Peter Rejto Posted September 30, 2021 Report Posted September 30, 2021 Shortly after installing a left mag SureFly 5 months ago I discovered that my bottom #4 plug was oil soaked with a lead ball. At the annual this plug was dry and normal and compression was 76/80. I'm not suggesting that the Surefly is responsible for oil control in this cylinder, but I wonder if the right Slick mag is too retarded to keep this plug warm? My reasoning is as follows: At runup, 1700 RPM, the Surefly drops 50 RPM and the Slick 100 RPM, possibly a bit more. But, at 2300 RPM the SureFly doesn't drop at all, and the Slick drops 100 RPM. My Mooney Operations manual says I should not see a difference of more than 50 RPM. The zero drop of the Surefly seems to indicate to me that the engine is primarily firing from the Surefly at higher RPMs. The Surefly is setup for advance. I'm wondering if I should consider disabling this feature and/or advancing the Slick right mag? I've also thought that I could test this theory if I flew (over the airport) on just the right mag for a while. If I pull the plug and it's dry (or dryer) thaty might be "proof." I would appreciate some advice. Thanks, Peter Quote
mike_elliott Posted September 30, 2021 Report Posted September 30, 2021 HI Peter, how are you? Enjoying your new hangar home? You have indicated decent compression, which would indicate both the valves and compression rings sealing well. It does not indicate the intake valve oil seal's integrity however and oil could be coming from here. The lead balls indicate perhaps too rich of ops, particularly on ground ops or cyl temps under 280 in cruise, If this can be attributed to cruise ops, switching to a slightly longer reach plug or fine wire plugs should correct this. You could mess with the timing as you suggest, but the data plate is lord god of spark setting, be it good or bad. 2 Quote
N231BN Posted September 30, 2021 Report Posted September 30, 2021 If it makes you feel better you can turn off the advance on the surefly. Please don't advance the slick mag, the statement in the Mooney manual is obsolete with the installation of the surefly. Quote
PT20J Posted September 30, 2021 Report Posted September 30, 2021 4 hours ago, N231BN said: If it makes you feel better you can turn off the advance on the surefly. Please don't advance the slick mag, the statement in the Mooney manual is obsolete with the installation of the surefly. THIS^^^^^^ When advanced, the Surefly plug will indeed fire first because the Slick doesn’t advance. 100 Rpm drop is not unusual for Slicks - that’s what my new ones did. However, even though the engine-mag timing was dead on, the right one eventually increased to about 150 rpm drop because the internal timing (E-gap) changed and I had it IRAN’d after 200 hours. Now it’s back to 100 rpm drop. I doubt the mag has anything to do with plug issue. It’s the burning gases in the combustion chamber that heats the plugs, not the spark. Skip 1 Quote
Peter Rejto Posted September 30, 2021 Author Report Posted September 30, 2021 Many thanks for the responses! So much for my "theory!" I will need to investigate why I'm seeing this oil fouling on the plug. In any case the plug is firing because the engine doesn't stumble on a mag check at idle or higher power. I'll start by checking the lead resistance and progress from there. Peter 1 Quote
Ragsf15e Posted September 30, 2021 Report Posted September 30, 2021 36 minutes ago, Peter Rejto said: Many thanks for the responses! So much for my "theory!" I will need to investigate why I'm seeing this oil fouling on the plug. In any case the plug is firing because the engine doesn't stumble on a mag check at idle or higher power. I'll start by checking the lead resistance and progress from there. Peter You can still get a good compression with oil leaking in around the rings as the oil will help “seal” the cylinder during compression checks. How is your oil use? Does the oil get black quickly after change? Does the belly get “a lot” of oil on it? All signs of blow by the rings. Not the end of the world though. Definitely recommend leaning very aggressively on the ground immediately after start and after landing as that pretty much solves the lead buildup issue. 1 Quote
carusoam Posted October 1, 2021 Report Posted October 1, 2021 The oil ring is responsible for sealing oil from escaping the case, into the cylinders…. The compression rings are responsible for holding the combustion gasses in place… So the compression test, unfortunately, won’t say much about the oil ring… When valve guides wear… there is a seal up there that keeps the oil from coming down the valve stem… If you have an engine monitor… A really good run-up… can show the differences in mag timing…. Having a SureFly will probably show some differences as well… either way… the oil leak and timing have not been related… (that I’m familiar with) If a valve is getting loose… there is a test for that…. Look up the wobble test… Might be a good time to have a bore scope have a peek at the valves… If you get enough oil to leak into a cylinder… The spark plug can get pretty dirty. And… if it is only one cylinder… why not the the others? Hmmm…. Lead balls usually distribute themselves evenly with fuel distribution…. Follow the guidance on deep leaning on the ground usually limits the size and number of lead deposits…. If you don’t lean on the ground… The lead balls can get pretty big…. (Early O360 experience from NJ) PP thoughts only, not a mechanic… Best regards, -a- Quote
Peter Rejto Posted October 3, 2021 Author Report Posted October 3, 2021 (edited) Sorry, I did not check this thread for a few days as I got distracted with keeping up with information from Savvy after I sent in my EGT/CHT data. (also, for some reason I stopped getting email copies of responses to this thread.) Savvy thinks I have a manifold leak, however today after checking everything including the sniffle valve and spraying soapy water on the intake manifold gaskets, etc, nothing could be found leaking at all. However, I have now noticed that EGT on Cyl #1 is always higher, and is considerably higher running a lean mag check on the left Surefly mag. My next test will be to do the Gami peak fuel flow test. I won't be surprised if I discover a much larger spread than normal. Perhaps the #1 injector is dirty. Time will tell. Of course, I can't see how this has anything to do with my original post about the #4 bottom plug. That still remains a mystery...however, I will get it borescoped ASAP. Also, if I can locate a fine wire plug in Australia (so far I cannot!) I will try running it in the interim. I normally lean on the ground....this is a change from what I've seen from this engine since the Firewall Forward OH in 2006. I'm not showing any signs of increased oil consumption, no blowby, clean belly. But, something isn't happy down there. Peter Edited October 4, 2021 by Peter Rejto Quote
A64Pilot Posted October 3, 2021 Report Posted October 3, 2021 A low compression cylinder will run a higher EGT, sorry I haven’t followed the thread closely, but if this is the cylinder with the oil fouled plug,then it might just be worn. I guess I should ask how much considerably higher is Quote
Peter Rejto Posted October 4, 2021 Author Report Posted October 4, 2021 (edited) 15 hours ago, A64Pilot said: A low compression cylinder will run a higher EGT, sorry I haven’t followed the thread closely, but if this is the cylinder with the oil fouled plug,then it might just be worn. I guess I should ask how much considerably higher is The oil soaked bottom plug is in #4. The higher egt is from #1. You can see it in the plot attached which was from a ground run at 1700 RPM then 2100 RPM followed by a shutdown and restart with the sniffle valve tube blocked, also briefly checked right and left mags at 1700 rpm. The times are roughly as follows: ~ 3.5 min Leaned at 1700 rpm Left mag (Surefly) ~ 5.5 1700 rpm right mag ~7:00 leaned 2100 rpm Left ~9:00 2100 rpm right ~10:20 shut down blocked sniffle tube leaned 1700 rpm left ~13:10 1700 rpm right The red line is EGT #1 on top. It is always higher than the other egts, but gets hotter on just the left Surefly mag. CHT #3 is obviously not working but seems to be influencing CHT #1 somehow. The small rises on #1 seem to correspond to jumps on #3. Today I tested the #3 probe and leads and I have a good probe but bad leads which will be vexing to fix. I plan to retest with #3 disconnected. Hopefully #1 will not e jumpy, but why it is so much lower than the other CHTs is not evident. At 3.5 minutes #1=1412 , #2 1301, #3 1296 #4 1326 at 1700 rpm on Surefly. At 6.5 minutes #1=1346, #2 1345, #3 1305 #4 1305 at 1700 rpm on right mag Peter Edited October 4, 2021 by Peter Rejto Quote
carusoam Posted October 5, 2021 Report Posted October 5, 2021 Next time… Lets start with the data! Notice how nicely the EGTs are all playing nice…. If EGT3 was behaving poorly we would be looking at things going on inside the cylinder… CHT3 has gone nuts from the moment the engine has come to life… then goes through a sawtooth pattern… That is not reality… See if you can swap a neighboring CHT sensor and start the engine again… If the problem follows the sensor… bingo! See if Paul is around… @kortopates This looks more like a funky sensor grounding challenge… PP thoughts only, not a mechanic… Best regards, -a- Quote
Peter Rejto Posted October 6, 2021 Author Report Posted October 6, 2021 After a lot of fussing around I managed to swap a good probe to the CHT#3 input and the problem vanished. Also, I put the bad probe into input #2 and the problem followed the probe. What remains is a mystery: Why is CHT#1 so low? It tracks well until ~ 200F then falls behind. I am now inclined to get rid of my UBG-16. The data rate is way too slow. I was thinking of adding FF and new probes, but in the end it won't be fast enough. I want to keep the same 2.25" mounting as the UBG-16, so I think I'm limited to the EDM 700/800 or Insight G2/3 systems. Am I correct that the EDMs max out at a 2 sec rate? If so, the G3 is faster and perhaps a bit lower in cost. I know the G3 doesn't have a normalizing function. That wouldn't be a deal breaker for me if alarms are set properly. Have I missed a product that wouldn't necessitate a major panel disturbance and hemorrhaging more $$$$$? Peter Quote
Will.iam Posted October 6, 2021 Report Posted October 6, 2021 6 minutes ago, Peter Rejto said: After a lot of fussing around I managed to swap a good probe to the CHT#3 input and the problem vanished. Also, I put the bad probe into input #2 and the problem followed the probe. What remains is a mystery: Why is CHT#1 so low? It tracks well until ~ 200F then falls behind. I am now inclined to get rid of my UBG-16. The data rate is way too slow. I was thinking of adding FF and new probes, but in the end it won't be fast enough. I want to keep the same 2.25" mounting as the UBG-16, so I think I'm limited to the EDM 700/800 or Insight G2/3 systems. Am I correct that the EDMs max out at a 2 sec rate? If so, the G3 is faster and perhaps a bit lower in cost. I know the G3 doesn't have a normalizing function. That wouldn't be a deal breaker for me if alarms are set properly. Have I missed a product that wouldn't necessitate a major panel disturbance and hemorrhaging more $$$$$? Peter Peter i just sent off my edm-700 to get FF added to the unit. I also asked if they could increase the sampling rate and they said sure. Supposedly my unit will be able to record in one- second intervals now. I will let you know if that is true or not whenever i finally get my plane back from annual. Quote
Ragsf15e Posted October 6, 2021 Report Posted October 6, 2021 7 minutes ago, Peter Rejto said: After a lot of fussing around I managed to swap a good probe to the CHT#3 input and the problem vanished. Also, I put the bad probe into input #2 and the problem followed the probe. What remains is a mystery: Why is CHT#1 so low? It tracks well until ~ 200F then falls behind. I am now inclined to get rid of my UBG-16. The data rate is way too slow. I was thinking of adding FF and new probes, but in the end it won't be fast enough. I want to keep the same 2.25" mounting as the UBG-16, so I think I'm limited to the EDM 700/800 or Insight G2/3 systems. Am I correct that the EDMs max out at a 2 sec rate? If so, the G3 is faster and perhaps a bit lower in cost. I know the G3 doesn't have a normalizing function. That wouldn't be a deal breaker for me if alarms are set properly. Have I missed a product that wouldn't necessitate a major panel disturbance and hemorrhaging more $$$$$? Peter I have an F, so the cowling is a little different, but it’s pretty common for the #1 CHT to be a little lower than the others just based on where it sits and how much airflow it gets. I’m sure everyone isn’t the same, but I generally see ~350 in cruise on #3, while #1 shows something like 290. The EGTs are similar between all 4 cylinders. Quote
carusoam Posted October 7, 2021 Report Posted October 7, 2021 Peter, Congrats on finding the sensor challenge… There are four really good engine monitors to consider… The 90s technology was pretty good with a max of 2sec intervals… Most things today use 1sec because memory isn’t as limited lately… When doing a run-up, the faster data acquisition is really helpful… 1) EI Electronics International… really good, not as popular…. 2) JPI.. really popular, not as good… 3) Insight… some models are too long to fit… owners really like them… 4) Garmin EIS. A huge flight info gathering and engine monitor device…. Really new, and getting included with other G big screen TVs…. Got a pic of the latest graph showing the CHT maxing out on one cylinder? Pp thoughts only, not a monitor guy… Best regards, -a- Quote
Peter Rejto Posted October 7, 2021 Author Report Posted October 7, 2021 Thanks for your ranking of monitors! I'm becoming inclined to possibly go with one of the EI units...the CGR-30P. It's 3.25" but will actually fit in the same location as my UBG-16. The good thing is that I can retain a lot of my existing installation. I do like the EDM 830 but it's just slightly too large to fit without really messing with the panel. The bad part of the CGR is the long ordering time to get one, not too mention slow shipping to Australia. Best regards, Peter Quote
carusoam Posted October 7, 2021 Report Posted October 7, 2021 Peter, For tough EI questions…. We have a guy! Find @oregon87…. He was just here answering questions about piggyback sensors… Some MSers go with a pair for the EI round displays… I think the pair has all the primary gauges to eliminate some of the old ones on the panel… Pp thoughts only, not a mechanic… Best regards, -a- Quote
bmcconnaha Posted October 7, 2021 Report Posted October 7, 2021 (edited) 30 minutes ago, Peter Rejto said: Thanks for your ranking of monitors! I'm becoming inclined to possibly go with one of the EI units...the CGR-30P. It's 3.25" but will actually fit in the same location as my UBG-16. The good thing is that I can retain a lot of my existing installation. I do like the EDM 830 but it's just slightly too large to fit without really messing with the panel. The bad part of the CGR is the long ordering time to get one, not too mention slow shipping to Australia. Best regards, Peter we sell both JPI and EI... both fine units. i like talking to EI better for support. EI also has a trade in rebate for trading one of their old units. PM me if i can help with pricing @Peter Rejto Edited October 7, 2021 by bmcconnaha 1 1 Quote
skykrawler Posted October 22, 2021 Report Posted October 22, 2021 On 9/30/2021 at 7:49 AM, mike_elliott said: snip........ It does not indicate the intake valve oil seal's integrity however and oil could be coming from here. ...... I don't think Lycoming's -360 have intake valve seals, so that isn't the problem. Quote
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