Today's Message Index:
----------------------
1. 05:47 AM - Re: 3300A - Full Throttle Roughness (Lynn Matteson)
2. 07:18 AM - Carby (BobbyPaulk@COMCAST.NET)
3. 08:19 AM - Full Thorttle Roughness Issue... (Don Honabach)
4. 10:49 AM - Re: Full Thorttle Roughness Issue... (Lynn Matteson)
5. 11:21 AM - Re: Full Thorttle Roughness Issue... (Andy Silvester)
6. 02:17 PM - Re: 3300A - Full Throttle Roughness (Peter Harris)
7. 02:23 PM - Re: 3300A - Full Throttle Roughness (Peter Harris)
8. 02:40 PM - Re: Full Thorttle Roughness Issue... (Peter Harris)
9. 02:46 PM - Re: Full Thorttle Roughness Issue... (Peter Harris)
10. 03:59 PM - Re: 3300A - Full Throttle Roughness (Lynn Matteson)
11. 08:17 PM - Re: 3300A - Full Throttle Roughness (Peter Harris)
12. 09:02 PM - Re: 3300A - Full Throttle Roughness (jetboy)
Message 1
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| Subject: | Re: 3300A - Full Throttle Roughness |
I'll have to report on the last inch of travel the next time I fly
it...I think I do get more power, but just how much I haven't paid
that much attention to.
I just bought a Northstar F210 fuel flow indicator, which is (I've
heard) similar to the Navman, but don't have it installed yet.
Regarding the seat removal...the first time I bought a seat,
directions came with it, but not the last two times. I used a slide-
hammer style device to pull the seat after first tapping the seat
body with a 5/16 24 tap...I think the directions called for an 8mm
tap, to which the 5/16-24 is close. I used the same slide hammer
device to install it, but substituted a close-fitting smooth mandrel
to drive it home.
Lynn Matteson
Kitfox IV Speedster, taildragger
Jabiru 2200, #2062, 600.2 hrs
Sensenich 62x46
Electroair direct-fire ignition system
New skis done and flying
On Jan 13, 2009, at 11:37 PM, Peter Harris wrote:
> <peterjfharris@bigpond.com>
>
> Lynn I think your 3.7mm seat should be fine with gravity feed. I found
> removal of the 2.25 seat and fitting the 1.5 seat made a very big
> difference
> to mixture at the higher throttle settings using the mech pump.
> Remove and
> refit was not easy, I made a screw puller and heated the carb to about
> 80degC. The seat is a tight interference fit.
> I am continuing with the fuel injection twin injector throttle
> body. At this
> stage no additional power but total control of mixture. I think the
> power
> output is limited by restricted flow through the Jab induction
> collector,
> but had problems using a tapered plenum due to the effect near WOT
> when most
> of the charge is delivered to the end into #1 and 2. I may spend
> some time
> building a bottom feed plenum later.
> I get very little increase in power over the last inch of throttle,
> do you
> also?
> I am also using a Navman fuel flow indicator and find it one of the
> most
> useful instruments especially for cross country when you can adjust
> throttle
> to get the desired fuel flow rate and also read fuel remaining
> accurate to
> 2%.
> Peter
>
> -----Original Message-----
> From: owner-jabiruengine-list-server@matronics.com
> [mailto:owner-jabiruengine-list-server@matronics.com] On Behalf Of
> Lynn
> Matteson
> Sent: Wednesday, 14 January 2009 8:29 AM
> To: jabiruengine-list@matronics.com
> Subject: Re: JabiruEngine-List: 3300A - Full Throttle Roughness
>
> <lynnmatt@jps.net>
>
> I wonder why the Bing folks here in Kansas, I think it is,
> recommended a 3.7 mm when I queried them about the gravity feed?
> (Granted, they are not the engineers that you spoke with.) Mine has
> worked really well since I went that route, which is not to say that
> it wouldn't work better with the 2.25. When I had the 1.5 mm in
> there, and pointed the nose up, in 10-15 seconds the thing would
> starve for fuel...pointing it down cured the starvation. That was
> with gravity feed. So I installed the recommended 3.7 mm, flow tested
> it, (catching the fuel as it ran right through the needle seat) and
> it would flow something like 13.5 gallons per hour, as I recall. I'm
> wondering if there would be any benefit to switching to the 2.25mm
> seat? It seems like too small is definitely bad, but too large I
> cannot see as a problem...do you?
>
> I've seen the effects that the rotation of the carb can have on the
> EGT's, and I've even thought of "sharpening" that central vane, but
> figured maybe Jab knew what they were doing leaving it rounded on the
> leading edge....thoughts?
>
> My air tube connection to the carb is a fiberglass 90 degree elbow
> with vanes inside to separate the flow into 4 equal (I hope)
> quadrants. This elbow allows the air to flow from straight above and
> behind the carb. I couldn't see much difference after I installed the
> vanes as opposed to having just the plain fiberglass tube. I used
> the exact same tube, slicing it vertically, and installing the thin
> fiberglass vanes...pics available if you'd like...then reassembling.
>
> How's that FI coming, of is it done?
>
>
> Lynn Matteson
> Kitfox IV Speedster, taildragger
> Jabiru 2200, #2062, 600.2 hrs
> Sensenich 62x46
> flying again after engine rebuild, and new Electroair direct-fire
> ignition system;
> also building a new pair of snow skis
>
>
> On Jan 13, 2009, at 4:03 PM, Peter Harris wrote:
>
>> <peterjfharris@bigpond.com>
>>
>> Lynn
>> According to the advice I got from the German Bing website engineer
>> The float valve needle seat for gravity feed is 2.25 and for pump
>> feed is
>> 1.5mm. I tried the 1,5mm seat and found it very I would say too
>> lean at
>> cruise because Jab has selected the power needle using the 2.25
>> seat/pump
>> combination tuned for economy cruise.
>> I conducted bench tests of the induction collector using a pressure
>> spray
>> gun and found that the alignment of the intake is absolutely
>> critical due to
>> the fact that inside the collector is a central vane. Any
>> misalignment of
>> the carb butterfly or of the carb on the hose attachment will cause
>> the
>> charge to favour one side or the other. If the distribution of the
>> charge is
>> bad the engine begins to "box" with uneven power strokes causing
>> vibration
>> (which I think may contribute to the flywheel bolts breakage). In
>> an extreme
>> case the engine may run bad rough.
>> Likewise poor scat hose configuration could contribute to the issue
>> and the
>> effect is suddenly greatest at or near WOT.
>> Peter
>>
>> -----Original Message-----
>> From: owner-jabiruengine-list-server@matronics.com
>> [mailto:owner-jabiruengine-list-server@matronics.com] On Behalf Of
>> Lynn
>> Matteson
>> Sent: Tuesday, 13 January 2009 7:29 PM
>> To: jabiruengine-list@matronics.com
>> Subject: Re: JabiruEngine-List: 3300A - Full Throttle Roughness
>>
>> <lynnmatt@jps.net>
>>
>> I've gone to gravity only in my 2200 high-wing Kitfox, removing the
>> mechanical AND the electric pump (that I rarely used before), and
>> installed the 3.7 mm float needle seat that Bing recommended. No
>> fuel issues any more for me.
>>
>> I would think that if you DID have a pressure-related problem with
>> the float needle/seat combo, that your suggestion of turning on the
>> boost pump ...at altitude....would reveal it. It did for me, when I
>> still had my electric pump. It was just too much pressure, so I
>> removed it, went with the gravity-only, and the 3.7 mm seat.
>>
>> Lynn Matteson
>> Kitfox IV Speedster, taildragger
>> Jabiru 2200, #2062, 600.2 hrs
>> Sensenich 62x46
>> flying again after engine rebuild, and new Electroair direct-fire
>> ignition system;
>> also building a new pair of snow skis
>> do not archive
>>
>>
>>
>> On Jan 13, 2009, at 1:55 AM, Don Honabach wrote:
>>
>>> Peter,
>>>
>>>
>>>
>>> Thanks for the quick reply.
>>>
>>>
>>>
>>> FYI, I have a low-wing design and during take-off I use an electric
>>> boost pump but during transition to cruise I turn it off and just
>>> use the engine driven mechanical fuel pump on the 3300A. Even with
>>> the boost pump, I don't exceed 3PSI (at least as much as I can
>>> trust the accuracy of the gauge at such low values and a narrow
>>> range).
>>>
>>>
>>>
>>> Assuming the needle leaking is the issue, is there a fix for non-
>>> gravity feed setups?
>>>
>>>
>>>
>>> As a side question, do those with gravity setups remove the engine
>>> driven pump?
>>>
>>>
>>>
>>> I'm assuming that if I turn on the boost pump during cruise and if
>>> I have a needle leak issue that the problem should be noticeable
>>> sooner or should be worse as the increased pressure will cause more
>>> leakage?
>>>
>>>
>>>
>>> I'll check the choke cable as well to make sure it is fully closing.
>>>
>>>
>>>
>>> Thanks!
>>> Don
>>>
>>>
>>>
>>>
>>>
>>>
>>>
>>> From: owner-jabiruengine-list-server@matronics.com [mailto:owner-
>>> jabiruengine-list-server@matronics.com] On Behalf Of Peter Harris
>>> Sent: Monday, January 12, 2009 23:21
>>> To: jabiruengine-list@matronics.com
>>> Subject: RE: JabiruEngine-List: 3300A - Full Throttle Roughness
>>>
>>>
>>>
>>> It sounds like it may be too rich under the load conditions at WOT
>>> cruise.
>>>
>>> The fuel bowl is fitted with 2.25mm needle valve seat which is
>>> meant for gravity feed, but they have selected the power needle as
>>> a compromise. If you are using a fuel pump it may cause the needle
>>> valve seat to leak and overfill the fuel bowl causing excessive
>>> rich mixture near max rpm.
>>>
>>> Another cause of over rich mixture is due to the starting choke not
>>> fully closing due to friction in the cable.
>>>
>>> Peter
>>>
>>>
>>>
>>> From: owner-jabiruengine-list-server@matronics.com [mailto:owner-
>>> jabiruengine-list-server@matronics.com] On Behalf Of Don Honabach
>>> Sent: Tuesday, 13 January 2009 4:03 PM
>>> To: jabiruengine-list@matronics.com
>>> Subject: JabiruEngine-List: 3300A - Full Throttle Roughness
>>>
>>>
>>>
>>> I'm having an issue where during cruise flight if I go full
>>> throttle either in straight and level or climb, the engine gets
>>> rough enough that it feels like it will quit. At this point, I
>>> obviously don't want to push the issue so I pull back on the
>>> throttle until the roughness goes away.
>>>
>>>
>>>
>>> Interestingly, I have no problem with full throttle roughness on
>>> take-off/climb-out.
>>>
>>>
>>>
>>> I also did some additional testing today and found that if I ease
>>> real slow into full throttle from cruise that I still get the
>>> roughness but not as bad and that the RPM will increase up to
>>> ~2,9xx and then start to degrade as I continue to add power along
>>> with additional roughness.
>>>
>>>
>>>
>>> Background info:
>>>
>>>
>>>
>>> Full Throttle Static RPM/Ground Run Up is ~2,800RPM. No issues with
>>> roughness.
>>>
>>>
>>>
>>> On my 601HDS, I have a 3300A with the Sensenich Carbon Prop (64"?
>>> 2A0J5R64Z-N) that was purchased from Jabiru USA/Pete K. back in
>>> 2006.
>>>
>>>
>>>
>>> Any help greatly appreciated. I've sent this same question to
>>> Jabiru USA and haven't gotten a response yet (sent last Thursday
>>> and sent another today asking for status).
>>>
>>>
>>>
>>> Initially thought it was the SCAT intake hose which I replaced with
>>> the rubber 90 degree elbow. Same issue with either intake method.
>>>
>>>
>>>
>>> Thanks!
>>>
>>> Don Honabach
>>>
>>> Tempe, AZ
>>>
>>>
>>>
>>> http://www.matronics.com/Navigator?JabiruEngine-List http://
>>> forums.matronics.com http://www.matronics.com/contribution
>>> &nbssp; - The JabiruEngine-List Email Forum utilities such as
>>> List Photoshare, and much much --> http://www.matronics.com/
>>> Navigator?JabiruEngine-Listhttp://forums.matronics.com -
>>> List Contribution Web generous nbsp; -->
>>> http://www.matronics.com/c
>>> Checked by AVG - http://www.avg.com
>>> 1/12/2009 07:04
>>>
>>> ============================================================ _-
>>> ============================================================ _-
>>> contribution_-
>>> ===========================================================
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>
>
Message 2
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List,
my carb was running VERY rich from off idle thru the whole range. i found the inlet
needle seat had a burr on it when it was factory drilled that kept the rubber
tipped needle valve from seating. i gently trimmed it with a larger drill
bit ( hand held ) and polished the seat with a wooden dowel and valve grinding
compound. this helped but i found out later that the older white floats were
not strong enough to seat the needle or maybe they were misaligned. the newer
black floats solved the problem. they are also Ethanol / alcohol tolerant. i
was not using Ethanol based fuel.
bobby
N131BP
DO NOT ARCHIVE.
Message 3
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| Subject: | Full Thorttle Roughness Issue... |
I just wanted to take moment and thank everyone that responded to my
question both on-list and off (WOW - just absolutely amazing the
response - THANK YOU!).
>From the various suggestions I decided that I needed to do a bit more
investigation...
During take-off AND WOT the EGTs on the right side of my engine are
significantly higher than the left. The max difference being ~1400
versus 1100F. However, during cruise, everything tends to even out but
now my left side (or at least cylinders #6 and #4) have higher EGTs than
the right side in general (~1359 verus 1290).
What is interesting is that my max RPM on take-off at WOT is ~2,850 and
there is no roughness at all despite the same EGT profile. In contrast,
when I do WOT in cruise the RPM maxes out at 3,000 and the roughness is
pretty bad and starts at about 2900RPM and gets worse as the RPM
increases. Also, pulling back so that the RPM is less than 2900 always
gets rid of the roughness.
So while the EGT profiles are essentially the same for both WOT
situations, it would appear that when the engine is capable of going
above 2900 RPM that the roughness occurs.
Any thoughts?
If interested, here are the two plot graphs for take-off and full power
cruise:
http://support.pcperfect.com/EGTs-TakeOff.pdf
http://support.pcperfect.com/EGTs-WOT-Cruise.pdf
Thanks!
Don
Message 4
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| Subject: | Re: Full Thorttle Roughness Issue... |
Don, have you modified the carb so that the throttle goes completely
wide open? This is a no-no, I'm told, and I think it is said that it
will lead to roughness at WOT if you do this. I understand that the
throttle should stop just short of a full 90 degree opening. Somebody
else who has the full story should comment....Pete? Jim? Andy?
Lynn Matteson
Kitfox IV Speedster, taildragger
Jabiru 2200, #2062, 600.2 hrs
Sensenich 62x46
Electroair direct-fire ignition system
New skis done and flying
do not archive
On Jan 14, 2009, at 11:18 AM, Don Honabach wrote:
> I just wanted to take moment and thank everyone that responded to
> my question both on-list and off (WOW - just absolutely amazing the
> response - THANK YOU!).
>
>
> From the various suggestions I decided that I needed to do a bit
> more investigation...
>
>
> During take-off AND WOT the EGTs on the right side of my engine are
> significantly higher than the left. The max difference being ~1400
> versus 1100F. However, during cruise, everything tends to even out
> but now my left side (or at least cylinders #6 and #4) have higher
> EGTs than the right side in general (~1359 verus 1290).
>
>
> What is interesting is that my max RPM on take-off at WOT is ~2,850
> and there is no roughness at all despite the same EGT profile. In
> contrast, when I do WOT in cruise the RPM maxes out at 3,000 and
> the roughness is pretty bad and starts at about 2900RPM and gets
> worse as the RPM increases. Also, pulling back so that the RPM is
> less than 2900 always gets rid of the roughness.
>
>
> So while the EGT profiles are essentially the same for both WOT
> situations, it would appear that when the engine is capable of
> going above 2900 RPM that the roughness occurs.
>
>
> Any thoughts?
>
>
> If interested, here are the two plot graphs for take-off and full
> power cruise:
>
>
> http://support.pcperfect.com/EGTs-TakeOff.pdf
>
> http://support.pcperfect.com/EGTs-WOT-Cruise.pdf
>
>
> Thanks!
> Don
>
>
> ============================================================ _-
> ============================================================ _-
> contribution_-
> ===========================================================
Message 5
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| Subject: | Full Thorttle Roughness Issue... |
This goes back to about 1996, with the first 2200s and the induction plenum.
Jabiru were head-scratching for a while trying to find out why (only some)
engines were running rough at WOT (my original 2200 powered Jabiru SK did)
and in the end found out the solution from BMW motorcycles. They also used
the 32mm CV carburettor and had a restriction at (I seem to recall) 75
degrees open for WOT, instead of 90 degrees, claiming that at 90 deg., the
bike would run rough......We deduced it had to do with turbulence over the
butterfly's assembly when edge-on to the flow. Since then, the throttle arm
on the carb. is made to restrict opening. However, since machined splitter
intakes and other developments, I personally doubt this is still an issue,
but then I haven't removed the restriction just to see what happens. My
money is on main-jet mixture if the engine runs rough at WOT.
Regards, Andy
-----Original Message-----
From: owner-jabiruengine-list-server@matronics.com
[mailto:owner-jabiruengine-list-server@matronics.com] On Behalf Of Lynn
Matteson
Sent: 14 January 2009 18:49
Subject: Re: JabiruEngine-List: Full Thorttle Roughness Issue...
Don, have you modified the carb so that the throttle goes completely
wide open? This is a no-no, I'm told, and I think it is said that it
will lead to roughness at WOT if you do this. I understand that the
throttle should stop just short of a full 90 degree opening. Somebody
else who has the full story should comment....Pete? Jim? Andy?
Lynn Matteson
Kitfox IV Speedster, taildragger
Jabiru 2200, #2062, 600.2 hrs
Sensenich 62x46
Electroair direct-fire ignition system
New skis done and flying
do not archive
On Jan 14, 2009, at 11:18 AM, Don Honabach wrote:
> I just wanted to take moment and thank everyone that responded to
> my question both on-list and off (WOW - just absolutely amazing the
> response - THANK YOU!).
>
>
> From the various suggestions I decided that I needed to do a bit
> more investigation...
>
>
> During take-off AND WOT the EGTs on the right side of my engine are
> significantly higher than the left. The max difference being ~1400
> versus 1100F. However, during cruise, everything tends to even out
> but now my left side (or at least cylinders #6 and #4) have higher
> EGTs than the right side in general (~1359 verus 1290).
>
>
> What is interesting is that my max RPM on take-off at WOT is ~2,850
> and there is no roughness at all despite the same EGT profile. In
> contrast, when I do WOT in cruise the RPM maxes out at 3,000 and
> the roughness is pretty bad and starts at about 2900RPM and gets
> worse as the RPM increases. Also, pulling back so that the RPM is
> less than 2900 always gets rid of the roughness.
>
>
> So while the EGT profiles are essentially the same for both WOT
> situations, it would appear that when the engine is capable of
> going above 2900 RPM that the roughness occurs.
>
>
> Any thoughts?
>
>
> If interested, here are the two plot graphs for take-off and full
> power cruise:
>
>
> http://support.pcperfect.com/EGTs-TakeOff.pdf
>
> http://support.pcperfect.com/EGTs-WOT-Cruise.pdf
>
>
> Thanks!
> Don
>
>
> ============================================================ _-
> ============================================================ _-
> contribution_-
> ===========================================================
Message 6
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| Subject: | 3300A - Full Throttle Roughness |
Lynn my tests were done on the ground in static runs. You could try the
throttle movement test on the ground for comparison.
I think after many hours of ground runs the last test I did with the plenum
proves that resistance in the Jab collector is affecting performance, as
follows:
1. Breakdown at WOT is caused by an unrestricted rush of fuel to the
end of the plenum to #1 and 2. In use of the tapered plenum there is only
one way to stop spectacular engine breakdown at WOT and that is by fitting a
full width baffle 35mm wide and 30mm from the entry inside the plenum.
2. The baffle neutralizes the effect of the butterfly so that the last
1" of throttle has no effect. The baffle is acting like a partly closed
butterfly downstream. Without the baffle, throttle increases power up to the
point of breakdown ie there is no dead throttle.
3. Similarly the last 1" of throttle into the Jab. collector has no
effect but because of internal losses there is normally no breakdown at WOT,
only #1 and 2 go rich.
My tests were conducted on the ground static. I am using a 55 X 72" prop. on
the Quickie which climbs at 1500FPM and cruises at 170KTS at 2950RPM WOT.
You can appreciate why I am trying to make sure the engine is doing it's
best. The engine is still very tight when hot. It has done about 50hours.
Peter
-----Original Message-----
From: owner-jabiruengine-list-server@matronics.com
[mailto:owner-jabiruengine-list-server@matronics.com] On Behalf Of Lynn
Matteson
Sent: Wednesday, 14 January 2009 11:46 PM
Subject: Re: JabiruEngine-List: 3300A - Full Throttle Roughness
I'll have to report on the last inch of travel the next time I fly
it...I think I do get more power, but just how much I haven't paid
that much attention to.
I just bought a Northstar F210 fuel flow indicator, which is (I've
heard) similar to the Navman, but don't have it installed yet.
Regarding the seat removal...the first time I bought a seat,
directions came with it, but not the last two times. I used a slide-
hammer style device to pull the seat after first tapping the seat
body with a 5/16 24 tap...I think the directions called for an 8mm
tap, to which the 5/16-24 is close. I used the same slide hammer
device to install it, but substituted a close-fitting smooth mandrel
to drive it home.
Lynn Matteson
Kitfox IV Speedster, taildragger
Jabiru 2200, #2062, 600.2 hrs
Sensenich 62x46
Electroair direct-fire ignition system
New skis done and flying
On Jan 13, 2009, at 11:37 PM, Peter Harris wrote:
> <peterjfharris@bigpond.com>
>
> Lynn I think your 3.7mm seat should be fine with gravity feed. I found
> removal of the 2.25 seat and fitting the 1.5 seat made a very big
> difference
> to mixture at the higher throttle settings using the mech pump.
> Remove and
> refit was not easy, I made a screw puller and heated the carb to about
> 80degC. The seat is a tight interference fit.
> I am continuing with the fuel injection twin injector throttle
> body. At this
> stage no additional power but total control of mixture. I think the
> power
> output is limited by restricted flow through the Jab induction
> collector,
> but had problems using a tapered plenum due to the effect near WOT
> when most
> of the charge is delivered to the end into #1 and 2. I may spend
> some time
> building a bottom feed plenum later.
> I get very little increase in power over the last inch of throttle,
> do you
> also?
> I am also using a Navman fuel flow indicator and find it one of the
> most
> useful instruments especially for cross country when you can adjust
> throttle
> to get the desired fuel flow rate and also read fuel remaining
> accurate to
> 2%.
> Peter
>
> -----Original Message-----
> From: owner-jabiruengine-list-server@matronics.com
> [mailto:owner-jabiruengine-list-server@matronics.com] On Behalf Of
> Lynn
> Matteson
> Sent: Wednesday, 14 January 2009 8:29 AM
> To: jabiruengine-list@matronics.com
> Subject: Re: JabiruEngine-List: 3300A - Full Throttle Roughness
>
> <lynnmatt@jps.net>
>
> I wonder why the Bing folks here in Kansas, I think it is,
> recommended a 3.7 mm when I queried them about the gravity feed?
> (Granted, they are not the engineers that you spoke with.) Mine has
> worked really well since I went that route, which is not to say that
> it wouldn't work better with the 2.25. When I had the 1.5 mm in
> there, and pointed the nose up, in 10-15 seconds the thing would
> starve for fuel...pointing it down cured the starvation. That was
> with gravity feed. So I installed the recommended 3.7 mm, flow tested
> it, (catching the fuel as it ran right through the needle seat) and
> it would flow something like 13.5 gallons per hour, as I recall. I'm
> wondering if there would be any benefit to switching to the 2.25mm
> seat? It seems like too small is definitely bad, but too large I
> cannot see as a problem...do you?
>
> I've seen the effects that the rotation of the carb can have on the
> EGT's, and I've even thought of "sharpening" that central vane, but
> figured maybe Jab knew what they were doing leaving it rounded on the
> leading edge....thoughts?
>
> My air tube connection to the carb is a fiberglass 90 degree elbow
> with vanes inside to separate the flow into 4 equal (I hope)
> quadrants. This elbow allows the air to flow from straight above and
> behind the carb. I couldn't see much difference after I installed the
> vanes as opposed to having just the plain fiberglass tube. I used
> the exact same tube, slicing it vertically, and installing the thin
> fiberglass vanes...pics available if you'd like...then reassembling.
>
> How's that FI coming, of is it done?
>
>
> Lynn Matteson
> Kitfox IV Speedster, taildragger
> Jabiru 2200, #2062, 600.2 hrs
> Sensenich 62x46
> flying again after engine rebuild, and new Electroair direct-fire
> ignition system;
> also building a new pair of snow skis
>
>
> On Jan 13, 2009, at 4:03 PM, Peter Harris wrote:
>
>> <peterjfharris@bigpond.com>
>>
>> Lynn
>> According to the advice I got from the German Bing website engineer
>> The float valve needle seat for gravity feed is 2.25 and for pump
>> feed is
>> 1.5mm. I tried the 1,5mm seat and found it very I would say too
>> lean at
>> cruise because Jab has selected the power needle using the 2.25
>> seat/pump
>> combination tuned for economy cruise.
>> I conducted bench tests of the induction collector using a pressure
>> spray
>> gun and found that the alignment of the intake is absolutely
>> critical due to
>> the fact that inside the collector is a central vane. Any
>> misalignment of
>> the carb butterfly or of the carb on the hose attachment will cause
>> the
>> charge to favour one side or the other. If the distribution of the
>> charge is
>> bad the engine begins to "box" with uneven power strokes causing
>> vibration
>> (which I think may contribute to the flywheel bolts breakage). In
>> an extreme
>> case the engine may run bad rough.
>> Likewise poor scat hose configuration could contribute to the issue
>> and the
>> effect is suddenly greatest at or near WOT.
>> Peter
>>
>> -----Original Message-----
>> From: owner-jabiruengine-list-server@matronics.com
>> [mailto:owner-jabiruengine-list-server@matronics.com] On Behalf Of
>> Lynn
>> Matteson
>> Sent: Tuesday, 13 January 2009 7:29 PM
>> To: jabiruengine-list@matronics.com
>> Subject: Re: JabiruEngine-List: 3300A - Full Throttle Roughness
>>
>> <lynnmatt@jps.net>
>>
>> I've gone to gravity only in my 2200 high-wing Kitfox, removing the
>> mechanical AND the electric pump (that I rarely used before), and
>> installed the 3.7 mm float needle seat that Bing recommended. No
>> fuel issues any more for me.
>>
>> I would think that if you DID have a pressure-related problem with
>> the float needle/seat combo, that your suggestion of turning on the
>> boost pump ...at altitude....would reveal it. It did for me, when I
>> still had my electric pump. It was just too much pressure, so I
>> removed it, went with the gravity-only, and the 3.7 mm seat.
>>
>> Lynn Matteson
>> Kitfox IV Speedster, taildragger
>> Jabiru 2200, #2062, 600.2 hrs
>> Sensenich 62x46
>> flying again after engine rebuild, and new Electroair direct-fire
>> ignition system;
>> also building a new pair of snow skis
>> do not archive
>>
>>
>>
>> On Jan 13, 2009, at 1:55 AM, Don Honabach wrote:
>>
>>> Peter,
>>>
>>>
>>>
>>> Thanks for the quick reply.
>>>
>>>
>>>
>>> FYI, I have a low-wing design and during take-off I use an electric
>>> boost pump but during transition to cruise I turn it off and just
>>> use the engine driven mechanical fuel pump on the 3300A. Even with
>>> the boost pump, I don't exceed 3PSI (at least as much as I can
>>> trust the accuracy of the gauge at such low values and a narrow
>>> range).
>>>
>>>
>>>
>>> Assuming the needle leaking is the issue, is there a fix for non-
>>> gravity feed setups?
>>>
>>>
>>>
>>> As a side question, do those with gravity setups remove the engine
>>> driven pump?
>>>
>>>
>>>
>>> I'm assuming that if I turn on the boost pump during cruise and if
>>> I have a needle leak issue that the problem should be noticeable
>>> sooner or should be worse as the increased pressure will cause more
>>> leakage?
>>>
>>>
>>>
>>> I'll check the choke cable as well to make sure it is fully closing.
>>>
>>>
>>>
>>> Thanks!
>>> Don
>>>
>>>
>>>
>>>
>>>
>>>
>>>
>>> From: owner-jabiruengine-list-server@matronics.com [mailto:owner-
>>> jabiruengine-list-server@matronics.com] On Behalf Of Peter Harris
>>> Sent: Monday, January 12, 2009 23:21
>>> To: jabiruengine-list@matronics.com
>>> Subject: RE: JabiruEngine-List: 3300A - Full Throttle Roughness
>>>
>>>
>>>
>>> It sounds like it may be too rich under the load conditions at WOT
>>> cruise.
>>>
>>> The fuel bowl is fitted with 2.25mm needle valve seat which is
>>> meant for gravity feed, but they have selected the power needle as
>>> a compromise. If you are using a fuel pump it may cause the needle
>>> valve seat to leak and overfill the fuel bowl causing excessive
>>> rich mixture near max rpm.
>>>
>>> Another cause of over rich mixture is due to the starting choke not
>>> fully closing due to friction in the cable.
>>>
>>> Peter
>>>
>>>
>>>
>>> From: owner-jabiruengine-list-server@matronics.com [mailto:owner-
>>> jabiruengine-list-server@matronics.com] On Behalf Of Don Honabach
>>> Sent: Tuesday, 13 January 2009 4:03 PM
>>> To: jabiruengine-list@matronics.com
>>> Subject: JabiruEngine-List: 3300A - Full Throttle Roughness
>>>
>>>
>>>
>>> I'm having an issue where during cruise flight if I go full
>>> throttle either in straight and level or climb, the engine gets
>>> rough enough that it feels like it will quit. At this point, I
>>> obviously don't want to push the issue so I pull back on the
>>> throttle until the roughness goes away.
>>>
>>>
>>>
>>> Interestingly, I have no problem with full throttle roughness on
>>> take-off/climb-out.
>>>
>>>
>>>
>>> I also did some additional testing today and found that if I ease
>>> real slow into full throttle from cruise that I still get the
>>> roughness but not as bad and that the RPM will increase up to
>>> ~2,9xx and then start to degrade as I continue to add power along
>>> with additional roughness.
>>>
>>>
>>>
>>> Background info:
>>>
>>>
>>>
>>> Full Throttle Static RPM/Ground Run Up is ~2,800RPM. No issues with
>>> roughness.
>>>
>>>
>>>
>>> On my 601HDS, I have a 3300A with the Sensenich Carbon Prop (64"?
>>> 2A0J5R64Z-N) that was purchased from Jabiru USA/Pete K. back in
>>> 2006.
>>>
>>>
>>>
>>> Any help greatly appreciated. I've sent this same question to
>>> Jabiru USA and haven't gotten a response yet (sent last Thursday
>>> and sent another today asking for status).
>>>
>>>
>>>
>>> Initially thought it was the SCAT intake hose which I replaced with
>>> the rubber 90 degree elbow. Same issue with either intake method.
>>>
>>>
>>>
>>> Thanks!
>>>
>>> Don Honabach
>>>
>>> Tempe, AZ
>>>
>>>
>>>
>>> http://www.matronics.com/Navigator?JabiruEngine-List http://
>>> forums.matronics.com http://www.matronics.com/contribution
>>> &nbssp; - The JabiruEngine-List Email Forum utilities such as
>>> List Photoshare, and much much --> http://www.matronics.com/
>>> Navigator?JabiruEngine-Listhttp://forums.matronics.com -
>>> List Contribution Web generous nbsp; -->
>>> http://www.matronics.com/c
>>> Checked by AVG - http://www.avg.com
>>> 1/12/2009 07:04
>>>
>>> ============================================================ _-
>>> ============================================================ _-
>>> contribution_-
>>> ===========================================================
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>
>
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| Subject: | 3300A - Full Throttle Roughness |
Stan,
The problem I have with that approach is that the selection of jets and
needles is being made to compensate for a leaking float valve needle seat.
The fuel needle seats are not all going to leak at the same rate.
It seems to me that this is a poor way to tune an engine. I think the carb
should first be assembled to Bing specifications for the application with
pump feed.
Then select jets and needles.
Peter
_____
From: owner-jabiruengine-list-server@matronics.com
[mailto:owner-jabiruengine-list-server@matronics.com] On Behalf Of Stanley
Challgren
Sent: Wednesday, 14 January 2009 3:39 PM
Subject: Re: JabiruEngine-List: 3300A - Full Throttle Roughness
Don:
I believe Jon's DVD "3300 Engine Installation" video may have the answer to
your problem. This was shot by Jon at one of Pete's engine installation
seminars.
Pete says on the video that at wide-open-throttle if you are getting too
much fuel it would result in cooler EGT's and shaking. If your EGT's are
closer to 1,000F than 1300F it is running cool due to the rich mixture. He
says the solution is a smaller main jet. He says about two-thirds of the
Jabiru engines have had to decrease their jet size. At another point he
says they are shipped with 285's and you should ask for the next lower.
bingcarb .com has a good book on the carb and it helped me with carb
problems on our first 3300 on a 601. Pete also said that they would be
carrying the smaller jets but you can also talk to the experts at Bing which
I believe is in Kansas.
For information on the 3300 installation I think Jon's DVD is a must have.
Five hours of excellent information.
Stan Challgren
701/3300
Evergreen, CO
On Jan 12, 2009, at 23:03 , Don Honabach wrote:
I'm having an issue where during cruise flight if I go full throttle either
in straight and level or climb, the engine gets rough enough that it feels
like it will quit. At this point, I obviously don't want to push the issue
so I pull back on the throttle until the roughness goes away.
Interestingly, I have no problem with full throttle roughness on
take-off/climb-out.
I also did some additional testing today and found that if I ease real slow
into full throttle from cruise that I still get the roughness but not as bad
and that the RPM will increase up to ~2,9xx and then start to degrade as I
continue to add power along with additional roughness.
Background info:
Full Throttle Static RPM/Ground Run Up is ~2,800RPM. No issues with
roughness.
On my 601HDS, I have a 3300A with the Sensenich Carbon Prop (64"?
2A0J5R64Z-N) that was purchased from Jabiru USA/Pete K. back in 2006.
Any help greatly appreciated. I've sent this same question to Jabiru USA and
haven't gotten a response yet (sent last Thursday and sent another today
asking for status).
Initially thought it was the SCAT intake hose which I replaced with the
rubber 90 degree elbow. Same issue with either intake method.
Thanks!
Don Honabach
Tempe, AZ
Message 8
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| Subject: | Full Thorttle Roughness Issue... |
Don,
During static runs and during climb at WOT the manifold pressure is
relatively close to 1 atmosphere but as the aircraft accelerates the vacuum
increases and manifold pressure goes down .
As manifold pressure varies, the distribution of the fuel/air mix through
the collector varies, and similarly as the velocity of incoming air
increases the turbulence and pressure profile through the system also
varies. Alignment of the butterfly also alters the distribution to R or L
because of the central vane in the collector.
Possibly removing that vane would improve the situation, but that would be a
challenge to the original development.
Like you I have also watched as EGT goes moves to favour R or L as the plane
accelerates to max cruise and on a couple of occasions encountered extreme
roughness due to the engine "boxing" with uneven power R to L due to the
difference in mixture. The engine started shaking.
But if you follow Pete's advice you should eventually find a setting that is
satisfactory. The charge distribution is never going to be perfect
throughout the power range .
Peter.
_____
From: owner-jabiruengine-list-server@matronics.com
[mailto:owner-jabiruengine-list-server@matronics.com] On Behalf Of Don
Honabach
Sent: Thursday, 15 January 2009 2:19 AM
Subject: JabiruEngine-List: Full Thorttle Roughness Issue...
I just wanted to take moment and thank everyone that responded to my
question both on-list and off (WOW - just absolutely amazing the response -
THANK YOU!).
>From the various suggestions I decided that I needed to do a bit more
investigation...
During take-off AND WOT the EGTs on the right side of my engine are
significantly higher than the left. The max difference being ~1400 versus
1100F. However, during cruise, everything tends to even out but now my left
side (or at least cylinders #6 and #4) have higher EGTs than the right side
in general (~1359 verus 1290).
What is interesting is that my max RPM on take-off at WOT is ~2,850 and
there is no roughness at all despite the same EGT profile. In contrast, when
I do WOT in cruise the RPM maxes out at 3,000 and the roughness is pretty
bad and starts at about 2900RPM and gets worse as the RPM increases. Also,
pulling back so that the RPM is less than 2900 always gets rid of the
roughness.
So while the EGT profiles are essentially the same for both WOT situations,
it would appear that when the engine is capable of going above 2900 RPM that
the roughness occurs.
Any thoughts?
If interested, here are the two plot graphs for take-off and full power
cruise:
http://support.pcperfect.com/EGTs-TakeOff.pdf
http://support.pcperfect.com/EGTs-WOT-Cruise.pdf
Thanks!
Don
Message 9
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| Subject: | Full Thorttle Roughness Issue... |
Lynn
That advice confirms my experience that WOT causes excess fuel to go to the
end of the collector enriching #1 and #2 but I believe that this is due to
the design of the collector and is costing power.
Peter.
-----Original Message-----
From: owner-jabiruengine-list-server@matronics.com
[mailto:owner-jabiruengine-list-server@matronics.com] On Behalf Of Lynn
Matteson
Sent: Thursday, 15 January 2009 4:49 AM
Subject: Re: JabiruEngine-List: Full Thorttle Roughness Issue...
Don, have you modified the carb so that the throttle goes completely
wide open? This is a no-no, I'm told, and I think it is said that it
will lead to roughness at WOT if you do this. I understand that the
throttle should stop just short of a full 90 degree opening. Somebody
else who has the full story should comment....Pete? Jim? Andy?
Lynn Matteson
Kitfox IV Speedster, taildragger
Jabiru 2200, #2062, 600.2 hrs
Sensenich 62x46
Electroair direct-fire ignition system
New skis done and flying
do not archive
On Jan 14, 2009, at 11:18 AM, Don Honabach wrote:
> I just wanted to take moment and thank everyone that responded to
> my question both on-list and off (WOW - just absolutely amazing the
> response - THANK YOU!).
>
>
> From the various suggestions I decided that I needed to do a bit
> more investigation...
>
>
> During take-off AND WOT the EGTs on the right side of my engine are
> significantly higher than the left. The max difference being ~1400
> versus 1100F. However, during cruise, everything tends to even out
> but now my left side (or at least cylinders #6 and #4) have higher
> EGTs than the right side in general (~1359 verus 1290).
>
>
> What is interesting is that my max RPM on take-off at WOT is ~2,850
> and there is no roughness at all despite the same EGT profile. In
> contrast, when I do WOT in cruise the RPM maxes out at 3,000 and
> the roughness is pretty bad and starts at about 2900RPM and gets
> worse as the RPM increases. Also, pulling back so that the RPM is
> less than 2900 always gets rid of the roughness.
>
>
> So while the EGT profiles are essentially the same for both WOT
> situations, it would appear that when the engine is capable of
> going above 2900 RPM that the roughness occurs.
>
>
> Any thoughts?
>
>
> If interested, here are the two plot graphs for take-off and full
> power cruise:
>
>
> http://support.pcperfect.com/EGTs-TakeOff.pdf
>
> http://support.pcperfect.com/EGTs-WOT-Cruise.pdf
>
>
> Thanks!
> Don
>
>
> ============================================================ _-
> ============================================================ _-
> contribution_-
> ===========================================================
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| Subject: | Re: 3300A - Full Throttle Roughness |
Peter-
Just to be sure I'm understanding your prop, I assume that you are
listing the diameter (55") first, and the pitch (72") second, as is
the normal way to describe a propellor, correct? (I've seen props
described the other way around, and their performance numbers didn't
add up) That seems like the only way that you could do 170 KTS at
2950 rpm...to me at least. That must be one very light aircraft to
climb that well and go that fast. You'll have to forgive me as I know
nothing about the Quickie. I would have thought that you'd have more
hours on your engine by now Peter....a lot of research and not much
flying, eh? : ) Maybe when you have more hours on the engine it will
loosen up and the effects of the last 1" of throttle travel will change?
I'm a bit confused by your description of the rush of fuel to the end
of the plenum to #1 and 2. It seems like the fuel must be being drawn
to those cylinders by vacuum from those cylinders. Do you suppose
this is because the fuel is not being atomized enough, and is
"clumping" together and cannot break apart to go to #3 and 4? This is
hard to visualize/imagine for me. I guess I do not understand your
description of the "tapered plenum" and how it works.
Lynn Matteson
Kitfox IV Speedster, taildragger
Jabiru 2200, #2062, 600.2 hrs
Sensenich 62x46
Electroair direct-fire ignition system
New skis done and flying
do not archive
On Jan 14, 2009, at 5:15 PM, Peter Harris wrote:
> <peterjfharris@bigpond.com>
>
> Lynn my tests were done on the ground in static runs. You could try
> the
> throttle movement test on the ground for comparison.
> I think after many hours of ground runs the last test I did with
> the plenum
> proves that resistance in the Jab collector is affecting
> performance, as
> follows:
>
> 1. Breakdown at WOT is caused by an unrestricted rush of fuel to the
> end of the plenum to #1 and 2. In use of the tapered plenum there
> is only
> one way to stop spectacular engine breakdown at WOT and that is by
> fitting a
> full width baffle 35mm wide and 30mm from the entry inside the plenum.
> 2. The baffle neutralizes the effect of the butterfly so that the last
> 1" of throttle has no effect. The baffle is acting like a partly
> closed
> butterfly downstream. Without the baffle, throttle increases power
> up to the
> point of breakdown ie there is no dead throttle.
> 3. Similarly the last 1" of throttle into the Jab. collector has no
> effect but because of internal losses there is normally no
> breakdown at WOT,
> only #1 and 2 go rich.
>
> My tests were conducted on the ground static. I am using a 55 X 72"
> prop. on
> the Quickie which climbs at 1500FPM and cruises at 170KTS at
> 2950RPM WOT.
> You can appreciate why I am trying to make sure the engine is doing
> it's
> best. The engine is still very tight when hot. It has done about
> 50hours.
>
> Peter
> -----Original Message-----
> From: owner-jabiruengine-list-server@matronics.com
> [mailto:owner-jabiruengine-list-server@matronics.com] On Behalf Of
> Lynn
> Matteson
> Sent: Wednesday, 14 January 2009 11:46 PM
> To: jabiruengine-list@matronics.com
> Subject: Re: JabiruEngine-List: 3300A - Full Throttle Roughness
>
> <lynnmatt@jps.net>
>
> I'll have to report on the last inch of travel the next time I fly
> it...I think I do get more power, but just how much I haven't paid
> that much attention to.
>
> I just bought a Northstar F210 fuel flow indicator, which is (I've
> heard) similar to the Navman, but don't have it installed yet.
>
> Regarding the seat removal...the first time I bought a seat,
> directions came with it, but not the last two times. I used a slide-
> hammer style device to pull the seat after first tapping the seat
> body with a 5/16 24 tap...I think the directions called for an 8mm
> tap, to which the 5/16-24 is close. I used the same slide hammer
> device to install it, but substituted a close-fitting smooth mandrel
> to drive it home.
>
> Lynn Matteson
> Kitfox IV Speedster, taildragger
> Jabiru 2200, #2062, 600.2 hrs
> Sensenich 62x46
> Electroair direct-fire ignition system
> New skis done and flying
>
>
> On Jan 13, 2009, at 11:37 PM, Peter Harris wrote:
>
>> <peterjfharris@bigpond.com>
>>
>> Lynn I think your 3.7mm seat should be fine with gravity feed. I
>> found
>> removal of the 2.25 seat and fitting the 1.5 seat made a very big
>> difference
>> to mixture at the higher throttle settings using the mech pump.
>> Remove and
>> refit was not easy, I made a screw puller and heated the carb to
>> about
>> 80degC. The seat is a tight interference fit.
>> I am continuing with the fuel injection twin injector throttle
>> body. At this
>> stage no additional power but total control of mixture. I think the
>> power
>> output is limited by restricted flow through the Jab induction
>> collector,
>> but had problems using a tapered plenum due to the effect near WOT
>> when most
>> of the charge is delivered to the end into #1 and 2. I may spend
>> some time
>> building a bottom feed plenum later.
>> I get very little increase in power over the last inch of throttle,
>> do you
>> also?
>> I am also using a Navman fuel flow indicator and find it one of the
>> most
>> useful instruments especially for cross country when you can adjust
>> throttle
>> to get the desired fuel flow rate and also read fuel remaining
>> accurate to
>> 2%.
>> Peter
>>
>> -----Original Message-----
>> From: owner-jabiruengine-list-server@matronics.com
>> [mailto:owner-jabiruengine-list-server@matronics.com] On Behalf Of
>> Lynn
>> Matteson
>> Sent: Wednesday, 14 January 2009 8:29 AM
>> To: jabiruengine-list@matronics.com
>> Subject: Re: JabiruEngine-List: 3300A - Full Throttle Roughness
>>
>> <lynnmatt@jps.net>
>>
>> I wonder why the Bing folks here in Kansas, I think it is,
>> recommended a 3.7 mm when I queried them about the gravity feed?
>> (Granted, they are not the engineers that you spoke with.) Mine has
>> worked really well since I went that route, which is not to say that
>> it wouldn't work better with the 2.25. When I had the 1.5 mm in
>> there, and pointed the nose up, in 10-15 seconds the thing would
>> starve for fuel...pointing it down cured the starvation. That was
>> with gravity feed. So I installed the recommended 3.7 mm, flow tested
>> it, (catching the fuel as it ran right through the needle seat) and
>> it would flow something like 13.5 gallons per hour, as I recall. I'm
>> wondering if there would be any benefit to switching to the 2.25mm
>> seat? It seems like too small is definitely bad, but too large I
>> cannot see as a problem...do you?
>>
>> I've seen the effects that the rotation of the carb can have on the
>> EGT's, and I've even thought of "sharpening" that central vane, but
>> figured maybe Jab knew what they were doing leaving it rounded on the
>> leading edge....thoughts?
>>
>> My air tube connection to the carb is a fiberglass 90 degree elbow
>> with vanes inside to separate the flow into 4 equal (I hope)
>> quadrants. This elbow allows the air to flow from straight above and
>> behind the carb. I couldn't see much difference after I installed the
>> vanes as opposed to having just the plain fiberglass tube. I used
>> the exact same tube, slicing it vertically, and installing the thin
>> fiberglass vanes...pics available if you'd like...then reassembling.
>>
>> How's that FI coming, of is it done?
>>
>>
>> Lynn Matteson
>> Kitfox IV Speedster, taildragger
>> Jabiru 2200, #2062, 600.2 hrs
>> Sensenich 62x46
>> flying again after engine rebuild, and new Electroair direct-fire
>> ignition system;
>> also building a new pair of snow skis
>>
>>
>>
>>
>> On Jan 13, 2009, at 4:03 PM, Peter Harris wrote:
>>
>>> <peterjfharris@bigpond.com>
>>>
>>> Lynn
>>> According to the advice I got from the German Bing website engineer
>>> The float valve needle seat for gravity feed is 2.25 and for pump
>>> feed is
>>> 1.5mm. I tried the 1,5mm seat and found it very I would say too
>>> lean at
>>> cruise because Jab has selected the power needle using the 2.25
>>> seat/pump
>>> combination tuned for economy cruise.
>>> I conducted bench tests of the induction collector using a pressure
>>> spray
>>> gun and found that the alignment of the intake is absolutely
>>> critical due to
>>> the fact that inside the collector is a central vane. Any
>>> misalignment of
>>> the carb butterfly or of the carb on the hose attachment will cause
>>> the
>>> charge to favour one side or the other. If the distribution of the
>>> charge is
>>> bad the engine begins to "box" with uneven power strokes causing
>>> vibration
>>> (which I think may contribute to the flywheel bolts breakage). In
>>> an extreme
>>> case the engine may run bad rough.
>>> Likewise poor scat hose configuration could contribute to the issue
>>> and the
>>> effect is suddenly greatest at or near WOT.
>>> Peter
>>>
>>> -----Original Message-----
>>> From: owner-jabiruengine-list-server@matronics.com
>>> [mailto:owner-jabiruengine-list-server@matronics.com] On Behalf Of
>>> Lynn
>>> Matteson
>>> Sent: Tuesday, 13 January 2009 7:29 PM
>>> To: jabiruengine-list@matronics.com
>>> Subject: Re: JabiruEngine-List: 3300A - Full Throttle Roughness
>>>
>>> <lynnmatt@jps.net>
>>>
>>> I've gone to gravity only in my 2200 high-wing Kitfox, removing the
>>> mechanical AND the electric pump (that I rarely used before), and
>>> installed the 3.7 mm float needle seat that Bing recommended. No
>>> fuel issues any more for me.
>>>
>>> I would think that if you DID have a pressure-related problem with
>>> the float needle/seat combo, that your suggestion of turning on the
>>> boost pump ...at altitude....would reveal it. It did for me, when I
>>> still had my electric pump. It was just too much pressure, so I
>>> removed it, went with the gravity-only, and the 3.7 mm seat.
>>>
>>> Lynn Matteson
>>> Kitfox IV Speedster, taildragger
>>> Jabiru 2200, #2062, 600.2 hrs
>>> Sensenich 62x46
>>> flying again after engine rebuild, and new Electroair direct-fire
>>> ignition system;
>>> also building a new pair of snow skis
>>> do not archive
>>>
>>>
>>>
>>> On Jan 13, 2009, at 1:55 AM, Don Honabach wrote:
>>>
>>>> Peter,
>>>>
>>>>
>>>>
>>>> Thanks for the quick reply.
>>>>
>>>>
>>>>
>>>> FYI, I have a low-wing design and during take-off I use an electric
>>>> boost pump but during transition to cruise I turn it off and just
>>>> use the engine driven mechanical fuel pump on the 3300A. Even with
>>>> the boost pump, I don't exceed 3PSI (at least as much as I can
>>>> trust the accuracy of the gauge at such low values and a narrow
>>>> range).
>>>>
>>>>
>>>>
>>>> Assuming the needle leaking is the issue, is there a fix for non-
>>>> gravity feed setups?
>>>>
>>>>
>>>>
>>>> As a side question, do those with gravity setups remove the engine
>>>> driven pump?
>>>>
>>>>
>>>>
>>>> I'm assuming that if I turn on the boost pump during cruise and if
>>>> I have a needle leak issue that the problem should be noticeable
>>>> sooner or should be worse as the increased pressure will cause more
>>>> leakage?
>>>>
>>>>
>>>>
>>>> I'll check the choke cable as well to make sure it is fully
>>>> closing.
>>>>
>>>>
>>>>
>>>> Thanks!
>>>> Don
>>>>
>>>>
>>>>
>>>>
>>>>
>>>>
>>>>
>>>> From: owner-jabiruengine-list-server@matronics.com [mailto:owner-
>>>> jabiruengine-list-server@matronics.com] On Behalf Of Peter Harris
>>>> Sent: Monday, January 12, 2009 23:21
>>>> To: jabiruengine-list@matronics.com
>>>> Subject: RE: JabiruEngine-List: 3300A - Full Throttle Roughness
>>>>
>>>>
>>>>
>>>> It sounds like it may be too rich under the load conditions at WOT
>>>> cruise.
>>>>
>>>> The fuel bowl is fitted with 2.25mm needle valve seat which is
>>>> meant for gravity feed, but they have selected the power needle as
>>>> a compromise. If you are using a fuel pump it may cause the needle
>>>> valve seat to leak and overfill the fuel bowl causing excessive
>>>> rich mixture near max rpm.
>>>>
>>>> Another cause of over rich mixture is due to the starting choke not
>>>> fully closing due to friction in the cable.
>>>>
>>>> Peter
>>>>
>>>>
>>>>
>>>> From: owner-jabiruengine-list-server@matronics.com [mailto:owner-
>>>> jabiruengine-list-server@matronics.com] On Behalf Of Don Honabach
>>>> Sent: Tuesday, 13 January 2009 4:03 PM
>>>> To: jabiruengine-list@matronics.com
>>>> Subject: JabiruEngine-List: 3300A - Full Throttle Roughness
>>>>
>>>>
>>>>
>>>> I'm having an issue where during cruise flight if I go full
>>>> throttle either in straight and level or climb, the engine gets
>>>> rough enough that it feels like it will quit. At this point, I
>>>> obviously don't want to push the issue so I pull back on the
>>>> throttle until the roughness goes away.
>>>>
>>>>
>>>>
>>>> Interestingly, I have no problem with full throttle roughness on
>>>> take-off/climb-out.
>>>>
>>>>
>>>>
>>>> I also did some additional testing today and found that if I ease
>>>> real slow into full throttle from cruise that I still get the
>>>> roughness but not as bad and that the RPM will increase up to
>>>> ~2,9xx and then start to degrade as I continue to add power along
>>>> with additional roughness.
>>>>
>>>>
>>>>
>>>> Background info:
>>>>
>>>>
>>>>
>>>> Full Throttle Static RPM/Ground Run Up is ~2,800RPM. No issues with
>>>> roughness.
>>>>
>>>>
>>>>
>>>> On my 601HDS, I have a 3300A with the Sensenich Carbon Prop (64"?
>>>> 2A0J5R64Z-N) that was purchased from Jabiru USA/Pete K. back in
>>>> 2006.
>>>>
>>>>
>>>>
>>>> Any help greatly appreciated. I've sent this same question to
>>>> Jabiru USA and haven't gotten a response yet (sent last Thursday
>>>> and sent another today asking for status).
>>>>
>>>>
>>>>
>>>> Initially thought it was the SCAT intake hose which I replaced with
>>>> the rubber 90 degree elbow. Same issue with either intake method.
>>>>
>>>>
>>>>
>>>> Thanks!
>>>>
>>>> Don Honabach
>>>>
>>>> Tempe, AZ
>>>>
>>>>
>>>>
>>>> http://www.matronics.com/Navigator?JabiruEngine-List http://
>>>> forums.matronics.com http://www.matronics.com/contribution
>>>> &nbssp; - The JabiruEngine-List Email Forum utilities such as
>>>> List Photoshare, and much much --> http://www.matronics.com/
>>>> Navigator?JabiruEngine-Listhttp://forums.matronics.com -
>>>> List Contribution Web generous nbsp; -->
>>>> http://www.matronics.com/c
>>>> Checked by AVG - http://www.avg.com
>>>> 1/12/2009 07:04
>>>>
>>>> ============================================================ _-
>>>> ============================================================ _-
>>>> contribution_-
>>>> ===========================================================
>>>
>>>
>>>
>>>
>>>
>>>
>>>
>>>
>>>
>>>
>>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>
>
Message 11
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| Subject: | 3300A - Full Throttle Roughness |
Lynn
The prop is 55 dia X 72 pitch.
The 500KG gross Quickie is a fast 2 seat low drag Rutan canard design and
rated at 200MPH when powered by an 0-200. Performance is similar to a
Varieze but with a shorter take off roll. The J 3300 advertises an extra
20HP and I am looking for the extra air speed but not satisfied the engine
is performing to full potential.
Feeding from a Jenvey throttle body with two injectors at WOT I am getting
much the same problem as referred when the Bing is fully open. Rough running
and according to my plugs it is caused by a surge of fuel to #1 and 2 at the
end of the plenum. With the plenum the rough running is extreme and causes
breakdown. With the Jab collector the effect is masked by losses in the
collector. As referred before I can fix the problem with the use of a large
baffle but this restricts the effect of the throttle and there is a loss of
power. There appears to me to be a similar loss in the Jab collector.
Therefore I don't think it is a Bing problem but based on the tests I have
done with a tapered plenum I think the problem is due to the design of the
plenum (also the Jab collector) by attempting to feed from the end and with
outlets along each side. By contrast if we look at the 0-200 the feed is an
updraft central between the four outlets and with equal length headers this
makes for uniform distribution over the full power range.
Near WOT when the butterfly is near level the Bing (and the Jenvey) fuel/air
charge although atomized the fuel droplets have sufficient energy to travel
to the end of the system and over richen #1 and 2.
The reason to taper the plenum is to attempt to get a uniform pressure
gradient along the axis allowing for expansion of the charge at each pair of
outlets. Take a look at a Dyson vacuum cleaner. It works well for air and it
works well when bench tested using water in a pressure paint spray gun but
apparently not for the fuel/air charge at the higher velocity under WOT.
When the butterfly is deflected further to reduce throttle the turbulence is
increased and the charge is more evenly distributed. Using the plenum
without the internal baffle I found that the butterfly position is critical
and the breakdown is sudden and complete.
I also tried with fuel pressure increased to 60PSI for better atomization
but without success.
Hope that helps, I tried to attach a pic of the plenum which does not look
very pretty but is sexy on the inside.
Re engine hours you are right I have spent too long on the ground
experimenting.
Peter
-----Original Message-----
From: owner-jabiruengine-list-server@matronics.com
[mailto:owner-jabiruengine-list-server@matronics.com] On Behalf Of Lynn
Matteson
Sent: Thursday, 15 January 2009 9:59 AM
Subject: Re: JabiruEngine-List: 3300A - Full Throttle Roughness
Peter-
Just to be sure I'm understanding your prop, I assume that you are
listing the diameter (55") first, and the pitch (72") second, as is
the normal way to describe a propellor, correct? (I've seen props
described the other way around, and their performance numbers didn't
add up) That seems like the only way that you could do 170 KTS at
2950 rpm...to me at least. That must be one very light aircraft to
climb that well and go that fast. You'll have to forgive me as I know
nothing about the Quickie. I would have thought that you'd have more
hours on your engine by now Peter....a lot of research and not much
flying, eh? : ) Maybe when you have more hours on the engine it will
loosen up and the effects of the last 1" of throttle travel will change?
I'm a bit confused by your description of the rush of fuel to the end
of the plenum to #1 and 2. It seems like the fuel must be being drawn
to those cylinders by vacuum from those cylinders. Do you suppose
this is because the fuel is not being atomized enough, and is
"clumping" together and cannot break apart to go to #3 and 4? This is
hard to visualize/imagine for me. I guess I do not understand your
description of the "tapered plenum" and how it works.
Lynn Matteson
Kitfox IV Speedster, taildragger
Jabiru 2200, #2062, 600.2 hrs
Sensenich 62x46
Electroair direct-fire ignition system
New skis done and flying
do not archive
On Jan 14, 2009, at 5:15 PM, Peter Harris wrote:
> <peterjfharris@bigpond.com>
>
> Lynn my tests were done on the ground in static runs. You could try
> the
> throttle movement test on the ground for comparison.
> I think after many hours of ground runs the last test I did with
> the plenum
> proves that resistance in the Jab collector is affecting
> performance, as
> follows:
>
> 1. Breakdown at WOT is caused by an unrestricted rush of fuel to the
> end of the plenum to #1 and 2. In use of the tapered plenum there
> is only
> one way to stop spectacular engine breakdown at WOT and that is by
> fitting a
> full width baffle 35mm wide and 30mm from the entry inside the plenum.
> 2. The baffle neutralizes the effect of the butterfly so that the last
> 1" of throttle has no effect. The baffle is acting like a partly
> closed
> butterfly downstream. Without the baffle, throttle increases power
> up to the
> point of breakdown ie there is no dead throttle.
> 3. Similarly the last 1" of throttle into the Jab. collector has no
> effect but because of internal losses there is normally no
> breakdown at WOT,
> only #1 and 2 go rich.
>
> My tests were conducted on the ground static. I am using a 55 X 72"
> prop. on
> the Quickie which climbs at 1500FPM and cruises at 170KTS at
> 2950RPM WOT.
> You can appreciate why I am trying to make sure the engine is doing
> it's
> best. The engine is still very tight when hot. It has done about
> 50hours.
>
> Peter
> -----Original Message-----
> From: owner-jabiruengine-list-server@matronics.com
> [mailto:owner-jabiruengine-list-server@matronics.com] On Behalf Of
> Lynn
> Matteson
> Sent: Wednesday, 14 January 2009 11:46 PM
> To: jabiruengine-list@matronics.com
> Subject: Re: JabiruEngine-List: 3300A - Full Throttle Roughness
>
> <lynnmatt@jps.net>
>
> I'll have to report on the last inch of travel the next time I fly
> it...I think I do get more power, but just how much I haven't paid
> that much attention to.
>
> I just bought a Northstar F210 fuel flow indicator, which is (I've
> heard) similar to the Navman, but don't have it installed yet.
>
> Regarding the seat removal...the first time I bought a seat,
> directions came with it, but not the last two times. I used a slide-
> hammer style device to pull the seat after first tapping the seat
> body with a 5/16 24 tap...I think the directions called for an 8mm
> tap, to which the 5/16-24 is close. I used the same slide hammer
> device to install it, but substituted a close-fitting smooth mandrel
> to drive it home.
>
> Lynn Matteson
> Kitfox IV Speedster, taildragger
> Jabiru 2200, #2062, 600.2 hrs
> Sensenich 62x46
> Electroair direct-fire ignition system
> New skis done and flying
>
>
> On Jan 13, 2009, at 11:37 PM, Peter Harris wrote:
>
>> <peterjfharris@bigpond.com>
>>
>> Lynn I think your 3.7mm seat should be fine with gravity feed. I
>> found
>> removal of the 2.25 seat and fitting the 1.5 seat made a very big
>> difference
>> to mixture at the higher throttle settings using the mech pump.
>> Remove and
>> refit was not easy, I made a screw puller and heated the carb to
>> about
>> 80degC. The seat is a tight interference fit.
>> I am continuing with the fuel injection twin injector throttle
>> body. At this
>> stage no additional power but total control of mixture. I think the
>> power
>> output is limited by restricted flow through the Jab induction
>> collector,
>> but had problems using a tapered plenum due to the effect near WOT
>> when most
>> of the charge is delivered to the end into #1 and 2. I may spend
>> some time
>> building a bottom feed plenum later.
>> I get very little increase in power over the last inch of throttle,
>> do you
>> also?
>> I am also using a Navman fuel flow indicator and find it one of the
>> most
>> useful instruments especially for cross country when you can adjust
>> throttle
>> to get the desired fuel flow rate and also read fuel remaining
>> accurate to
>> 2%.
>> Peter
>>
>> -----Original Message-----
>> From: owner-jabiruengine-list-server@matronics.com
>> [mailto:owner-jabiruengine-list-server@matronics.com] On Behalf Of
>> Lynn
>> Matteson
>> Sent: Wednesday, 14 January 2009 8:29 AM
>> To: jabiruengine-list@matronics.com
>> Subject: Re: JabiruEngine-List: 3300A - Full Throttle Roughness
>>
>> <lynnmatt@jps.net>
>>
>> I wonder why the Bing folks here in Kansas, I think it is,
>> recommended a 3.7 mm when I queried them about the gravity feed?
>> (Granted, they are not the engineers that you spoke with.) Mine has
>> worked really well since I went that route, which is not to say that
>> it wouldn't work better with the 2.25. When I had the 1.5 mm in
>> there, and pointed the nose up, in 10-15 seconds the thing would
>> starve for fuel...pointing it down cured the starvation. That was
>> with gravity feed. So I installed the recommended 3.7 mm, flow tested
>> it, (catching the fuel as it ran right through the needle seat) and
>> it would flow something like 13.5 gallons per hour, as I recall. I'm
>> wondering if there would be any benefit to switching to the 2.25mm
>> seat? It seems like too small is definitely bad, but too large I
>> cannot see as a problem...do you?
>>
>> I've seen the effects that the rotation of the carb can have on the
>> EGT's, and I've even thought of "sharpening" that central vane, but
>> figured maybe Jab knew what they were doing leaving it rounded on the
>> leading edge....thoughts?
>>
>> My air tube connection to the carb is a fiberglass 90 degree elbow
>> with vanes inside to separate the flow into 4 equal (I hope)
>> quadrants. This elbow allows the air to flow from straight above and
>> behind the carb. I couldn't see much difference after I installed the
>> vanes as opposed to having just the plain fiberglass tube. I used
>> the exact same tube, slicing it vertically, and installing the thin
>> fiberglass vanes...pics available if you'd like...then reassembling.
>>
>> How's that FI coming, of is it done?
>>
>>
>> Lynn Matteson
>> Kitfox IV Speedster, taildragger
>> Jabiru 2200, #2062, 600.2 hrs
>> Sensenich 62x46
>> flying again after engine rebuild, and new Electroair direct-fire
>> ignition system;
>> also building a new pair of snow skis
>>
>>
>>
>>
>> On Jan 13, 2009, at 4:03 PM, Peter Harris wrote:
>>
>>> <peterjfharris@bigpond.com>
>>>
>>> Lynn
>>> According to the advice I got from the German Bing website engineer
>>> The float valve needle seat for gravity feed is 2.25 and for pump
>>> feed is
>>> 1.5mm. I tried the 1,5mm seat and found it very I would say too
>>> lean at
>>> cruise because Jab has selected the power needle using the 2.25
>>> seat/pump
>>> combination tuned for economy cruise.
>>> I conducted bench tests of the induction collector using a pressure
>>> spray
>>> gun and found that the alignment of the intake is absolutely
>>> critical due to
>>> the fact that inside the collector is a central vane. Any
>>> misalignment of
>>> the carb butterfly or of the carb on the hose attachment will cause
>>> the
>>> charge to favour one side or the other. If the distribution of the
>>> charge is
>>> bad the engine begins to "box" with uneven power strokes causing
>>> vibration
>>> (which I think may contribute to the flywheel bolts breakage). In
>>> an extreme
>>> case the engine may run bad rough.
>>> Likewise poor scat hose configuration could contribute to the issue
>>> and the
>>> effect is suddenly greatest at or near WOT.
>>> Peter
>>>
>>> -----Original Message-----
>>> From: owner-jabiruengine-list-server@matronics.com
>>> [mailto:owner-jabiruengine-list-server@matronics.com] On Behalf Of
>>> Lynn
>>> Matteson
>>> Sent: Tuesday, 13 January 2009 7:29 PM
>>> To: jabiruengine-list@matronics.com
>>> Subject: Re: JabiruEngine-List: 3300A - Full Throttle Roughness
>>>
>>> <lynnmatt@jps.net>
>>>
>>> I've gone to gravity only in my 2200 high-wing Kitfox, removing the
>>> mechanical AND the electric pump (that I rarely used before), and
>>> installed the 3.7 mm float needle seat that Bing recommended. No
>>> fuel issues any more for me.
>>>
>>> I would think that if you DID have a pressure-related problem with
>>> the float needle/seat combo, that your suggestion of turning on the
>>> boost pump ...at altitude....would reveal it. It did for me, when I
>>> still had my electric pump. It was just too much pressure, so I
>>> removed it, went with the gravity-only, and the 3.7 mm seat.
>>>
>>> Lynn Matteson
>>> Kitfox IV Speedster, taildragger
>>> Jabiru 2200, #2062, 600.2 hrs
>>> Sensenich 62x46
>>> flying again after engine rebuild, and new Electroair direct-fire
>>> ignition system;
>>> also building a new pair of snow skis
>>> do not archive
>>>
>>>
>>>
>>> On Jan 13, 2009, at 1:55 AM, Don Honabach wrote:
>>>
>>>> Peter,
>>>>
>>>>
>>>>
>>>> Thanks for the quick reply.
>>>>
>>>>
>>>>
>>>> FYI, I have a low-wing design and during take-off I use an electric
>>>> boost pump but during transition to cruise I turn it off and just
>>>> use the engine driven mechanical fuel pump on the 3300A. Even with
>>>> the boost pump, I don't exceed 3PSI (at least as much as I can
>>>> trust the accuracy of the gauge at such low values and a narrow
>>>> range).
>>>>
>>>>
>>>>
>>>> Assuming the needle leaking is the issue, is there a fix for non-
>>>> gravity feed setups?
>>>>
>>>>
>>>>
>>>> As a side question, do those with gravity setups remove the engine
>>>> driven pump?
>>>>
>>>>
>>>>
>>>> I'm assuming that if I turn on the boost pump during cruise and if
>>>> I have a needle leak issue that the problem should be noticeable
>>>> sooner or should be worse as the increased pressure will cause more
>>>> leakage?
>>>>
>>>>
>>>>
>>>> I'll check the choke cable as well to make sure it is fully
>>>> closing.
>>>>
>>>>
>>>>
>>>> Thanks!
>>>> Don
>>>>
>>>>
>>>>
>>>>
>>>>
>>>>
>>>>
>>>> From: owner-jabiruengine-list-server@matronics.com [mailto:owner-
>>>> jabiruengine-list-server@matronics.com] On Behalf Of Peter Harris
>>>> Sent: Monday, January 12, 2009 23:21
>>>> To: jabiruengine-list@matronics.com
>>>> Subject: RE: JabiruEngine-List: 3300A - Full Throttle Roughness
>>>>
>>>>
>>>>
>>>> It sounds like it may be too rich under the load conditions at WOT
>>>> cruise.
>>>>
>>>> The fuel bowl is fitted with 2.25mm needle valve seat which is
>>>> meant for gravity feed, but they have selected the power needle as
>>>> a compromise. If you are using a fuel pump it may cause the needle
>>>> valve seat to leak and overfill the fuel bowl causing excessive
>>>> rich mixture near max rpm.
>>>>
>>>> Another cause of over rich mixture is due to the starting choke not
>>>> fully closing due to friction in the cable.
>>>>
>>>> Peter
>>>>
>>>>
>>>>
>>>> From: owner-jabiruengine-list-server@matronics.com [mailto:owner-
>>>> jabiruengine-list-server@matronics.com] On Behalf Of Don Honabach
>>>> Sent: Tuesday, 13 January 2009 4:03 PM
>>>> To: jabiruengine-list@matronics.com
>>>> Subject: JabiruEngine-List: 3300A - Full Throttle Roughness
>>>>
>>>>
>>>>
>>>> I'm having an issue where during cruise flight if I go full
>>>> throttle either in straight and level or climb, the engine gets
>>>> rough enough that it feels like it will quit. At this point, I
>>>> obviously don't want to push the issue so I pull back on the
>>>> throttle until the roughness goes away.
>>>>
>>>>
>>>>
>>>> Interestingly, I have no problem with full throttle roughness on
>>>> take-off/climb-out.
>>>>
>>>>
>>>>
>>>> I also did some additional testing today and found that if I ease
>>>> real slow into full throttle from cruise that I still get the
>>>> roughness but not as bad and that the RPM will increase up to
>>>> ~2,9xx and then start to degrade as I continue to add power along
>>>> with additional roughness.
>>>>
>>>>
>>>>
>>>> Background info:
>>>>
>>>>
>>>>
>>>> Full Throttle Static RPM/Ground Run Up is ~2,800RPM. No issues with
>>>> roughness.
>>>>
>>>>
>>>>
>>>> On my 601HDS, I have a 3300A with the Sensenich Carbon Prop (64"?
>>>> 2A0J5R64Z-N) that was purchased from Jabiru USA/Pete K. back in
>>>> 2006.
>>>>
>>>>
>>>>
>>>> Any help greatly appreciated. I've sent this same question to
>>>> Jabiru USA and haven't gotten a response yet (sent last Thursday
>>>> and sent another today asking for status).
>>>>
>>>>
>>>>
>>>> Initially thought it was the SCAT intake hose which I replaced with
>>>> the rubber 90 degree elbow. Same issue with either intake method.
>>>>
>>>>
>>>>
>>>> Thanks!
>>>>
>>>> Don Honabach
>>>>
>>>> Tempe, AZ
>>>>
>>>>
>>>>
>>>> http://www.matronics.com/Navigator?JabiruEngine-List http://
>>>> forums.matronics.com http://www.matronics.com/contribution
>>>> &nbssp; - The JabiruEngine-List Email Forum utilities such as
>>>> List Photoshare, and much much --> http://www.matronics.com/
>>>> Navigator?JabiruEngine-Listhttp://forums.matronics.com -
>>>> List Contribution Web generous nbsp; -->
>>>> http://www.matronics.com/c
>>>> Checked by AVG - http://www.avg.com
>>>> 1/12/2009 07:04
>>>>
>>>> ============================================================ _-
>>>> ============================================================ _-
>>>> contribution_-
>>>> ===========================================================
>>>
>>>
>>>
>>>
>>>
>>>
>>>
>>>
>>>
>>>
>>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>
>
Message 12
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| Subject: | Re: 3300A - Full Throttle Roughness |
If this is any help I recall reading on the lists about the rubber coupling from
carb to intake spider having a groove or step inside where fuel droplets cavitate
and sit in a pool at times of operation. some have dealt to this by fitting
an 'inner' sleeve tapered to make a smooth transition with no step.
Ralph
--------
Ralph - CH701 / 2200a
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http://forums.matronics.com/viewtopic.php?p=224860#224860
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