Janat83 Posted July 1, 2019 Author Report Posted July 1, 2019 9 minutes ago, Shadrach said: I think your a bit confused about the relationship between OAT and EGT. All other things being equal, higher OAT usually means lower EGT. My last two flights (June 30th) I climbed from 85°F at sea level I supposed that's why I had High CHT warning on climb out, but the flight that I had the high EGT issue was on 26th, 2nd flight from bottom and you may see how EGT is higher than all other flights. Quote
carusoam Posted July 1, 2019 Report Posted July 1, 2019 Great collection of data, Janat. Really well shared. One thing for sure... you are probably showing how well a carb distributes fuel. There are a few times where people discuss various things they have tried to help improve mixing the fuel and air... Those things include... throttle position vs the secondary fuel nozzle throttle plate air mixing carb heat for better vaporization carb temp to get a better view of what is happening... Improvements in data collecting going forwards... get more time during the run-up... each flight doesn’t have a very clear R,B,L,B pattern of the mags being checked. you can watch the display to see the EGTs rise fully and fall fully... It takes a few additional seconds... Mag checks are a useful step in providing info for the rest of the data collection exercise inflight mag checks are even better for adding diagnostic info... Anotating the info with notes vs general time are always helpful... start, run-up, T/O, climb, cruise, lean, descent, land, taxi... One interesting thing... Are you familiar with the auto enrichment function / secondary fuel nozzle in the carb? Do you have any FF indication? Knowing when the secondary fuel nozzle is opened and closed may be helpful to seeing your F-A ratio changes... PP thoughts only, not a mechanic. Best regards, -a- 1 Quote
Janat83 Posted July 1, 2019 Author Report Posted July 1, 2019 13 minutes ago, RLCarter said: Did you add fuel before taking off? Yes that was after stopping for fuel at PDX and continue to Seattle Quote
RLCarter Posted July 1, 2019 Report Posted July 1, 2019 2 minutes ago, Janat83 said: Yes that was after stopping for fuel at PDX and continue to Seattle Bad fuel? Quote
Janat83 Posted July 1, 2019 Author Report Posted July 1, 2019 4 minutes ago, RLCarter said: Bad fuel? I used the same fuel for the next day without adding any other fuel and didn't have that issue again. 1 Quote
Janat83 Posted July 1, 2019 Author Report Posted July 1, 2019 12 hours ago, carusoam said: Great collection of data, Janat. Really well shared. One thing for sure... you are probably showing how well a carb distributes fuel. There are a few times where people discuss various things they have tried to help improve mixing the fuel and air... Those things include... throttle position vs the secondary fuel nozzle throttle plate air mixing carb heat for better vaporization carb temp to get a better view of what is happening... Improvements in data collecting going forwards... get more time during the run-up... each flight doesn’t have a very clear R,B,L,B pattern of the mags being checked. you can watch the display to see the EGTs rise fully and fall fully... It takes a few additional seconds... Mag checks are a useful step in providing info for the rest of the data collection exercise inflight mag checks are even better for adding diagnostic info... Anotating the info with notes vs general time are always helpful... start, run-up, T/O, climb, cruise, lean, descent, land, taxi... One interesting thing... Are you familiar with the auto enrichment function / secondary fuel nozzle in the carb? Do you have any FF indication? Knowing when the secondary fuel nozzle is opened and closed may be helpful to seeing your F-A ratio changes... PP thoughts only, not a mechanic. Best regards, -a- Thank you very much for your input, it's very helpful and I keep learning, I'm going to take each of your points ,FF transducer is about to be installed this week. I'm not aware of the auto enrichment function / secondary fuel nozzle in the carb, I usually fly WOT after pulling the Throttle to show very slight change in MP I'm here to learn from you guys , and I thank you for your time. My mechanic said that he need to check mags wiring in first place to see if something wrong with it, I''ll let you know Thanks again Quote
Hank Posted July 1, 2019 Report Posted July 1, 2019 18 minutes ago, Janat83 said: Thank you very much for your input, it's very helpful and I keep learning, I'm going to take each of your points ,FF transducer is about to be installed this week. I'm not aware of the auto enrichment function / secondary fuel nozzle in the carb, I usually fly WOT after pulling the Throttle to show very slight change in MP I'm here to learn from you guys , and I thank you for your time. My mechanic said that he need to check mags wiring in first place to see if something wrong with it, I''ll let you know Thanks again You're doing that part right. That closes off the auto-enrichment circuit that sends extra fuel through when the throttle is Wide Open. I call this position "WOT-" because it's not quite WOT. This works well for our carbureted Mooneys. 3 Quote
kortopates Posted July 1, 2019 Report Posted July 1, 2019 I am not sure what you mean by "high" EGTs, what I do see is an elevated EGT3 at takeoff on the 2nd flight of 6/25. I'd want to to know what the FF was at takeoff to see if it was a bit depressed. Variation in FF at takeoff can explain the higher EGTs. Another is induction leakage. Unless you're engine is purring very smoothly at idle, I'd suggest pressure testing the induction system to find and eliminate any leakage which hurts mixture distribution from a little to a lot. Do you have the CHT alarm set on you EDM? I suggest you set it up the CHT alarm for 420F and treat it is as a real emergency once a cyl is getting that hot. But keep in mind its a 100x easier to keep CHTs cooler by not letting get that high. Unless obstacles require it, and especially with a long runway, accelerate to well over Vy by 10-20 kts as soon your in ground effect and they climb out with the higher IAS of Vy+ 10-20 kts as early in the climb as possible. This will go a long ways to keeping the CHTs cooler. Also avoid leaning till CHTs really come down with some altitude and you see EGTs getting pretty rich which looks like at about 1250-1300F from your data. Now that you have download capability with your monitor, I suggest you fly the Savvy Test profile. From your gami sweeps, even though it will show you have pretty poor mixture distribution you can still learn your cylinder rankings from leanest to richest, which will help you with leaning ROP since you want to lean by your leanest ROP. Plus the lean Mag test will provide good diagnostic data on your ignition system and show us if there is a mag issue. After you get some good baseline data, you can do like what Anthony suggested above to see if ever so slightly cracking the throttle position improves your mixture distribution. Or if you add Carb temp, you can try a bit of carb heat to see if that helps as well but with out carb temp probe it tends not to be repeatable. If so you'll, see it a tighter EGTs spread and should be able to confirm with a narrower gami spread. You don't actually want to see a MAP drop though when you crack throttle just enough to change the airflow, unless you don't get any improvement till you have to crack it that far. 1 Quote
Shadrach Posted July 1, 2019 Report Posted July 1, 2019 I would say that none of your EGTs seem outside the normal range for a normally aspirated Lycoming. My IO360 will peak in the 1500s on all but the highest and hottest days. I have not flown a carburetted bird in quite sometime. I don't know if you're doing anything with the throttle/mixture in the areas that I am pointing to below, but if you are, please don't do it anymore. The precipitous climb from CHTs in the healthy low 300 range to >450 will not yield long cylinder life. Be aware that cylinder head tensile strength is reduced to 50% of its room-temperature value at 400F, and to ~33% at 500F. Quote
Janat83 Posted July 1, 2019 Author Report Posted July 1, 2019 5 hours ago, kortopates said: I am not sure what you mean by "high" EGTs, what I do see is an elevated EGT3 at takeoff on the 2nd flight of 6/25. I'd want to to know what the FF was at takeoff to see if it was a bit depressed. Variation in FF at takeoff can explain the higher EGTs. Another is induction leakage. Unless you're engine is purring very smoothly at idle, I'd suggest pressure testing the induction system to find and eliminate any leakage which hurts mixture distribution from a little to a lot. Do you have the CHT alarm set on you EDM? I suggest you set it up the CHT alarm for 420F and treat it is as a real emergency once a cyl is getting that hot. But keep in mind its a 100x easier to keep CHTs cooler by not letting get that high. Unless obstacles require it, and especially with a long runway, accelerate to well over Vy by 10-20 kts as soon your in ground effect and they climb out with the higher IAS of Vy+ 10-20 kts as early in the climb as possible. This will go a long ways to keeping the CHTs cooler. Also avoid leaning till CHTs really come down with some altitude and you see EGTs getting pretty rich which looks like at about 1250-1300F from your data. Now that you have download capability with your monitor, I suggest you fly the Savvy Test profile. From your gami sweeps, even though it will show you have pretty poor mixture distribution you can still learn your cylinder rankings from leanest to richest, which will help you with leaning ROP since you want to lean by your leanest ROP. Plus the lean Mag test will provide good diagnostic data on your ignition system and show us if there is a mag issue. After you get some good baseline data, you can do like what Anthony suggested above to see if ever so slightly cracking the throttle position improves your mixture distribution. Or if you add Carb temp, you can try a bit of carb heat to see if that helps as well but with out carb temp probe it tends not to be repeatable. If so you'll, see it a tighter EGTs spread and should be able to confirm with a narrower gami spread. You don't actually want to see a MAP drop though when you crack throttle just enough to change the airflow, unless you don't get any improvement till you have to crack it that far. If you checked all my flights except the one taken on 2019-06-25 22:20 you'll find my EGT was in range of 1200-1300F on climb-out, while on that particular flight the EGT was in range of 1300-1400F (max 1440F), here's the link for that flight only https://savvyanalysis.com/flight/3282973/4ac55ee4-7d23-497d-8d70-4bbba1b52d98 My CHT alarm is set to 450F , usually on cool day my CHT get to 420-430 on CHT#4, my previous owner told me that CHT#4 reads 30 degrees higher because it's using the original sensor of the airplane rather than other 3 sensors, my POH says that 450-500 is not a warning range and I can only operate the engine for short period only, however I deal with nay CHT above 450 seriously and reduce MP, RPM and increase mixture to keep it low as you see in my other flights. Thank you for all your tips to cool the CHT I'll make sure to follow it on every flight, it's very useful. I do have Carb temp gauge, however I have never tried to use it in flight , if you can share with me the proper way to use it I'd highly appreciate it Fuel flow sensor will be installed this week hopefully and i'll try to upload another flight with all your useful tips Thank you all for your support. Quote
Janat83 Posted July 1, 2019 Author Report Posted July 1, 2019 5 hours ago, Shadrach said: I would say that none of your EGTs seem outside the normal range for a normally aspirated Lycoming. My IO360 will peak in the 1500s on all but the highest and hottest days. I have not flown a carburetted bird in quite sometime. I don't know if you're doing anything with the throttle/mixture in the areas that I am pointing to below, but if you are, please don't do it anymore. The precipitous climb from CHTs in the healthy low 300 range to >450 will not yield long cylinder life. Be aware that cylinder head tensile strength is reduced to 50% of its room-temperature value at 400F, and to ~33% at 500F. Thank you for your input, so the temperature rise you see was during take off, I usually climb WOT and full mixture, full prop at 2700rpm to 3500 before touching anything, usually then I'd slow the rpm to 2500 and lean the mixture to 150-200 ROP so the engine will run smooth (unless the CHT is high then I'll keep the mixture in ) and most of my climbs are at 110-120 mph unless terrain was an issue. my CHT4 used to be 30 degrees warmer on most flight stages (previous owner said it's because theey didn't change the sensor for CHT4 when the mechanic installed the JPI monitor). so how I can keep that rise in the CHT gradual and avoid the "precipitous climb" as you mentioned. thank you all for your inputs I'm learning from you all. Quote
Shadrach Posted July 2, 2019 Report Posted July 2, 2019 (edited) On 7/1/2019 at 7:28 PM, Janat83 said: Thank you for your input, so the temperature rise you see was during take off, I usually climb WOT and full mixture, full prop at 2700rpm to 3500 before touching anything, usually then I'd slow the rpm to 2500 and lean the mixture to 150-200 ROP so the engine will run smooth (unless the CHT is high then I'll keep the mixture in ) and most of my climbs are at 110-120 mph unless terrain was an issue. my CHT4 used to be 30 degrees warmer on most flight stages (previous owner said it's because theey didn't change the sensor for CHT4 when the mechanic installed the JPI monitor). so how I can keep that rise in the CHT gradual and avoid the "precipitous climb" as you mentioned. thank you all for your inputs I'm learning from you all. So the throttle stays all the way to the stop (not the just enough to move the MP gauge previously mentioned). Why are you leaning to 150-200ROP? Why not use the target EGT method (note the take off EGT at full throttle/full rich and lean to maintain that in the climb) 150-200 ROP is not a conservative climb setting at lower DAs. Edited July 2, 2019 by Shadrach Quote
Janat83 Posted July 2, 2019 Author Report Posted July 2, 2019 19 hours ago, Shadrach said: So the throttle stays all the way to the stop (not the just enough to move the MP gauge previously mentioned). Why are you leaning to 150-200ROP? Why not use the target EGT method (note the take off EGT at full throttle and lean to maintain that in the climb) 150-200 ROP is not a conservative climb setting at lower DAs. yes good point, I'll use the target EGT from now on. Quote
Janat83 Posted July 9, 2019 Author Report Posted July 9, 2019 Mooniacs! I want to thank you all for your support, My mechanic inspected my ignition system and found the problem in my ignition switch sometimes it's not connecting to Left Mags , he replaced the switch and inspected the p-leads and found a bad grounding and replaced it as well. the good thing about this post that I learned a lot from you guys about how to operate my engine the right way and how to read my engine data, I can't thank you enough about that. below is my latest flight engine chart, you can see how I didn't get any hot CHT or EGT on climb, also I used the target EGT technique and the engine is now running way smoother and efficient on climb. https://savvyanalysis.com/flight/3293978/fe4dd266-de75-48f6-b139-39ea2e8c5403 special thanks to @Shadrach @kortopates @Hank @carusoam @DXB @gsxrpilot @RogueOne @FloridaMan @Cyril Gibb you're all the best 4 Quote
carusoam Posted July 9, 2019 Report Posted July 9, 2019 Great follow-up, Janat! Nice Savvy data download too! Best regards, -a- 1 Quote
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