lithium366 Posted December 23, 2019 Report Share Posted December 23, 2019 Had a blast long cross country flight from Burbank to Houston yesterday. For the last 3 hours I observed that #1 cyl EGT sporadically goes down. Like jumping between 1200-1300 in cruse every second while normally 1400. To me that sounds like a failing probe because otherwise engine is running smooth but I will appreciate any advise before I go on a 8 hours flight back. Engine is IO-360-A1A on a M20E Quote Link to comment Share on other sites More sharing options...
Guitarmaster Posted December 23, 2019 Report Share Posted December 23, 2019 https://photos.app.goo.gl/TyMPfZ7QCtJhWdKT6Does it look like this?Sent from my Pixel 2 XL using Tapatalk Quote Link to comment Share on other sites More sharing options...
lithium366 Posted December 23, 2019 Author Report Share Posted December 23, 2019 28 minutes ago, Guitarmaster said: https://photos.app.goo.gl/TyMPfZ7QCtJhWdKT6 Does it look like this? Sent from my Pixel 2 XL using Tapatalk Not sure how to read yours but if I understand correctly you have elevated EGT on #6 and #4 cylinders. If so then I have an opposite picture when one of the cylinders EGT is significantly lower than other 3 (and than that particular cylinder 5 hours ago) Quote Link to comment Share on other sites More sharing options...
Guitarmaster Posted December 23, 2019 Report Share Posted December 23, 2019 Not sure how to read yours but if I understand correctly you have elevated EGT on #6 and #4 cylinders. If so then I have an opposite picture when one of the cylinders EGT is significantly lower than other 3 (and than that particular cylinder 5 hours ago) It's actually a video, if you play it, you will see the number 6 EGT on the left engine bouncing around. If this is kind of what you're experiencing, I would say without a doubt it's a probe.Sent from my Pixel 2 XL using Tapatalk Quote Link to comment Share on other sites More sharing options...
lithium366 Posted December 23, 2019 Author Report Share Posted December 23, 2019 1 minute ago, Guitarmaster said: It's actually a video, if you play it, you will see the number 6 EGT on the left engine bouncing around. If this is kind of what you're experiencing, I would say without a doubt it's a probe. Sent from my Pixel 2 XL using Tapatalk Yes, kind of similar behaviour Quote Link to comment Share on other sites More sharing options...
carusoam Posted December 24, 2019 Report Share Posted December 24, 2019 Great video Matt! Ilya, the EGT sensors are the most susceptible to wear because of the high temp they are sitting in... They are pretty easy to pull out and visually inspect or test for accuracy in a glass of water, and a pot of boiling water... dirty and loose connections are next on the list... these sensors don’t typically go bad like a TIT sensor can... EGTs get a lot of time off between waves of exhaust... where the TIT gauge sees heat waves from every exhaust stream provided by the engine.... PP thoughts only, best regards, -a- 2 Quote Link to comment Share on other sites More sharing options...
DXB Posted December 24, 2019 Report Share Posted December 24, 2019 On 12/23/2019 at 12:16 PM, lithium366 said: Had a blast long cross country flight from Burbank to Houston yesterday. For the last 3 hours I observed that #1 cyl EGT sporadically goes down. Like jumping between 1200-1300 in cruse every second while normally 1400. To me that sounds like a failing probe because otherwise engine is running smooth but I will appreciate any advise before I go on a 8 hours flight back. Engine is IO-360-A1A on a M20E Also before you replace the EGT probe, tighten its connector to the harness after coating contact with Stabilant22. That worked for me once. 1 Quote Link to comment Share on other sites More sharing options...
lithium366 Posted December 30, 2019 Author Report Share Posted December 30, 2019 Here it is on the way back: https://youtu.be/A8BLq0lTpKY Quote Link to comment Share on other sites More sharing options...
Yetti Posted December 30, 2019 Report Share Posted December 30, 2019 I vote wiring harness. Take pictures under the cowl and we will be happy to point out things that are wrong. 1 Quote Link to comment Share on other sites More sharing options...
Marauder Posted December 30, 2019 Report Share Posted December 30, 2019 Here it is on the way back: Check the connection between the probe and the harness. I have seen similar issues. Just follow the probe until you get to a fire sleeve. It’s under there. Sent from my iPhone using Tapatalk Pro 1 Quote Link to comment Share on other sites More sharing options...
Prior owner Posted December 30, 2019 Report Share Posted December 30, 2019 Mine is doing the exact same thing...strangely, also on cyl #1. Weird. But I was just in there installing an Airwolf oil/air separator, so I am guessing that I inadvertently mucked up a wire on the harness. Quote Link to comment Share on other sites More sharing options...
Browncbr1 Posted December 30, 2019 Report Share Posted December 30, 2019 (edited) On 12/23/2019 at 12:16 PM, lithium366 said: Had a blast long cross country flight from Burbank to Houston yesterday. For the last 3 hours I observed that #1 cyl EGT sporadically goes down. Like jumping between 1200-1300 in cruse every second while normally 1400. To me that sounds like a failing probe because otherwise engine is running smooth but I will appreciate any advise before I go on a 8 hours flight back. Engine is IO-360-A1A on a M20E If you are running LOP, that could be a partially blocked injector. Easy to pull injector and soak in hopps or mek.. worth checking. Sometimes, this can happen after switching tanks, as the fuel valve van collect debris. I suggest doing this every annual: pull injectors, soak, and while they are soaking do the Dixie cups test while twisting the fuel valve back and forth from tank to tank rapidly to see if any debris comes out. Continue until clear. Do this before cleaning gascolator. Edited December 30, 2019 by Browncbr1 Quote Link to comment Share on other sites More sharing options...
Tcraft938 Posted December 30, 2019 Report Share Posted December 30, 2019 Is the CHT for the cylinder reasonably similar to the others and stay pretty steady in cruise? Quote Link to comment Share on other sites More sharing options...
Prior owner Posted December 30, 2019 Report Share Posted December 30, 2019 48 minutes ago, Tcraft938 said: Is the CHT for the cylinder reasonably similar to the others and stay pretty steady in cruise? My CHT is staying relatively constant in cruise. Only the EGT is moving up and down. Quote Link to comment Share on other sites More sharing options...
lithium366 Posted January 1, 2020 Author Report Share Posted January 1, 2020 On 12/30/2019 at 10:29 AM, PilotCoyote said: My CHT is staying relatively constant in cruise. Only the EGT is moving up and down. Same for me. Quote Link to comment Share on other sites More sharing options...
lithium366 Posted January 1, 2020 Author Report Share Posted January 1, 2020 On 12/30/2019 at 9:24 AM, Browncbr1 said: If you are running LOP, that could be a partially blocked injector. Easy to pull injector and soak in hopps or mek.. worth checking. Sometimes, this can happen after switching tanks, as the fuel valve van collect debris. I suggest doing this every annual: pull injectors, soak, and while they are soaking do the Dixie cups test while twisting the fuel valve back and forth from tank to tank rapidly to see if any debris comes out. Continue until clear. Do this before cleaning gascolator. I am running ROP. Do you think injectors can cause these jumps in numbers? Quote Link to comment Share on other sites More sharing options...
Guitarmaster Posted January 1, 2020 Report Share Posted January 1, 2020 I am running ROP. Do you think injectors can cause these jumps in numbers? A plugged injector will make the cylinder run lean. You would see an increase in egt but it would be steady.All your other numbers are normal. Look for what doesn't fit. Sent from my Pixel 2 XL using Tapatalk 1 Quote Link to comment Share on other sites More sharing options...
Browncbr1 Posted January 1, 2020 Report Share Posted January 1, 2020 (edited) 9 hours ago, lithium366 said: I am running ROP. Do you think injectors can cause these jumps in numbers? A partially blocked injector can cause unstable egt, causing the cylinder to go leaner. Ive also experienced similar symptoms due to corrosion on the end of the spring of a spark plug harness lead where it fits inside the plug. I scraped and cleaned up inside the plug and the harness spring and it solved the issue. But on this one, it was easy to see with an inflight lop mag check. Egt was unstable and non rhythmic.. Edited January 1, 2020 by Browncbr1 Quote Link to comment Share on other sites More sharing options...
M20F Posted January 1, 2020 Report Share Posted January 1, 2020 On 12/24/2019 at 2:13 PM, DXB said: Also before you replace the EGT probe, tighten its connector to the harness after coating contact with Stabilant22. That worked for me once. I second this. I recently pulled a CHT probe, put the new one on, went to detach the wire that leads to cockpit, noticed said connector was detached..... Quote Link to comment Share on other sites More sharing options...
carusoam Posted January 1, 2020 Report Share Posted January 1, 2020 Getting an EGT to oscillate in a random fashion would require a piece of FOD to be swirling around in or near the FI... Sometimes blocking flow, sometimes not blocking flow... This would be on the less likely end of the spectrum than what is often report for things that block fuel injectors... PP thoughts only, not a mechanic... Best regards, -a- Quote Link to comment Share on other sites More sharing options...
Prior owner Posted January 1, 2020 Report Share Posted January 1, 2020 Fixed mine today- it was a bad connection at the probe 2 Quote Link to comment Share on other sites More sharing options...
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