Today's Message Index:
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1. 03:27 PM - High EGT cyl 5 -running out of ideas (ple190)
2. 04:21 PM - Re: High EGT cyl 5 -running out of ideas (BobsV35B@aol.com)
3. 04:44 PM - Re: High EGT cyl 5 -running out of ideas (FLYaDIVE)
4. 06:23 PM - Re: High EGT cyl 5 -running out of ideas (ple190)
5. 06:40 PM - Re: Re: High EGT cyl 5 -running out of ideas (Nick Otterback)
6. 06:42 PM - Re: Re: High EGT cyl 5 -running out of ideas (FLYaDIVE)
7. 06:44 PM - Re: Re: High EGT cyl 5 -running out of ideas (FLYaDIVE)
8. 07:58 PM - Re: High EGT cyl 5 -running out of ideas (ple190)
9. 08:29 PM - Re: High EGT cyl 5 -running out of ideas (ple190)
10. 10:29 PM - Re: Re: High EGT cyl 5 -running out of ideas (FLYaDIVE)
Message 1
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| Subject: | High EGT cyl 5 -running out of ideas |
I,m running a 3300 in a Lightning .Main jet 255 needle 290. My main concern is
No 5 cylinder. At best econ (2800 rpm) ie just prior to needle to main changeover
No. 5 will peak around 760 Deg C (1400F) @ 2500ft OAT 10degC Thats about
50-60 deg C above all the others. The numbers are better up higher as expected
All the CHT's are good 120-130 C as are the oil T's & P's and the engine run
well, smooth through entire range
Normal cruise RPM of about 2900 is fine, EGT comes done to low 700's
On descent if i maintain 2900rpm no 5 EGT will again rise to 760-770 C
Should I be concerned ??
I have tried the following to resolve
1.carb tilt
2.intake vane
3.neddle jet increase 285-290
4.Checked for leaks in induction pipes/carby etc
5.swapped Sensors (reading was confirmed)
Any ideas ??
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=371932#371932
Message 2
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| Subject: | Re: High EGT cyl 5 -running out of ideas |
Good Evening plge190,
As a general rule, the actual temperature of the exhaust gas means very
little. What you really want to know is at what point it reaches peak in
relation to when other cylinders reach peak. If they all reach peak at the same
fuel flow, the mixture is perfectly balanced through out every cylinder.
The actual temperature can vary widely based on very small differences in
probe placement. If the cylinders all peak at fairly near the same fuel
flow, forget about it!
Al Hundere. the guru who got us all looking at EGTs, refused to list the
actual temperature as it is not at all pertinent to what we are trying to do.
Happy Skies,
Old Bob
In a message dated 4/27/2012 5:27:18 P.M. Central Daylight Time,
plge190@optusnet.com.au writes:
--> JabiruEngine-List message posted by: "ple190"
<plge190@optusnet.com.au>
I,m running a 3300 in a Lightning .Main jet 255 needle 290. My main
concern is No 5 cylinder. At best econ (2800 rpm) ie just prior to needle to main
changeover No. 5 will peak around 760 Deg C (1400F) @ 2500ft OAT 10degC
Thats about 50-60 deg C above all the others. The numbers are better up
higher as expected
All the CHT's are good 120-130 C as are the oil T's & P's and the engine
run well, smooth through entire range
Normal cruise RPM of about 2900 is fine, EGT comes done to low 700's
On descent if i maintain 2900rpm no 5 EGT will again rise to 760-770 C
Should I be concerned ??
I have tried the following to resolve
1.carb tilt
2.intake vane
3.neddle jet increase 285-290
4.Checked for leaks in induction pipes/carby etc
5.swapped Sensors (reading was confirmed)
Any ideas ??
Message 3
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| Subject: | Re: High EGT cyl 5 -running out of ideas |
Questions:
1 - Are all the EGT probes the same distance from the exhaust port flange?
2 - Is there any cooling air directed on the other probes, or air blockage
on #5?
3 - Are there any abrupt bends in #5 that do not exist in the other exhaust
headers?
Barry
On Fri, Apr 27, 2012 at 6:26 PM, ple190 <plge190@optusnet.com.au> wrote:
> >
>
> I,m running a 3300 in a Lightning .Main jet 255 needle 290. My main
> concern is No 5 cylinder. At best econ (2800 rpm) ie just prior to needle
> to main changeover No. 5 will peak around 760 Deg C (1400F) @ 2500ft OAT
> 10degC Thats about 50-60 deg C above all the others. The numbers are
> better up higher as expected
>
> All the CHT's are good 120-130 C as are the oil T's & P's and the engine
> run well, smooth through entire range
>
> Normal cruise RPM of about 2900 is fine, EGT comes done to low 700's
> On descent if i maintain 2900rpm no 5 EGT will again rise to 760-770 C
>
> Should I be concerned ??
>
> I have tried the following to resolve
> 1.carb tilt
> 2.intake vane
> 3.neddle jet increase 285-290
> 4.Checked for leaks in induction pipes/carby etc
> 5.swapped Sensors (reading was confirmed)
>
> Any ideas ??
>
>
> Read this topic online here:
>
> http://forums.matronics.com/viewtopic.php?p=371932#371932
>
>
Message 4
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| Subject: | Re: High EGT cyl 5 -running out of ideas |
Thanks for the input guys.
Old BOB ---The problem with the Jab and bing carb is no mixture control so you
have no way of knowing if your near peak EGT so I dont know if No 5 if at/near
or above peak EGT?
Barry --All the probs are in the same spot from the port. No 5 was a bit closer
so i moved it to match the others with no change ?
I will check if any cold air is being forced onto the senor
Paul
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=371949#371949
Message 5
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| Subject: | Re: High EGT cyl 5 -running out of ideas |
What SN lightning you have?
You can lean the bing with a little device called a HACman. We have been using
them on our Lightnings since 2008.
Also we do have a 4 way intake splitter installed at the carb throat. That seems
to get the egts all in line.
What prop are you running. We normally run 62fk58s here and use 250 main and 276-280
needles. Also engine SN would help and clean up kit?
Thanks
Nick
Sent from my pocket
On Apr 27, 2012, at 8:22 PM, "ple190" <plge190@optusnet.com.au> wrote:
>
> Thanks for the input guys.
> Old BOB ---The problem with the Jab and bing carb is no mixture control so you
have no way of knowing if your near peak EGT so I dont know if No 5 if at/near
or above peak EGT?
>
> Barry --All the probs are in the same spot from the port. No 5 was a bit closer
so i moved it to match the others with no change ?
> I will check if any cold air is being forced onto the senor
> Paul
>
>
>
>
> Read this topic online here:
>
> http://forums.matronics.com/viewtopic.php?p=371949#371949
>
>
>
>
>
>
>
>
>
>
Message 6
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| Subject: | Re: High EGT cyl 5 -running out of ideas |
Very good Paul.
I have lots of experience with Lycoming and I know the intake pipes are a
total mismatch. That is one major reason why they can not get even EGT
readings.
If your CHT is fairly uniform then I would not worry too much.
Have you tried a HOTTER spark plug on #5?
Why hotter - Because if the fuel is not completely burning in the cylinder
then it will burn in the exhaust pipe raising the EGT.
What Old Bob says is also VERY true. You do not know if you have reached
Peak EGT or the other cylinders are below #5.
Keep the group posted,
Barry
On Fri, Apr 27, 2012 at 9:22 PM, ple190 <plge190@optusnet.com.au> wrote:
> >
>
> Thanks for the input guys.
> Old BOB ---The problem with the Jab and bing carb is no mixture control so
> you have no way of knowing if your near peak EGT so I dont know if No 5 if
> at/near or above peak EGT?
>
> Barry --All the probs are in the same spot from the port. No 5 was a bit
> closer so i moved it to match the others with no change ?
> I will check if any cold air is being forced onto the senor
> Paul
>
>
> Read this topic online here:
>
> http://forums.matronics.com/viewtopic.php?p=371949#371949
>
>
Message 7
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| Subject: | Re: High EGT cyl 5 -running out of ideas |
Paul:
I had one more idea. You could Port & Polish the intake and exhaust ports
to gain an even flow and you will gain a few more HP too.
Barry
On Fri, Apr 27, 2012 at 9:22 PM, ple190 <plge190@optusnet.com.au> wrote:
> >
>
> Thanks for the input guys.
> Old BOB ---The problem with the Jab and bing carb is no mixture control so
> you have no way of knowing if your near peak EGT so I dont know if No 5 if
> at/near or above peak EGT?
>
> Barry --All the probs are in the same spot from the port. No 5 was a bit
> closer so i moved it to match the others with no change ?
> I will check if any cold air is being forced onto the senor
> Paul
>
>
> Read this topic online here:
>
> http://forums.matronics.com/viewtopic.php?p=371949#371949
>
>
Message 8
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| Subject: | Re: High EGT cyl 5 -running out of ideas |
Thanks Nick and Barry
Nick I have kit 104 with wheel fairing /pants installed and I'm running a 62FK58
prop
The eng is s/no 2246 so hyd lifter but not the latest induction manifold
Also I have a way splitter in the air box outlet which did help and have also
tried one in the smooth pipe thats on the carby intake and it didn't make any
difference.
My understanding of the Hackman is its a leaning device ? so not sure if this will
help ?
Barry do you have a part no for a hotter plug ? its worth a try
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=371967#371967
Message 9
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| Subject: | Re: High EGT cyl 5 -running out of ideas |
Nick- do you guys use the throttle extension on the carby ? I am and it limits
the amount of twist you can get.
Also looking at the jets you are using Nick may I'm running too rich and as Barry
said getting a burn in the exhaust pipe? I did increase the needle from 285
to 290 and it didn't help maybe even worse. I guess with the hackman I can lean
out and see what happens. At least I'll know how close to peak I am.
It runs well just don't want to do any damage !!
checked all the plugs the other day and they are all quite black and No. 5 is the
same as the others ?
I miss the good old days of steam gauges--or lack there of
"ignorance is bliss"
Paul
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=371968#371968
Message 10
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| Subject: | Re: High EGT cyl 5 -running out of ideas |
Paul:
The NGK Spark plug - D9EA is what is supplied with the engine... I
believe...
Below is the web site for NGK and there is a lot of info supplied. One
statement they make is an increase in heat range is a 70 to 100 Deg C
increase.
So, start by reading the chart on the site for Plug Condition (Reading the
plug). Then compare the plugs on the cylinders.
Then pick a heat range that a now educated guess would say should give you
the best results.
Spark Plug Color/Condition:
http://www.ngksparkplugs.com/tech_support/spark_plugs/faqs/faqread.asp
Heat Range Info:
http://www.ngksparkplugs.com/tech_support/spark_plugs/p2.asp?mode=nml
I spent a little time reading the site and there is a lot of info there.
LUCKILY NGK plugs are not expensive so you can experiment.
Oh, BTW, what kind of probe are you using for CHT's, Gasket type under the
spark plug? They read HIGH and when used the plug gasket should not be
used... Now, sometimes the plug gasket cannot be removed. What happens
when two gaskets are used, the plug height changes and the spark location
in the cylinder changes. AND two gaskets do not transfer heat as well as
as one gasket. This causes a plug to run HOTTER. Use any other type of
sensor that does not fit under the plug.
Barry
On Fri, Apr 27, 2012 at 10:57 PM, ple190 <plge190@optusnet.com.au> wrote:
> >
>
> Thanks Nick and Barry
> Nick I have kit 104 with wheel fairing /pants installed and I'm running a
> 62FK58 prop
> The eng is s/no 2246 so hyd lifter but not the latest induction manifold
> Also I have a way splitter in the air box outlet which did help and have
> also tried one in the smooth pipe thats on the carby intake and it didn't
> make any difference.
> My understanding of the Hackman is its a leaning device ? so not sure if
> this will help ?
>
> Barry do you have a part no for a hotter plug ? its worth a try
>
>
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