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EGT

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rijaeger(at)wausau.k12.wi
Guest

Posted: Thu Dec 08, 2011 7:17 am Post subject: EGT

'Anyone using an EGT they'd stand behind...? THANX!



  [quote][b]

brian(at)lloyd.com
Guest

Posted: Thu Dec 08, 2011 8:01 am Post subject: EGT

On Thu, Dec 8, 2011 at 7:15 AM, Rico Jaeger <rijaeger(at)wausau.k12.wi.us (rijaeger(at)wausau.k12.wi.us)> wrote:

 	  Quote: 	
		        'Anyone using an EGT they'd stand behind...? THANX!



	




For what? In order for EGT to be useful you need to know what you are going to do with it. First you have to understand that EGT readings are relative and not absolute. What the number is doesn't matter unless it is reading TIT and since none of our planes are turbocharged, you aren't going to have a TIT anyway. So the only way for EGT to be useful is if you have a way to vary the mixture.

 



As far as I have been able to discern, there is no use for a single-probe EGT unless you know for a fact that all cylinders have been matched for mixture. If not, you need a 9-probe EGT to be of any significant use. If you are running an M14P which has automatic mixture control, there is nothing you can do with the EGT readings except maybe use them to determine that you have one fouled plug. Huosai engines have a mixture control but I found that the single-probe EGT I had was not particularly useful in setting mixture. I had more luck setting mixture by ear. My attempts to run Lean of Peak (LoP) were not successful with the Huosai because the engine would surge, probably from a poorly adjusted carburetor, most likely because the mixture would change with flow. (Overly stiff diaphragm in the carb? Not sure.)

 



But let's say you do have an adjustable mixture, i.e. Huosai, M14P with a manual mixture modification, or Airflow Performance single-point FI. In that case you are looking for a good 9-point EGT system with either low-mass, fast-response probes (you want grounded probes with differential input to the display), or a display system that projects future EGT based on probe thermal lag response and rate-of-change of temperature. I am pretty sure that JPI fills the bill on this one.

 



I know, you asked the time and I came back with a discussion on building an atomic clock. Sorry. The problem is, once you get it you have to be able to do something with it. Adding another gauge to the panel for something you can do nothing about is a waste of money, panel space, and your pilot workload when you are flying. 

 

-- 

Brian Lloyd, WB6RQN/J79BPL

3191 Western Dr.

Cameron Park, CA 95682

brian(at)lloyd.com (brian(at)lloyd.com)

+1.767.617.1365 (Dominica)

+1.916.877.5067 (USA)

 

  [quote][b]

rijaeger(at)wausau.k12.wi
Guest

Posted: Thu Dec 08, 2011 8:15 am Post subject: EGT

Actually I was asking because the plane I picked up still has all 9 probes / cabling intact and in-place, AND an open hole in the panel. But thanks for allll that.

  

  

  

 



 	  Quote: 	
		  >> Brian Lloyd <brian(at)lloyd.com> 12/8/2011 9:58 AM >>>


	


 On Thu, Dec 8, 2011 at 7:15 AM, Rico Jaeger <rijaeger(at)wausau.k12.wi.us (rijaeger(at)wausau.k12.wi.us)> wrote:

  	  Quote: 	
		   'Anyone using an EGT they'd stand behind...? THANX!



	
 



 For what? In order for EGT to be useful you need to know what you are going to do with it. First you have to understand that EGT readings are relative and not absolute. What the number is doesn't matter unless it is reading TIT and since none of our planes are turbocharged, you aren't going to have a TIT anyway. So the only way for EGT to be useful is if you have a way to vary the mixture.

 



 As far as I have been able to discern, there is no use for a single-probe EGT unless you know for a fact that all cylinders have been matched for mixture. If not, you need a 9-probe EGT to be of any significant use. If you are running an M14P which has automatic mixture control, there is nothing you can do with the EGT readings except maybe use them to determine that you have one fouled plug. Huosai engines have a mixture control but I found that the single-probe EGT I had was not particularly useful in setting mixture. I had more luck setting mixture by ear. My attempts to run Lean of Peak (LoP) were not successful with the Huosai because the engine would surge, probably from a poorly adjusted carburetor, most likely because the mixture would change with flow. (Overly stiff diaphragm in the carb? Not sure.)

 



 But let's say you do have an adjustable mixture, i.e. Huosai, M14P with a manual mixture modification, or Airflow Performance single-point FI. In that case you are looking for a good 9-point EGT system with either low-mass, fast-response probes (you want grounded probes with differential input to the display), or a display system that projects future EGT based on probe thermal lag response and rate-of-change of temperature. I am pretty sure that JPI fills the bill on this one.

 



 I know, you asked the time and I came back with a discussion on building an atomic clock. Sorry. The problem is, once you get it you have to be able to do something with it. Adding another gauge to the panel for something you can do nothing about is a waste of money, panel space, and your pilot workload when you are flying. 

 

-- 

Brian Lloyd, WB6RQN/J79BPL

3191 Western Dr.

Cameron Park, CA 95682

brian(at)lloyd.com (brian(at)lloyd.com)

+1.767.617.1365 (Dominica)

+1.916.877.5067 (USA)



[quote]



ectric.com

">www.buildersbooks.com

builthelp.com

.matronics.com/contribution

://www.matronics.com/Navigator?Yak-List

ics.com

.matronics.com/contribution



[b]

brian(at)lloyd.com
Guest

Posted: Thu Dec 08, 2011 8:29 am Post subject: EGT

On Thu, Dec 8, 2011 at 8:12 AM, Rico Jaeger <rijaeger(at)wausau.k12.wi.us (rijaeger(at)wausau.k12.wi.us)> wrote:

 	  Quote: 	
		       Actually I was asking because the plane I picked up still has all 9 probes / cabling intact and in-place, AND an open hole in the panel. But thanks for allll that.



	




Well, the right answer is to install the same unit that came out so that all the cabling will work. Do you know what was there before? Since there are only a couple of companies making 9-probe EGT units, you can look at the part numbers on the probes and check with the manufacturers to see if they are their probes.

 



Good luck!



-- 

Brian Lloyd, WB6RQN/J79BPL

3191 Western Dr.

Cameron Park, CA 95682

brian(at)lloyd.com (brian(at)lloyd.com)

+1.767.617.1365 (Dominica)

 +1.916.877.5067 (USA)



  [quote][b]

rijaeger(at)wausau.k12.wi
Guest

Posted: Thu Dec 08, 2011 10:19 am Post subject: EGT

Great idea! I'll see what I can find...!

  

  

 



 	  Quote: 	
		  >> Brian Lloyd <brian(at)lloyd.com> 12/8/2011 10:27 AM >>>


	


 On Thu, Dec 8, 2011 at 8:12 AM, Rico Jaeger <rijaeger(at)wausau.k12.wi.us (rijaeger(at)wausau.k12.wi.us)> wrote:

  	  Quote: 	
		    Actually I was asking because the plane I picked up still has all 9 probes / cabling intact and in-place, AND an open hole in the panel. But thanks for allll that.



	
 



 Well, the right answer is to install the same unit that came out so that all the cabling will work. Do you know what was there before? Since there are only a couple of companies making 9-probe EGT units, you can look at the part numbers on the probes and check with the manufacturers to see if they are their probes.

 



 Good luck!

 

-- 

Brian Lloyd, WB6RQN/J79BPL

3191 Western Dr.

Cameron Park, CA 95682

brian(at)lloyd.com (brian(at)lloyd.com)

+1.767.617.1365 (Dominica)

+1.916.877.5067 (USA)



[quote]



ectric.com

">www.buildersbooks.com

builthelp.com

.matronics.com/contribution

://www.matronics.com/Navigator?Yak-List

ics.com

.matronics.com/contribution



[b]

dabear(at)devere.us
Guest

Posted: Thu Dec 08, 2011 7:44 pm Post subject: EGT

So, yes, having the EGT readings can help if you have a bad plug or wire.  It can also tell you when you left the primer cocked over/open  and it can tell you when you left the intake drain open.  It immediately tells you when you have a Cyl problem.  I think it is worth the installation as it saves time/cost in troubleshooting problems.

 

Bear

 

From: owner-yak-list-server(at)matronics.com [mailto:owner-yak-list-server(at)matronics.com] On Behalf Of Brian Lloyd

Sent: Thursday, December 08, 2011 10:59 AM

To: yak-list(at)matronics.com

Subject: Re: EGT

 

 

On Thu, Dec 8, 2011 at 7:15 AM, Rico Jaeger <rijaeger(at)wausau.k12.wi.us (rijaeger(at)wausau.k12.wi.us)> wrote:

'Anyone using an EGT they'd stand behind...? THANX!



 



For what? In order for EGT to be useful you need to know what you are going to do with it. First you have to understand that EGT readings are relative and not absolute. What the number is doesn't matter unless it is reading TIT and since none of our planes are turbocharged, you aren't going to have a TIT anyway. So the only way for EGT to be useful is if you have a way to vary the mixture.



 



As far as I have been able to discern, there is no use for a single-probe EGT unless you know for a fact that all cylinders have been matched for mixture. If not, you need a 9-probe EGT to be of any significant use. If you are running an M14P which has automatic mixture control, there is nothing you can do with the EGT readings except maybe use them to determine that you have one fouled plug. Huosai engines have a mixture control but I found that the single-probe EGT I had was not particularly useful in setting mixture. I had more luck setting mixture by ear. My attempts to run Lean of Peak (LoP) were not successful with the Huosai because the engine would surge, probably from a poorly adjusted carburetor, most likely because the mixture would change with flow. (Overly stiff diaphragm in the carb? Not sure.)



 



But let's say you do have an adjustable mixture, i.e. Huosai, M14P with a manual mixture modification, or Airflow Performance single-point FI. In that case you are looking for a good 9-point EGT system with either low-mass, fast-response probes (you want grounded probes with differential input to the display), or a display system that projects future EGT based on probe thermal lag response and rate-of-change of temperature. I am pretty sure that JPI fills the bill on this one.



 



I know, you asked the time and I came back with a discussion on building an atomic clock. Sorry. The problem is, once you get it you have to be able to do something with it. Adding another gauge to the panel for something you can do nothing about is a waste of money, panel space, and your pilot workload when you are flying. 



 

-- 

Brian Lloyd, WB6RQN/J79BPL

3191 Western Dr.

Cameron Park, CA 95682

brian(at)lloyd.com (brian(at)lloyd.com)

+1.767.617.1365 (Dominica)

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  [quote][b]

ReadeG(at)cairnwood.com
Guest

Posted: Thu Dec 08, 2011 7:59 pm Post subject: EGT

A rough running engine will tell you all that too!  A simple check with a laser pyrometer ($80) will tell you which cylinder is cold on mag and plug issues. Primer and intake is easily identified by rough idle and visual cockpit check.   If you don’t have a way to lean the 9 probe egt is pretty useless.

 

Reade Genzlinger

Cairnwood Cooperative Corp.

215.914.0370



 

From: owner-yak-list-server(at)matronics.com [mailto:owner-yak-list-server(at)matronics.com] On Behalf Of dabear(at)devere.us

Sent: Thursday, December 08, 2011 10:40 PM

To: yak-list(at)matronics.com

Subject: RE: EGT

 

So, yes, having the EGT readings can help if you have a bad plug or wire.  It can also tell you when you left the primer cocked over/open  and it can tell you when you left the intake drain open.  It immediately tells you when you have a Cyl problem.  I think it is worth the installation as it saves time/cost in troubleshooting problems.

 

Bear 	  Quote: 	
		   	


 [quote][b]

viperdoc(at)mindspring.co
Guest

Posted: Thu Dec 08, 2011 8:06 pm Post subject: EGT

Also tells you if your shutters have crept closed.

Doc



Sent from my iPad



On Dec 8, 2011, at 9:40 PM, <dabear(at)devere.us (dabear(at)devere.us)> wrote:



[quote]

So, yes, having the EGT readings can help if you have a bad plug or wire.  It can also tell you when you left the primer cocked over/open  and it can tell you when you left the intake drain open.  It immediately tells you when you have a Cyl problem.  I think it is worth the installation as it saves time/cost in troubleshooting problems.

 

Bear

 

From: owner-yak-list-server(at)matronics.com (owner-yak-list-server(at)matronics.com) [mailto:owner-yak-list-server(at)matronics.com] On Behalf Of Brian Lloyd

Sent: Thursday, December 08, 2011 10:59 AM

To: [url=mailto:yak-list(at)matronics.com]yak-list(at)matronics.com (yak-list(at)matronics.com)[/url]

Subject: Re: EGT

 

 

On Thu, Dec 8, 2011 at 7:15 AM, Rico Jaeger <[url=mailto:rijaeger(at)wausau.k12.wi.us]rijaeger(at)wausau.k12.wi.us (rijaeger(at)wausau.k12.wi.us)[/url]> wrote:

'Anyone using an EGT they'd stand behind...? THANX!



 



For what? In order for EGT to be useful you need to know what you are going to do with it. First you have to understand that EGT readings are relative and not absolute. What the number is doesn't matter unless it is reading TIT and since none of our planes are turbocharged, you aren't going to have a TIT anyway. So the only way for EGT to be useful is if you have a way to vary the mixture.



 



As far as I have been able to discern, there is no use for a single-probe EGT unless you know for a fact that all cylinders have been matched for mixture. If not, you need a 9-probe EGT to be of any significant use. If you are running an M14P which has automatic mixture control, there is nothing you can do with the EGT readings except maybe use them to determine that you have one fouled plug. Huosai engines have a mixture control but I found that the single-probe EGT I had was not particularly useful in setting mixture. I had more luck setting mixture by ear. My attempts to run Lean of Peak (LoP) were not successful with the Huosai because the engine would surge, probably from a poorly adjusted carburetor, most likely because the mixture would change with flow. (Overly stiff diaphragm in the carb? Not sure.)



 



But let's say you do have an adjustable mixture, i.e. Huosai, M14P with a manual mixture modification, or Airflow Performance single-point FI. In that case you are looking for a good 9-point EGT system with either low-mass, fast-response probes (you want grounded probes with differential input to the display), or a display system that projects future EGT based on probe thermal lag response and rate-of-change of temperature. I am pretty sure that JPI fills the bill on this one.



 



I know, you asked the time and I came back with a discussion on building an atomic clock. Sorry. The problem is, once you get it you have to be able to do something with it. Adding another gauge to the panel for something you can do nothing about is a waste of money, panel space, and your pilot workload when you are flying. 



 

-- 

Brian Lloyd, WB6RQN/J79BPL

3191 Western Dr.

Cameron Park, CA 95682

[url=mailto:brian(at)lloyd.com]brian(at)lloyd.com (brian(at)lloyd.com)[/url]

+1.767.617.1365 (Dominica)

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[b]

dabear(at)devere.us
Guest

Posted: Sat Dec 10, 2011 12:36 am Post subject: EGT

I would disagree with useless.  You cant use a laser temp gauge in the air… I had a “slight” engine roughness in the air, but not on the ground.  It would only happen at altitudes greater than 4k.  Turned out to be the wires to two cylinders going bad.  But I knew which ones, due to the EGT.  

I’ve had bad plug issues in the past, prior to the EGT that took a number of attempts to fix from good mechanics (not me).  Each recommended the EGT probes as the fastest way to know which cyl was giving us the problems.  

 

YMMV

 

Bear

 

From: owner-yak-list-server(at)matronics.com [mailto:owner-yak-list-server(at)matronics.com] On Behalf Of Genzlinger, Reade

Sent: Thursday, December 08, 2011 10:55 PM

To: yak-list(at)matronics.com

Subject: RE: EGT

 

A rough running engine will tell you all that too!  A simple check with a laser pyrometer ($80) will tell you which cylinder is cold on mag and plug issues. Primer and intake is easily identified by rough idle and visual cockpit check.   If you don’t have a way to lean the 9 probe egt is pretty useless.

 

Reade Genzlinger

Cairnwood Cooperative Corp.

215.914.0370



 

From: owner-yak-list-server(at)matronics.com (owner-yak-list-server(at)matronics.com) [mailto:owner-yak-list-server(at)matronics.com] ([email][mailto:owner-yak-list-server(at)matronics.com][/email]) On Behalf Of dabear(at)devere.us (dabear(at)devere.us)

Sent: Thursday, December 08, 2011 10:40 PM

To: yak-list(at)matronics.com (yak-list(at)matronics.com)

Subject: RE: EGT

 

So, yes, having the EGT readings can help if you have a bad plug or wire.  It can also tell you when you left the primer cocked over/open  and it can tell you when you left the intake drain open.  It immediately tells you when you have a Cyl problem.  I think it is worth the installation as it saves time/cost in troubleshooting problems.

 

Bear 	  Quote: 	
		      	
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  [quote][b]

brian(at)lloyd.com
Guest

Posted: Sat Dec 10, 2011 8:15 am Post subject: EGT

On Sat, Dec 10, 2011 at 12:33 AM,  <dabear(at)devere.us (dabear(at)devere.us)> wrote:

 	  Quote: 	
		   

I would disagree with useless.  



 	




A single-point EGT is useless. The only exception to that is a TIT but then you are measuring something else. 

 	  Quote: 	
		   

You cant use a laser temp gauge in the air… I had a “slight” engine roughness in the air, but not on the ground.  It would only happen at altitudes greater than 4k.  Turned out to be the wires to two cylinders going bad.  But I knew which ones, due to the EGT.   

I’ve had bad plug issues in the past, prior to the EGT that took a number of attempts to fix from good mechanics (not me).  Each recommended the EGT probes as the fastest way to know which cyl was giving us the problems.  



	




Yes, a probe-per-cylinder EGT is useful. But without a mixture control, it is substantially less useful. Sure it helped you in that case but you have to weigh the cost of troubleshooting the plug wires without EGT with the cost of the EGT. Of course your mechanic recommended it. There was no incremental cost to him. 

 



And then there is the point of knowing that your plug wires are more than 5 years old and should be replaced anyway. Plug wires and hoses. You know, one of the best ways to ensure that your airplane doesn't have problems while flying is to be aggressive on prophylactic maintenance. That substantially mitigates the need for diagnostic instrumentation.

 

-- 

Brian Lloyd, WB6RQN/J79BPL

3191 Western Dr.

Cameron Park, CA 95682

brian(at)lloyd.com (brian(at)lloyd.com)

+1.767.617.1365 (Dominica)

+1.916.877.5067 (USA)

 

  [quote][b]

n395v

Joined: 10 Jan 2006
Posts: 450

Posted: Sun Dec 11, 2011 6:13 am Post subject: Re: EGT

Not a 9 cylinder unit but interesting read relative to info to be obtained from CHT's/EGT's



http://www.buy-ei.com/Information/Pilots%20Manual.pdf

_________________
Milt

rijaeger(at)wausau.k12.wi
Guest

Posted: Sun Dec 11, 2011 10:00 am Post subject: EGT

Milt,

  

 That was very informative and helpful! THANKS SO MUCH!!

  

 Rico

  

 



 	  Quote: 	
		  >> "n395v" <airboss(at)bearcataviation.com> 12/11/2011 8:13 AM >>>

--> Yak-List message posted by: "n395v" <airboss(at)bearcataviation.com>
	




Not a 9 cylinder unit but interesting read relative to info to be obtained from CHT's/EGT's



]http://www.buy-ei.com/Information/Pilots%20Manual.pdf[/code]



--------

Milt





Read this topic online here:



http://forums.matronics.com/viewtopic.php?p=360668#360668



http://www.matronics.com/contributionhttp://www.matronics.com/Navigator?Yak-List

           - MATRONICS p;                       -Matt Dralle, ======





  [quote][b]

mark.bitterlich(at)navy.m
Guest

Posted: Sun Dec 11, 2011 1:18 pm Post subject: EGT

I've watched this comment thread for a little while now and I am going to add my 2 cents.    

 

The person who pays for the device, and who owns and flys the airplane is the ONLY person who makes the final decision  of what is "useless" and what is "worthwhile".   

 

 

Mark Bitterlich

 



________________________________



From: owner-yak-list-server(at)matronics.com on behalf of Brian Lloyd

Sent: Sat 12/10/2011 11:12 AM

To: yak-list(at)matronics.com

Subject: Re: EGT





On Sat, Dec 10, 2011 at 12:33 AM, <dabear(at)devere.us> wrote:

	I would disagree with useless.  

A single-point EGT is useless. The only exception to that is a TIT but then you are measuring something else. 

	You cant use a laser temp gauge in the air... I had a "slight" engine roughness in the air, but not on the ground.  It would only happen at altitudes greater than 4k.  Turned out to be the wires to two cylinders going bad.  But I knew which ones, due to the EGT.  



	I've had bad plug issues in the past, prior to the EGT that took a number of attempts to fix from good mechanics (not me).  Each recommended the EGT probes as the fastest way to know which cyl was giving us the problems. 

Yes, a probe-per-cylinder EGT is useful. But without a mixture control, it is substantially less useful. Sure it helped you in that case but you have to weigh the cost of troubleshooting the plug wires without EGT with the cost of the EGT. Of course your mechanic recommended it. There was no incremental cost to him. 



And then there is the point of knowing that your plug wires are more than 5 years old and should be replaced anyway. Plug wires and hoses. You know, one of the best ways to ensure that your airplane doesn't have problems while flying is to be aggressive on prophylactic maintenance. That substantially mitigates the need for diagnostic instrumentation.



-- 

Brian Lloyd, WB6RQN/J79BPL

3191 Western Dr.

Cameron Park, CA 95682

brian(at)lloyd.com

+1.767.617.1365 (Dominica)

+1.916.877.5067 (USA)

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