Yetti Posted April 13, 2016 Report Share Posted April 13, 2016 The company I work for is a software company that creates software that sits on top of control systems such as SCADA, DCS and the like. We historize and visualize the data from the underlying systems. We can also look for events in the data and then notify for out of range events. I just read a facebook post on how the person's #3 valve stuck open. The causes of sticky valves are known. Bad Lycoming design for oil delivery to the guide shafts, coking of the oil, wobble test, rope trick, conditions the engine is operated under, reaming of the valve guides to remove the coked oil. (Yes I got the chance to see a valve hammered out with a punch and hammer and then got to ream the guide) So will an engine monitor and a historization of the data show that a valve is about to stick, or come apart prior to the event happening? Would the user of the engine monitor know what the monitor is telling them to know? If the engine monitor can tell, then what does it not pop up a message that says. "hey just wanted to let you know valve 3 is getting sticky and at some point could stick fully open" Quote Link to comment Share on other sites More sharing options...
mooniac15u Posted April 13, 2016 Report Share Posted April 13, 2016 The guys at Savvy Analysis claim they can tell ahead of time. https://www.savvyanalysis.com/content/feva/ Quote Link to comment Share on other sites More sharing options...
FloridaMan Posted April 13, 2016 Report Share Posted April 13, 2016 I believe that Insight's latest engine monitors do analysis and will alert a user to a potential valve issue. With that said, I believe that JPI and EI have the majority of market share. Mike Busch's site ( http://www.savvyaviator.com/ ) offers a service that performs in-depth engine monitor log analysis as well. I am very happy with my JPI EDM-900. Keep in mind there are other things than a failed valve that can cause an engine failure. Mine failed at 200ft on takeoff due to FOD. On landing, both plugs in the #4 cylinder were discovered to be destroyed; however, the symptom was more like a stuck valve. My theory was that the FOD may have jammed into the valve first and did the damage after I cut what was left of the power. The nice thing, in hindsight, about the detailed engine monitor data, is that I knew that if I hadn't invested in the engine monitor that I would have been remorseful about not having an engine monitor, that maybe it could have alerted me. The logs showed no symptom of an imminent failure. Quote Link to comment Share on other sites More sharing options...
ArtVandelay Posted April 13, 2016 Report Share Posted April 13, 2016 2 minutes ago, mooniac15u said: The guys at Savvy Analysis claim they can tell ahead of time. https://www.savvyanalysis.com/content/feva/ I believe thats a failed valve they claim to be able diagnose, not a stuck valve. Quote Link to comment Share on other sites More sharing options...
Yetti Posted April 13, 2016 Author Report Share Posted April 13, 2016 Usually I work the problem this way. What is the top ten list of inflight engine issues? Once you have those you search for events or indicators that foretell of the most common failures (sad thing is you have to be recording and have stored the data and then have the failure) Now you have the way be predictive and you can alert and notify of conditions BEFORE the failure. Quote Link to comment Share on other sites More sharing options...
jetdriven Posted April 13, 2016 Report Share Posted April 13, 2016 Lycomings get "morning sickness" before they stick a valve. Listen to your engine 2 Quote Link to comment Share on other sites More sharing options...
PTK Posted April 13, 2016 Report Share Posted April 13, 2016 I would think a stuck valve would show up as no CHT and relatively normal EGT. A stuck valve prevents the affected cylinder from making power but it's still getting fuel and spark plug is firing. Quote Link to comment Share on other sites More sharing options...
Yetti Posted April 13, 2016 Author Report Share Posted April 13, 2016 12 minutes ago, jetdriven said: Lycomings get "morning sickness" before they stick a valve. Listen to your engine This is not something that is taught in Primary flight training..(neither is changing the Engine oil, but we can do that after we get a PPL) What do you think the number of pilots that know what morning sickness sounds like? On some threads I have read that the morning sickness is done by the time the engine monitor boots up Quote Link to comment Share on other sites More sharing options...
Bob_Belville Posted April 13, 2016 Report Share Posted April 13, 2016 Just now, Yetti said: This is not something that is taught in Primary flight training..(neither is changing the Engine oil, but we can do that after we get a PPL) What do you think the number of pilots that know what morning sickness sounds like? On some threads I have read that the morning sickness is done by the time the engine monitor boots up My EDM 930 is "booted up" before the engine is started. Quote Link to comment Share on other sites More sharing options...
wishboneash Posted April 13, 2016 Report Share Posted April 13, 2016 I think the EGT would be out of whack with a sticky valve. CHTs are much slower to respond at start up. What I had noticed was during start up with morning sickness, one cylinder would come up with a very low EGT for 30sec or so. 1 Quote Link to comment Share on other sites More sharing options...
rbridges Posted April 13, 2016 Report Share Posted April 13, 2016 1 minute ago, Yetti said: This is not something that is taught in Primary flight training..(neither is changing the Engine oil, but we can do that after we get a PPL) What do you think the number of pilots that know what morning sickness sounds like? On some threads I have read that the morning sickness is done by the time the engine monitor boots up I was going to ask the same thing. Someone mentioned something to me, but I checked my engine monitor logs and saw nothing. I've also listened to the engine from inside the cockpit during a cold start and couldn't tell. I was wondering if I heard it but didn't know it. Quote Link to comment Share on other sites More sharing options...
Yetti Posted April 13, 2016 Author Report Share Posted April 13, 2016 Does morning sickness and a fouled plug sound the same? Can the engine monitor tell the difference between a sticky valve and a fouled plug? Quote Link to comment Share on other sites More sharing options...
rbridges Posted April 13, 2016 Report Share Posted April 13, 2016 Just throwing this out there, so correct me if I'm wrong. Since you have 2 plugs, a fouled plug only results in slightly lower temps. A stuck exhaust valve should have a much lower temp because you're basically shutting that cylinder down since you only have a single exhaust valve. Quote Link to comment Share on other sites More sharing options...
N601RX Posted April 13, 2016 Report Share Posted April 13, 2016 When I had a stuck valve the egt spiked briefly for a second or two and then fell sharply toward zero. When reaming a valve, special reamers are available that have a properly sized pilot so the reamer stays centered and only removes carbon. These are available from Mcfarland. If you use a reamer that is designed for guide replacement and reaming new guides the pilot is going to be too small the properly support the reamer in the hole. The valve wizard works very well for removing the springs, no rope or air pressure was even needed. It keeps both your hands free and allows small changes in spring compression. With practice wobble can be measured in under an hr per cylinder and add an extra hr if it needs reaming. If a regular member needs these tools I will rent them at a very reasonable rate. I had to purchase them, but will not use them very often. They are only for angle valve cylinders. Video.MOV 1 Quote Link to comment Share on other sites More sharing options...
N201MKTurbo Posted April 13, 2016 Report Share Posted April 13, 2016 25 minutes ago, rbridges said: Just throwing this out there, so correct me if I'm wrong. Since you have 2 plugs, a fouled plug only results in slightly lower temps. A stuck exhaust valve should have a much lower temp because you're basically shutting that cylinder down since you only have a single exhaust valve. A fouled plug will show up as an increase in EGT and a decrease in CHT. It effectively changes your timing to a more retarded timing because the charge is being lit from a single point instead of two the flame front has to burn twice as far to burn all the charge. This leaves more heat in the charge when the valve opens that raises the EGT and gives less time for the heat to transfer to the head reducing the CHT. Quote Link to comment Share on other sites More sharing options...
Yetti Posted April 13, 2016 Author Report Share Posted April 13, 2016 Quote Link to comment Share on other sites More sharing options...
Yetti Posted April 13, 2016 Author Report Share Posted April 13, 2016 I think we are coming to one of my current themes. It is great to have data and have it presented to you. Changing data into information is the hard part. There seems to be a fair amount of people with fancy engine monitors, but don't know what the data is saying to them. The engine monitor should see High EGT and decrease CHT and say "hey buddy you might have a fouled plug on cynd #3" Quote Link to comment Share on other sites More sharing options...
rbridges Posted April 13, 2016 Report Share Posted April 13, 2016 Just now, Yetti said: I think we are coming to one of my current themes. It is great to have data and have it presented to you. Changing data into information is the hard part. There seems to be a fair amount of people with fancy engine monitors, but don't know what the data is saying to them. The engine monitor should see High EGT and decrease CHT and say "hey buddy you might have a fouled plug on cynd #3" true but good luck getting an STC for that. Quote Link to comment Share on other sites More sharing options...
Yetti Posted April 13, 2016 Author Report Share Posted April 13, 2016 Just now, rbridges said: true but good luck getting an STC for that. spoil sport. There is already a USB port on the engine monitor. Hook that up to a Raspberry PI and have the Raspberry PI running analytical software that notifies and provides the pilot with real time information based on the analytic. 1 Quote Link to comment Share on other sites More sharing options...
N201MKTurbo Posted April 13, 2016 Report Share Posted April 13, 2016 Pretty soon there wont be anything for us to do! We will have to install a horn that wakes us up when it is time to get out of the plane.... 2 Quote Link to comment Share on other sites More sharing options...
ArtVandelay Posted April 13, 2016 Report Share Posted April 13, 2016 3 hours ago, wishboneash said: I think the EGT would be out of whack with a sticky valve. CHTs are much slower to respond at start up. What I had noticed was during start up with morning sickness, one cylinder would come up with a very low EGT for 30sec or so. This what morning sickness (i think, im only a PP) looks like on my engine monitor, whether its a stuck valve or clogged fuel injector I don't think there is a way to tell. 2 Quote Link to comment Share on other sites More sharing options...
rbridges Posted April 13, 2016 Report Share Posted April 13, 2016 thanks for the picture. Now I have an idea of what to expect. Quote Link to comment Share on other sites More sharing options...
N601RX Posted April 13, 2016 Report Share Posted April 13, 2016 Here is one that stuck briefly in flight. The EGT spiked briefly and they the cylinder dropped out. The other egt's dropped because I moved the mixture to full rich. Quote Link to comment Share on other sites More sharing options...
ArtVandelay Posted April 13, 2016 Report Share Posted April 13, 2016 20 minutes ago, N601RX said: Here is one that stuck briefly in flight. The EGT spiked briefly and they the cylinder dropped out. The other egt's dropped because I moved the mixture to full rich. But how do you tell the difference between a stuck valve and clogged injector? Would the fuel flow change or would it remain the same, the other cylinders becoming richer? Quote Link to comment Share on other sites More sharing options...
flyboy0681 Posted April 13, 2016 Report Share Posted April 13, 2016 (edited) 5 hours ago, Yetti said: So will an engine monitor and a historization of the data show that a valve is about to stick, or come apart prior to the event happening? I believe this is what you are looking for.. AE-35Failure_1_.wav Edited April 13, 2016 by flyboy0681 1 Quote Link to comment Share on other sites More sharing options...
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