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High EGT's

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danb

Joined: 29 Sep 2010
Posts: 7

Posted: Wed May 23, 2012 6:27 pm Post subject: High EGT's

Bear with me as I'm a newbie breaking in a 912s. I recently started flying my Kitfox and now have 20 hours on it. I went flying yesterday morning and decided to fly her a little hotter than I normally have been doing at around 45-4600RPM (mostly to conserve fuel). I was told by a friend that also flies the same bird/engine and said I was babying it...so I pushed it at 5400 RPM. After flying for about an hour my Grand Rapids EIS started flashing me with high EGT's, but only on one side. I have all 4 sensors hooked up and the flash was showing me one side (both cylinders) dancing around 1600's and the other side was down around the 1400's where I read is about right.  I have searched and read several of the EGT issues so I have a bit of a handle on how many don't even show or worry about the EGT's and that the engine should not be tinkered with as it is set where it belongs at the factory. Also that the thing to really look at is the number spread...my thinking is now my numbers are out between the two sides. 

So, I'm looking for advice as I believe one side is probably running leaner than the other. I saw the post to take a look at the rubber boots and make sure of no cracks so I will do that. If ok, what should my next step be?

Thanks in advance,

Dan B

Mesa, AZ

jay(at)horriblehyde.com
Guest

Posted: Thu May 24, 2012 12:09 am Post subject: High EGT's

Check that your slides in the carburettors are opening at exactly the same

time; that was the problem that I had on my 582 with one cylinder running

hotter than the other.



Jay

--

joeing701(at)simnet.is
Guest

Posted: Thu May 24, 2012 2:49 am Post subject: High EGT's

Hello Dan.



Run your engine at 5000 rpm i.e. 75% power setting and you will see  

different EGT´s.  If not, you need to check your carbs to see what has  

changed. Could need some balancing at higher rpm.



Hope this will help.

Johann G.



On 24.5.2012, at 02:27, danb wrote:



 	  Quote: 	
		   



 Bear with me as I'm a newbie breaking in a 912s. I recently started  

 flying my Kitfox and now have 20 hours on it. I went flying  

 yesterday morning and decided to fly her a little hotter than I  

 normally have been doing at around 45-4600RPM (mostly to conserve  

 fuel). I was told by a friend that also flies the same bird/engine  

 and said I was babying it...so I pushed it at 5400 RPM. After flying  

 for about an hour my Grand Rapids EIS started flashing me with high  

 EGT's, but only on one side. I have all 4 sensors hooked up and the  

 flash was showing me one side (both cylinders) dancing around 1600's  

 and the other side was down around the 1400's where I read is about  

 right.  I have searched and read several of the EGT issues so I have  

 a bit of a handle on how many don't even show or worry about the  

 EGT's and that the engine should not be tinkered with as it is set  

 where it belongs at the factory. Also that the thing to really look  

 at is the number spread...my thinking is now my numbe!

 rs are out between the two sides.

 So, I'm looking for advice as I believe one side is probably running  

 leaner than the other. I saw the post to take a look at the rubber  

 boots and make sure of no cracks so I will do that. If ok, what  

 should my next step be?

 Thanks in advance,

 Dan B

 Mesa, AZ





 Read this topic online here:



 http://forums.matronics.com/viewtopic.php?p=373722#373722

Dick Maddux

Joined: 24 Jun 2008
Posts: 516
Location: Milton, Fl

Posted: Thu May 24, 2012 3:43 am Post subject: High EGT's

Dan,

  I wouldn't worry too much about the EGT's .Rpm's and carb needle setting will have an effect on the readings

  You should definately  not be cruising below 5000 rpm. The engine is designed to run above 5000. I was taught this in the 3 Rotax engine courses I have attended...which I very strongly advise you to try to put in your schedule if you want to maintain your engine properly.

                                              

                                      Dick Maddux

                                      Fox 4

                                      Milton,Fl

 [quote][b]

klinefelter.kevin(at)gmai
Guest

Posted: Thu May 24, 2012 5:09 am Post subject: High EGT's

Dick,

Excellent advice. 

Dan, How do your spark plugs look? If they are gapped properly and all the same tan/grey color all is well.

Kevin

Europa, 914



On May 24, 2012, at 4:42 AM, Catz631(at)aol.com (Catz631(at)aol.com) wrote:



[quote]    Dan,

  I wouldn't worry too much about the EGT's .Rpm's and carb needle setting will have an effect on the readings

  You should definately  not be cruising below 5000 rpm. The engine is designed to run above 5000. I was taught this in the 3 Rotax engine courses I have attended...which I very strongly advise you to try to put in your schedule if you want to maintain your engine properly.

                                              

                                      Dick Maddux

                                      Fox 4

                                      Milton,Fl

  	  Quote: 	
		  

	


[b]

Roger Lee

Joined: 10 Jan 2006
Posts: 1464
Location: Tucson, Az.

Posted: Thu May 24, 2012 5:49 am Post subject: Re: High EGT's

Hi Dan,



Other people are right about not cruising in the 4K rpm range. Your engine was never designed to run in that rpm for it's every day cruise. 5000-5400 rpm at cruise is normal and best for the engine. You are right that the normal EGT temps are in the 1400's. There are a few things that can cause those high EGT's. 1600 EGT is too high. It would be nice to know a couple of other numbers. What was the CHT and oil temps, were they high too? What is your WOT (wide open throttle) rpm? It should be around 5500-5600 rpm for normal every day flying. What is the spark plug gap set at? It should be between .023 - .027. The .027 is better for the summer temps and running. Out of curiosity what is your mag drop and at what rpm? Usually a mag drop of 50-90 is normal if done around 3500 rpm. Have the carbs been synced within the last 10 hrs?

If it was running okay on all EGT's for a while and then all of a sudden went to 1600 then you may have an obstruction in a carb bowl at the jet on that side. That would lean the fuel on that side and cause the EGT's to shoot up. An air leak could cause this and I doubt your carb boots are cracked, but make sure the carbs are snuggly in the rubber sockets.

Your comment about not altering the carbs because they are good to go at the factory settings for needle position is good advice. 



Give me a call if you have any other questions.

520-574-1080 



p.s. There are a few exceptions to carb needle position and prop pitch, but I doubt you are in that very select few.

_________________
Roger Lee
Tucson, Az.
Rotax Instructor & Rotax IRC
Light Sport Repairman
Home 520-574-1080 TRY HOME FIRST
Cell 520-349-7056

rickofudall

Joined: 19 Sep 2009
Posts: 1392
Location: Udall, KS, USA

Posted: Thu May 24, 2012 2:09 pm Post subject: High EGT's

If you have a way to disconnect the EGT senders, swap them from side to side and see if the temps stay the same or follow the senders.



Rick Girard



On Thu, May 24, 2012 at 8:08 AM,  <klinefelter.kevin(at)gmail.com (klinefelter.kevin(at)gmail.com)> wrote:

  	  Quote: 	
		  Dick,

Excellent advice. 

Dan, How do your spark plugs look? If they are gapped properly and all the same tan/grey color all is well.

 Kevin

Europa, 914



On May 24, 2012, at 4:42 AM, Catz631(at)aol.com (Catz631(at)aol.com) wrote:





 	  Quote: 	
		       Dan,

  I wouldn't worry too much about the EGT's .Rpm's and carb needle setting will have an effect on the readings

  You should definately  not be cruising below 5000 rpm. The engine is designed to run above 5000. I was taught this in the 3 Rotax engine courses I have attended...which I very strongly advise you to try to put in your schedule if you want to maintain your engine properly.

                                               

                                      Dick Maddux

                                      Fox 4

                                      Milton,Fl

  	  Quote: 	
		  

	






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 	  Quote: 	
		  

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3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D



	


	




-- 

Zulu Delta

Mk IIIC

Thanks, Homer GBYM

It isn't necessary to have relatives in Kansas City in order to be unhappy.

   - Groucho Marx



 

  [quote][b]

_________________
The smallest miracle right in front of you is enough to make you happy....

BARRY CHECK 6

Joined: 15 Mar 2011
Posts: 738

Posted: Thu May 24, 2012 5:15 pm Post subject: High EGT's

Dan:

Run the engine in the manufactures suggested operational range.  Monitor the EGT & CHT(if you have them).  Yea, yea, yea, I know you are water cooled and all cylinders should be the same... SHOULD BE!

 Do some tests as Richard suggested - This is to rule out the probes as being a problem.

BUT!  If you still see a 200 F differance between one side of the engine and the other.  And personally even at lower RPM's - There is something wrong when you have that high a EGT and with that wide of a temperature spread (200 F).  YES WORRY!

 Otherwise throw away the EGT gauge and taHell with indicators --- Ignorance is bliss.

Barry

On Thu, May 24, 2012 at 7:42 AM,  <Catz631(at)aol.com (Catz631(at)aol.com)> wrote:

 [quote]     Dan,

  I wouldn't worry too much about the EGT's .Rpm's and carb needle setting will have an effect on the readings

  You should definately  not be cruising below 5000 rpm. The engine is designed to run above 5000. I was taught this in the 3 Rotax engine courses I have attended...which I very strongly advise you to try to put in your schedule if you want to maintain your engine properly.

                                                

                                      Dick Maddux

                                      Fox 4

                                      Milton,Fl

  	  Quote: 	
		  



ist" target="_blank">http://www.matronics.com/Navigator?RotaxEngines-List

tp://forums.matronics.com

_blank">http://www.matronics.com/contribution



	




[b]

Dick Maddux

Joined: 24 Jun 2008
Posts: 516
Location: Milton, Fl

Posted: Fri May 25, 2012 4:05 am Post subject: High EGT's

Worry ..No. Investigate yes. Some good tips here Dan.(Swapping probes,etc)

 Also give Roger a call as he is very good on these engines.

  In the 912 classes I attended,they specifically mentioned that EGT is not a critical factor such as in a two stroke and don't put too much into it.(Oil press,temps,etc are.)It will vary greatly with rpm, fuel mixture,etc

   You could of course give Lockwood a call on their technical phone line which I have done on occasion.

  With the low time you have on your engine ,I think it is not likely (not impossible) that you have a problem with the engine. The EGT indication system COULD be at fault( or probe locations,etc)

                                      

                                                      Dick Maddux

                                                      912 UL

                                                      Milton,Fl

 [quote][b]

dan(at)azshowersolutions.
Guest

Posted: Fri May 25, 2012 4:06 am Post subject: High EGT's

Thank you all for your replies and ideas. I was able to get to the airport yesterday for a short time and pulled a couple plugs. The left side showed the even tan/grey color and the right side (the hot indicated side) showed a plug that was darker from the end of the threads to the electrodes. Didn't have enough time to pull any others, but that somewhat confirmed my sensors were not lying to me. I called and spoke with Roger at length last night and he had some good thoughts on how to approach / troubleshoot...thanks Roger! 

I know many put off the idea of being concerned with the EGT's, however, I am certainly with Barry on this one. I installed these sensors along with an engine monitor, they did their job, and I now know one side of the engine is running 200F  hotter than the other side. The Rotax manual lists 1620F as the MAX and the highest temp I saw was 1635F (I went back and listened to my digital recording I call out my numbers into instead of writing things down). I'm glad I had them hooked up as I can now look for a problem before it becomes catastrophic.

Thanks to all again

Dan

Mesa, AZ



[quote]        From: FLYaDIVE  <flyadive(at)gmail.com>

 To: rotaxengines-list(at)matronics.com 

 Sent: Thursday, May 24, 2012 6:13 PM

 Subject: Re: High EGT's

  

 

 Dan:

Run the engine in the manufactures suggested operational range.  Monitor the EGT & CHT(if you have them).  Yea, yea, yea, I know you are water cooled and all cylinders should be the same... SHOULD BE!

 Do some tests as Richard suggested - This is to rule out the probes as being a problem.

BUT!  If you still see a 200 F differance between one side of the engine and the other.  And personally even at lower RPM's - There is something wrong when you have that high a EGT and with that wide of a temperature spread (200 F).  YES WORRY!

 Otherwise throw away the EGT gauge and taHell with indicators --- Ignorance is bliss.

Barry

On Thu, May 24, 2012 at 7:42 AM,  <Catz631(at)aol.com (Catz631(at)aol.com)> wrote:

  	  Quote: 	
		       Dan,

  I wouldn't worry too much about the EGT's .Rpm's and carb needle setting will have an effect on the readings

  You should definately  not be cruising below 5000 rpm. The engine is designed to run above 5000. I was taught this in the 3 Rotax engine courses I have attended...which I very strongly advise you to try to put in your schedule if you want to maintain your engine properly.

                                                

                                      Dick Maddux

                                      Fox 4

                                      Milton,Fl

  	  Quote: 	
		  


ist" target="_blank">http://www.matronics.com/Navigator?RotaxEngines-List

tp://forums.matronics.com

_blank">http://www.matronics.com/contribution


	




http://www.matron======


	


 

 

 [b]

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