Today's Message Index:
----------------------
1. 02:37 AM - Re: low compression on Jabiru engine using AVGAS (Keith Pickford)
2. 03:05 AM - Re: Jabiru electric circuit design, your comments?? (Rob Turk)
3. 07:24 AM - Re: low compression on Jabiru engine using AVGAS (BobsV35B@aol.com)
4. 07:39 AM - Re: low compression on Jabiru engine using AVGAS (BobsV35B@aol.com)
5. 11:27 AM - 3300 Install Questions (AZFlyer)
6. 03:57 PM - Re: low compression on Jabiru engine using AVGAS (Keith Pickford)
7. 04:06 PM - Re: low compression on Jabiru engine using AVGAS (Jabiru Chile)
8. 05:45 PM - Re: low compression on Jabiru engine using AVGAS (BobsV35B@aol.com)
Message 1
| INDEX | Back to Main INDEX |
| NEXT | Skip to NEXT Message |
| LIST | Reply to LIST Regarding this Message |
| SENDER | Reply to SENDER Regarding this Message |
|
| Subject: | Re: low compression on Jabiru engine using AVGAS |
Hi Christian
We have found that the high lead content of 100/130 can cause the top ring
to get tight in the ring groove. There is some interesting facts re the dif
ferent fuels in the January 2010 Jabba Chat on the Jabiru Au web site. It i
s also important to make sure the engine is not running lean. ie has the la
test recommended jetting. Of course that can vary if the engines aren't in
Jabiru airframes. It is also possible to get lead deposits stuck under a va
lve.
Will be interested to see what you find.
Regards
Keith
--- On Thu, 21/10/10, Jabiru Chile <info@jabiru.cl> wrote:
From: Jabiru Chile <info@jabiru.cl>
Subject: JabiruEngine-List: low compression on Jabiru engine using AVGAS
=0A=0A=0A =0A =0A=0A =0A=0A =0A=0A=0A=0A=0A=0A=0A=0AHi group, I have 3 engi
nes (3 different owners in different=0Acities) that are running on avgas 10
0/130 in=0A Chile , that after 80 hours are with=0Alow compression on 2 or
more cylinders. Have some of you any experience with=0Asame issue? 2 of the
se engines are flying in J450 and J430 and one of them is=0Amounted in a Ja
biru UL (2200). =0A=0APlease any commends will be appreciated, =0A=0A -
===========0A=0A
Message 2
| INDEX | Back to Main INDEX |
| PREVIOUS | Skip to PREVIOUS Message |
| NEXT | Skip to NEXT Message |
| LIST | Reply to LIST Regarding this Message |
| SENDER | Reply to SENDER Regarding this Message |
|
| Subject: | Re: Jabiru electric circuit design, your comments?? |
Hi Barry,
Thanks again for all the feedback!
The alternator is in fact the standard Jabiru 20A single-phase
generator/dynamo. Alternator is probably the wrong term here, although
Jabiru calls it a "Permanent Magnet Alternator".
Installing an automotive alternator would require major mechanical
modifications to run from the engine. With my mechanical skills this
would pose a much higher risk of failure than any of the wiring ;-) I
have seen pictures of one person running such a setup and I'm not up to
the task to make such mods..
The reason for running the generator/regulator output through the relay
is to enable overvoltage protection for COM, XPDR etc. If the regulator
fails (as it has in several documented cases) and spits out high
voltage, the OV crowbar would short-circuit the alternator contactor
relay. This short-circuit would make S2 (a combined switch/circuit
braker rated at 2A) trip, the relay would drop and the regulator output
would be disconnected from the bus. There are no other power sources
that can deliver more than 14V, so OV protection after that would not be
an issue.
The amp meter is indeed zero center. I am using a combined analog V/A
instrument (Westach 1022DA10-21). Max regulator output is 20A, and max
load is roughly the same. Under normal circumstances nothing over 30A
should ever occur.
The master switch is in the schematics, it's S1. It serves to activate
the battery contactor as well as the alternator relay (when S2 is also
engaged). Making it a circuit breaker would protect against shorts in
the contactor coil, not sure how likely that is. But worth considering.
I am not sure the regulator will bleed the remaining charge in the
capacitor quick enough. The Jabiru regulator schematics show the output
to be a switched rectifier bridge with diodes and thyristors. The diodes
are in reverse and would block any bleed current, hence the resistor.
With this resistor it would still take about 30 seconds to bleed to half
the voltage. Taking the cowl top off takes about two minutes, so any
accidental short after that should be harmless.
The regulator pins are defined in the Jabiru manual. 1 and 3 are AC in.
2 and case are ground. 4 is low voltage warning light. 5 is DC sense
feedback. 6 is regulated DC output. I will add the ground to the
regulator case in the diagram.
Good point on the starter indicator, will add that to the diagram as
well.
Great discussion, thanks!
Rob
----- Original Message -----
From: FLYaDIVE
To: jabiruengine-list@matronics.com
Sent: Thursday, October 21, 2010 12:07 AM
Subject: Re: JabiruEngine-List: Jabiru electric circuit design, your
comments??
Rob:
How is the alternator mechanical driven?
If it is belt driven - Go with a automotive alternator with a built
in Voltage Regulator - And you will have:
1 - Your crowbar circuit.
2 - elimination of the alternator contactor
3 - Elimination of the Jabriu Voltage Regulator and all that extra
STUFF.
And don't forget about the TIME and WIRING
For an alternator warning light a Voltage Comparator and LED will give
you the warning.
And it can be made to show when the battery is being charged.
-------------------------------------------------------------------------
----------
Now if you cannot go with the automotive alternator my next question
is:
Why the Alternator Contactor?
The Output of the Alternator can be tied DIRECTLY to the Battery Buss.
The circuit you have ADDS RESISTANCE and TWO (2) failure points:
1 - The Battery Contactor. INPUT & OUTPUT and
2 - Contactor coil and Wiring harness.
Some may say that is four (4) failure points.
I'm guessing that your Ammeter is a Zero Center movement?
If so, the deflection will be 0 to 30 Amps in either direction. <-- I
would go slightly higher because Nominal output is 30 Amps, you have no
surge leeway.
IS IT A 30 Amp Alternator?
Is the meter Analog or Digital?
If Analog the sensitivity to LOW current draws will be poor if not
nil.
If Digital check on the response of it.
I have always found a good SIMPLE volt meter is much better than an
Ammeter.
Small current discharges don't show up.
You will see it with your volt meter.
Your MASTER SWITCH:
I think you just did not put it in the schematic... But Use a Toggle
Circuit Breaker (amperage to match the contactor), I'm guessing 5 Amps.
The R/C circuit for filtering Good Idea... But eliminate the resistor.
There is enough LOW resistance in the alternator handle bleed down.
And 47K uF is good.... 100K uF is even better.
Question: What are pins 1, 3, 5 & 6 ?
Pin 6 LQQKs like Alternator output. OK
The Alternator itself should be Grounded Also.
STARTER:
Hang a LED off the OUTPUT of the Starter Contactor.
That way if the Contactor welds closed you will SEE the Lit LED and
can shut the engine down.
OK, that's all for now.
Barry
Message 3
| INDEX | Back to Main INDEX |
| PREVIOUS | Skip to PREVIOUS Message |
| NEXT | Skip to NEXT Message |
| LIST | Reply to LIST Regarding this Message |
| SENDER | Reply to SENDER Regarding this Message |
|
| Subject: | Re: low compression on Jabiru engine using AVGAS |
Good Morning Keith,
You wrote: "It is also important to make sure the engine is not running
lean"
Could you expand on this statement a bit? At lower power settings, lean is
the best place to be and at high power settings it is not. In either case,
lean is always relative and it should be on the lean side or on the rich
side relative to some operating parameter.
Don't you agree?
Happy Skies,
Old Bob
In a message dated 10/21/2010 4:37:22 A.M. Central Daylight Time,
kpickford@xtra.co.nz writes:
Hi Christian
We have found that the high lead content of 100/130 can cause the top ring
to get tight in the ring groove. There is some interesting facts re the
different fuels in the January 2010 Jabba Chat on the Jabiru Au web site. It
is also important to make sure the engine is not running lean. ie has the
latest recommended jetting. Of course that can vary if the engines aren't in
Jabiru airframes. It is also possible to get lead deposits stuck under a
valve.
Will be interested to see what you find.
Regards
Keith
--- On Thu, 21/10/10, Jabiru Chile <info@jabiru.cl> wrote:
From: Jabiru Chile <info@jabiru.cl>
Subject: JabiruEngine-List: low compression on Jabiru engine using AVGAS
Hi group, I have 3 engines (3 different owners in different cities) that
are running on avgas 100/130 in Chile , that after 80 hours are with low
compression on 2 or more cylinders. Have some of you any experience with same
issue? 2 of these engines are flying in J450 and J430 and one of them is
mounted in a Jabiru UL (2200).
Please any commends will be appreciated,
Christian
f="http://www.matronics.com/Navigator?JabiruEngine-List">http://www.matro="n
ofollow" target="_blank"
href="http://forums.matronics.com">http://www.matronics.com/contribution">http://www.matronics.com/contribution
============
(http://www.matronics.com/Navigator?JabiruEngine-List)
(http://www.matronics.com/contribution)
Message 4
| INDEX | Back to Main INDEX |
| PREVIOUS | Skip to PREVIOUS Message |
| NEXT | Skip to NEXT Message |
| LIST | Reply to LIST Regarding this Message |
| SENDER | Reply to SENDER Regarding this Message |
|
| Subject: | Re: low compression on Jabiru engine using AVGAS |
Good Morning Barry,
The last time I flew down south of the border, 100/130 AVGAS was still the
old mix and it had about three times the lead of 100LL. That means it has
about twelve times the lead of the old 80 Octane AVGAS. Really bad stuff for
a relatively low compression engine.
Could anyone tell us whether that is still the case?
Happy Skies,
Old Bob
In a message dated 10/20/2010 10:10:11 P.M. Central Daylight Time,
flyadive@gmail.com writes:
Christian:
There is a VERY good chance you are experiencing the same problems MANY
engines here in the USA are experiencing while running on 100LL. 100LL is
really not Low Lead at all. It is four times the lead as the old AvGas 80.
Since you are having low compression I would bet that they are
experiencing lead/coke build up in the valve stems.
If the build up goes untreated the valve will stick in the down (open)
position and if the valve - cylinder clearance is an interference fit they
will be spitting out valve parts. AND even if it is not an interference fit,
the compression will go to zero and still again they will be looking for an
emergency field and new engine parts.
The options are:
Use TCP in the fuel to reduce lead build up
LEAN AGGRESSIVELY - ALL THE TIMES -- Even when taxing.
Use AUTO - MoGas or a mixture of MoGas & AvGas. Just keep the octane
where needed.
1 hour flight before every oil change put in one quart of MMO (Marvell
Mystery Oil) - This helps clean the build up.
Now, these suggestion come with the limited information you gave. We don't
know how the engines are being run.
The time between oil changes.
The type of oil being used.
The quality of the gas and at least a dozen more items.
Since you identified that the engines have low compression - Have you
identified where they are leaking from?
Valves or Rings?
Any gasket leaks?
Fill in the blanks on the above questions and I'll try to diagnose.
GOOD LUCK,
Barry
On Wed, Oct 20, 2010 at 9:36 PM, Jabiru Chile <_info@jabiru.cl_
(mailto:info@jabiru.cl) > wrote:
Hi group, I have 3 engines (3 different owners in different cities) that
are running on avgas 100/130 in Chile, that after 80 hours are with low
compression on 2 or more cylinders. Have some of you any experience with same
issue? 2 of these engines are flying in J450 and J430 and one of them is
mounted in a Jabiru UL (2200).
Please any commends will be appreciated,
Christian
(http://www.matronics.com/Navigator?JabiruEngine-List)
(http://www.matronics.com/contribution)
Message 5
| INDEX | Back to Main INDEX |
| PREVIOUS | Skip to PREVIOUS Message |
| NEXT | Skip to NEXT Message |
| LIST | Reply to LIST Regarding this Message |
| SENDER | Reply to SENDER Regarding this Message |
|
| Subject: | 3300 Install Questions |
Jabiru installation Manual page 15 & 16 (Electrical Wiring Diagram) dated 24/1/2006,
shows items #37 & #38 "RF Suppressor Large and Small (P14A006N and P14A007N).
Does anybody know what these are, what they look like, or where to get
them, or a similar product?
Another question: Using 16 awg shielded wire to make P-leads for mag wires...where
are you grounding the shielded portion to "at the engine" as suggested.
thanks,
Mike
--------
Mike Miller @ millrml@aol.com
601 XL-B, 3300, Dynon
Remember, "the second mouse gets the cheese"!
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=316598#316598
Message 6
| INDEX | Back to Main INDEX |
| PREVIOUS | Skip to PREVIOUS Message |
| NEXT | Skip to NEXT Message |
| LIST | Reply to LIST Regarding this Message |
| SENDER | Reply to SENDER Regarding this Message |
|
| Subject: | Re: low compression on Jabiru engine using AVGAS |
Hi Bob
we had a engine "Blow" at 500 hours that was running lean. An early hydraulic lifter
2200 engine.
Jabiru bought out a revised tuning (jetting) for them.
Regards
Keith
--- On Fri, 22/10/10, BobsV35B@aol.com <BobsV35B@aol.com> wrote:
> From: BobsV35B@aol.com <BobsV35B@aol.com>
> Subject: Re: JabiruEngine-List: low compression on Jabiru engine using AVGAS
> To: jabiruengine-list@matronics.com
> Date: Friday, 22, October, 2010, 3:20 AM
>
>
>
>
>
> Good Morning Keith,
>
> You wrote: "It is also important to make sure the
> engine is not running
> lean"
>
> Could you expand on this statement a bit? At lower
> power settings, lean is
> the best place to be and at high power settings it is not.
> In either case, lean
> is always relative and it should be on the lean side or on
> the rich side
> relative to some operating parameter.
>
> Don't you agree?
>
> Happy Skies,
>
> Old Bob
>
>
> In a message dated 10/21/2010 4:37:22 A.M. Central
> Daylight Time,
> kpickford@xtra.co.nz writes:
>
>
>
>
> Hi Christian
>
> We have found that the high lead
> content of 100/130 can cause the top ring to get
> tight in the ring
> groove. There is some interesting facts re the
> different fuels in the
> January 2010 Jabba Chat on the Jabiru Au web site.
> It is also important
> to make sure the engine is not running lean. ie has
> the latest
> recommended jetting. Of course that can vary if the
> engines aren't in
> Jabiru airframes. It is also possible to get lead
> deposits stuck under a
> valve.
>
> Will be interested to see what you
> find.
>
> Regards
>
> Keith
>
> --- On Thu, 21/10/10, Jabiru
> Chile <info@jabiru.cl> wrote:
>
>
> From:
> Jabiru Chile <info@jabiru.cl>
> Subject: JabiruEngine-List: low
> compression on Jabiru engine using AVGAS
> To:
> jabiruengine-list@matronics.com
> Date: Thursday, 21, October, 2010,
> 2:36 PM
>
>
>
>
>
>
>
>
> Hi group, I have 3
> engines
> (3 different owners in different cities) that are
> running on avgas
> 100/130 in Chile , that after 80 hours are with
> low compression on 2
> or more cylinders. Have some of you any
> experience with same issue? 2
> of these engines are flying in J450 and J430 and
> one of them is
> mounted in a Jabiru UL (2200).
> Please any
> commends will
> be appreciated,
>
> Christianf="http://www.matronics.com/Navigator?JabiruEngine-List">http://www.matro="nofollow"
> target="_blank"
> href="http://forums.matronics.com">http://www.matronics.com/contribution">http://www.matronics.com/contribution===========
>
>
>
> ===================================
> List
> href="http://www.matronics.com/Navigator?JabiruEngine-List">http://www.matronics.com/Navigator?JabiruEngine-List
> ===================================
> ms.matronics.com/">http://forums.matronics.com
> ===================================
> tp://www.matronics.com/contribution">http://www.matronics.com/contribution
> ===================================
>
>
>
>
>
>
>
Message 7
| INDEX | Back to Main INDEX |
| PREVIOUS | Skip to PREVIOUS Message |
| NEXT | Skip to NEXT Message |
| LIST | Reply to LIST Regarding this Message |
| SENDER | Reply to SENDER Regarding this Message |
|
| Subject: | low compression on Jabiru engine using AVGAS |
Thank you Barry,
Thank you for the info. The info I can share is:
Engine (J3300 in J450), about 80 hours since new, using AVGAS100/130 since
first start in Chile, Oil used Shell aviation oil multigrade, Airplane build
to Jabiru standards with no extras other that ones offered by Jabiru, Jabiru
standard prop for this engine/airplane config., maintenance of engine
according to engine manual (oil changes, spark replace, oil filter, etc).
Leak are in two cylinders (more than others) and came from the exhaust
valves, but these two low compression cylinders where checked and the inside
of the cylinders looks not good with some scratches, probably done by the
rest of lead/coke build up in the combustion chamber or in top of the
pistons. Airplane is located 1000 km from Santiago and is flying by a Flying
Club.
Engine (J3300 in J430), about 80 hours since the pilot report low
compression 2 month ago. Same configuration than the above airplane, one
owner, flying near Santiago, and the problem found was in the exhaust
valves, but this airplane/engine have the economy tunning kit that Jabiru
offers for this engines.
Engine (J2200 in Jabiru UL), after a change of engine in the airplane, due
the original engine was from 1998 with 800 hours, was not worth to make an
overhaul, so the owner opt to change engine for a new model with longer
overhaul, hydraulic lifters, etc., but after about 70 hours and after a
maintenance check the mechanic found that the engine was not running good
and make a compression check. Same problem than above engines. Exhaust
valves not sealing, and after a clean up, was again with normal compression
and now the owner decide to use automobile gas 97 oct rating, unleaded.
I have also about 10 engines in Ultralight airplanes flying with automobile
gas 97 oct, and some of them with more than 800 hours, with compressions
like a new engine, so the AVGAS here in my conclusion is not the best for
Jabiru engines.
Thank you all for your support and info.
Regards,
Christian
_____
De: owner-jabiruengine-list-server@matronics.com
[mailto:owner-jabiruengine-list-server@matronics.com] En nombre de FLYaDIVE
Enviado el: Thursday, October 21, 2010 12:07 AM
Para: jabiruengine-list@matronics.com
Asunto: Re: JabiruEngine-List: low compression on Jabiru engine using AVGAS
Christian:
There is a VERY good chance you are experiencing the same problems MANY
engines here in the USA are experiencing while running on 100LL. 100LL is
really not Low Lead at all. It is four times the lead as the old AvGas 80.
Since you are having low compression I would bet that they are experiencing
lead/coke build up in the valve stems.
If the build up goes untreated the valve will stick in the down (open)
position and if the valve - cylinder clearance is an interference fit they
will be spitting out valve parts. AND even if it is not an interference
fit, the compression will go to zero and still again they will be looking
for an emergency field and new engine parts.
The options are:
Use TCP in the fuel to reduce lead build up
LEAN AGGRESSIVELY - ALL THE TIMES -- Even when taxing.
Use AUTO - MoGas or a mixture of MoGas & AvGas. Just keep the octane where
needed.
1 hour flight before every oil change put in one quart of MMO (Marvell
Mystery Oil) - This helps clean the build up.
Now, these suggestion come with the limited information you gave. We don't
know how the engines are being run.
The time between oil changes.
The type of oil being used.
The quality of the gas and at least a dozen more items.
Since you identified that the engines have low compression - Have you
identified where they are leaking from?
Valves or Rings?
Any gasket leaks?
Fill in the blanks on the above questions and I'll try to diagnose.
GOOD LUCK,
Barry
On Wed, Oct 20, 2010 at 9:36 PM, Jabiru Chile <info@jabiru.cl> wrote:
Hi group, I have 3 engines (3 different owners in different cities) that are
running on avgas 100/130 in Chile, that after 80 hours are with low
compression on 2 or more cylinders. Have some of you any experience with
same issue? 2 of these engines are flying in J450 and J430 and one of them
is mounted in a Jabiru UL (2200).
Please any commends will be appreciated,
Christian
Message 8
| INDEX | Back to Main INDEX |
| PREVIOUS | Skip to PREVIOUS Message |
| NEXT | Skip to NEXT Message |
| LIST | Reply to LIST Regarding this Message |
| SENDER | Reply to SENDER Regarding this Message |
|
| Subject: | Re: low compression on Jabiru engine using AVGAS |
Good Evening Keith,
I can understand that if it was running "Lean" when it should have been not
running "Lean", but that still does not answer the question. Lean in
relation to what?
And, at what power settings?
Makes a very big difference.
Happy Skies,
Old Bob
In a message dated 10/21/2010 5:57:40 P.M. Central Daylight Time,
kpickford@xtra.co.nz writes:
--> JabiruEngine-List message posted by: Keith Pickford
<kpickford@xtra.co.nz>
Hi Bob
we had a engine "Blow" at 500 hours that was running lean. An early
hydraulic lifter 2200 engine.
Jabiru bought out a revised tuning (jetting) for them.
Regards
Keith
--- On Fri, 22/10/10, BobsV35B@aol.com <BobsV35B@aol.com> wrote:
> From: BobsV35B@aol.com <BobsV35B@aol.com>
> Subject: Re: JabiruEngine-List: low compression on Jabiru engine using
AVGAS
> To: jabiruengine-list@matronics.com
> Date: Friday, 22, October, 2010, 3:20 AM
>
>
>
>
>
> Good Morning Keith,
>
> You wrote: "It is also important to make sure the
> engine is not running
> lean"
>
> Could you expand on this statement a bit? At lower
> power settings, lean is
> the best place to be and at high power settings it is not.
> In either case, lean
> is always relative and it should be on the lean side or on
> the rich side
> relative to some operating parameter.
>
> Don't you agree?
>
> Happy Skies,
>
> Old Bob
>
Other Matronics Email List Services
These Email List Services are sponsored solely by Matronics and through the generous Contributions of its members.
-- Please support this service by making your Contribution today! --
|