Shut Down
Hi G.A.
I wouldn;t be too sure about that. I think you will find that the CHT's
of any well running Continental or Lycoming are pretty much the same as for
a well running Jab. That would be between 300 and 380 degrees F in my
experience. The reason these engines use idle mixture cut-off is
1. Because they can
2. A broken 'P' lead won't allow the engine to fire if the prop is moved
3. Highly leaded fuels provide more material that can glow in the
combustion chamber and will keep the engine running-on even if the mags are
switched off.
Cheers
Martin
Message 8
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| Subject: | Re: Engine Shut Down |
Well said Bob,
Cheers
Martin
On Sun, Nov 21, 2010 at 2:01 PM, <BobsV35B@aol.com> wrote:
> Good Evening All,
>
> Above all we must remember that the internal combustion engines all run by
> the same rules whether they drive a lawn mower or are 3350s on a DC-7. The
> differences are in the details, but the principles do not change. EGTs are
> NOT the Holy Grail and the actual temperatures do not make any difference at
> all. They can serve a very important duty in telling us how our engines are
> doing if we understand that they are relative and not absolute.
>
> LOP is best for longevity if you have adequate distribution. You can get
> good distribution with a float carburetor or fuel injection, but it is
> easier to get with fuel injection. The devil is in the details. They are all
> marvelous things to behold. Don't get blinded by old wives tales. Study the
> available knowledge and make your own decisions as you learn.
>
> Happy Skies,
>
> Old Bob
>
> In a message dated 11/20/2010 9:42:35 P.M. Central Standard Time,
> aerobiz1@gmail.com writes:
>
> Hi again G.A.
>
> Re shutdown :
>
> It is not so much the temperature of the cylinder head, but more the
> glowing embers of carbon or even a spark plug that will keep an engine
> running - albeit roughly - when you turn the ignition off. That's why we use
> the lean cut-off on traditional aircraft engines. Starve the critter.....
>
> At other times :
>
> On a Jabiru, with its need to spin fast to get the ignition to fire, you
> would not expect a broken earth lead - making the ignition always hot - to
> be so much of a danger than it would be on a Lycoming with its
> impulse-coupled magneto.
> Pull through one blade, as slow as you lie, and you can easily fire the
> engine up.
>
> So there is a few techniques to shutting your engine down. If you don't
> have a mixture cut-off like you would with a Rotec TBI or Aerocarb or
> regular Lycoming type carb or fuel injection system, you can simply turn the
> ignition off and hope that there are no glowing embers in a combustion
> chamber, (if there is, push the throttle full open - often the technique
> used on Gypsy Majors in Austers and Tiger Moths) or you can turn the fuel
> valve off and wait for the Bing float bowl to empty.
> Realistically, just turn the ignition off.....
>
> Martin
>
> On Sun, Nov 21, 2010 at 9:09 AM, <zeprep251@aol.com> wrote:
>
>> Martin,your right,I should said when the engine is hot
>> My Beech 35,although injected with a mixture/ fuel cut off had a red line
>> cyl head temp of 435F.My Jabiru runs well under 300f, red lined at
>> 325.Maybe the difference between cast and machined billet heads limits the
>> temps some.Should not have an issue with moving the prop and having it start
>> accidentally ,takes about 300rpm to fire the solid state pickup coil.but the
>> issue was shutting the Bing equipped engine down fuel wise.My Jabiru runs on
>> 100LL as well.
>> Thanks G.A.
>>
>>
>> -----Original Message-----
>> From: Martin Hone <aerobiz1@gmail.com>
>> To: jabiruengine-list <jabiruengine-list@matronics.com>
>> Sent: Fri, Nov 19, 2010 9:54 pm
>> Subject: Re: JabiruEngine-List: Engine Shut Down
>>
>> Hi G.A.
>>
>> I wouldn;t be too sure about that. I think you will find that the CHT's
>> of any well running Continental or Lycoming are pretty much the same as for
>> a well running Jab. That would be between 300 and 380 degrees F in my
>> experience. The reason these engines use idle mixture cut-off is
>> 1. Because they can
>> 2. A broken 'P' lead won't allow the engine to fire if the prop is moved
>> 3. Highly leaded fuels provide more material that can glow in the
>> combustion chamber and will keep the engine running-on even if the mags are
>> switched off.
>>
>> Cheers
>>
>> Martin
>>
>>
>>
>>
> *
>
>
> *
>
>
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