carusoam Posted May 25, 2021 Report Posted May 25, 2021 Rags, Is that your blue stain? For a better look, this may help... See if @M20Doccan have a look at that... See if the other bolt is still in place... PP thoughts only... Best regards, -a- Quote
Guest Posted May 25, 2021 Report Posted May 25, 2021 A bad intake gasket or a crack in the bend at the end of the tube are possibilities. Clarence Quote
Ragsf15e Posted May 25, 2021 Report Posted May 25, 2021 5 hours ago, M20Doc said: A bad intake gasket or a crack in the bend at the end of the tube are possibilities. Clarence Yep, thanks Doc. Hoping to get it in tomorrow with my mechanic. That cylinder/intake connection have always had a little “seepage” the whole time I’ve had the airplane. We had two gaskets on for a while and it helped. Right now the gasket looks compressed/pinched-in right behind the oil line where you can’t see. Quote
Yetti Posted May 25, 2021 Report Posted May 25, 2021 I vote for a loose MP sensor or something like that. Quote
carusoam Posted May 26, 2021 Report Posted May 26, 2021 Want to share some JPI data? See if we can ‘see’ the leak in the data? Best regards, -a- Quote
MikeOH Posted May 26, 2021 Report Posted May 26, 2021 4 minutes ago, carusoam said: Want to share some JPI data? See if we can ‘see’ the leak in the data? Best regards, -a- I can 'see' the leak in the photo! What, exactly, will JPI data add to the situation? Quote
carusoam Posted May 26, 2021 Report Posted May 26, 2021 2 minutes ago, MikeOH said: I can 'see' the leak in the photo! What, exactly, will JPI data add to the situation? when fuel is leaking out of the intake... There is a similar flow of extra air into that cylinder... I think the OP mentioned that the EGTs didn’t indicate a leak... But, I expect that the EGT on that cylinder my stand a few degrees taller than the rest... Probably not enough to say... hey look at this problem.... more of... hey there is this problem... and I see it matching in the graph... Some JPI graph readers are really good... it is possible that the EGT is obviously out of line to that person... Hence the request... can we see the data? It might be revealing... or it might not be... I’m hoping I can see something... Our JPI monitors are that good... Best regards, -a- Quote
Guest Posted May 26, 2021 Report Posted May 26, 2021 19 hours ago, Ragsf15e said: Yep, thanks Doc. Hoping to get it in tomorrow with my mechanic. That cylinder/intake connection have always had a little “seepage” the whole time I’ve had the airplane. We had two gaskets on for a while and it helped. Right now the gasket looks compressed/pinched-in right behind the oil line where you can’t see. The intake flange gaskets tend to last about 500 hours before they dry out and crack. The Continental (AEL part number) are a bit thicker than the Lycoming version. Clarence Quote
PT20J Posted May 26, 2021 Report Posted May 26, 2021 If it has always been an issue and two gaskets didn’t fix it, perhaps something isn’t square. Quote
Ragsf15e Posted May 26, 2021 Report Posted May 26, 2021 58 minutes ago, PT20J said: If it has always been an issue and two gaskets didn’t fix it, perhaps something isn’t square. As doc mentioned, the gasket was dried out. No cracks, so that’s good. We did lap the flange, so it’s square. How come nobody told me how much of a PIA it was going to be to access the back bolt on the riser?! Wtf?! It took unhooking the oil return, loosening all the metal baffles and prying them back and then shoving a socket up there! #1 would have been much easier. Carusam, ill try to post some egt data, but I don’t think you’ll see it. 1 1 Quote
Ragsf15e Posted May 26, 2021 Report Posted May 26, 2021 13 hours ago, carusoam said: when fuel is leaking out of the intake... There is a similar flow of extra air into that cylinder... I think the OP mentioned that the EGTs didn’t indicate a leak... But, I expect that the EGT on that cylinder my stand a few degrees taller than the rest... Probably not enough to say... hey look at this problem.... more of... hey there is this problem... and I see it matching in the graph... Some JPI graph readers are really good... it is possible that the EGT is obviously out of line to that person... Hence the request... can we see the data? It might be revealing... or it might not be... I’m hoping I can see something... Our JPI monitors are that good... Best regards, -a- Here you go, not sure if you'll see anything. There are 3 screen shots - taxi to maintenance before fixing it, taxi back to the hangar, and leaning in flight on the last flight before maint. I suspect if there's anything to see it's in the taxi since the MP is pulled way back. I couldn't see anything. Taxi Before: Taxi After: Leaning In Flight: 1 Quote
MikeOH Posted May 27, 2021 Report Posted May 27, 2021 22 hours ago, carusoam said: when fuel is leaking out of the intake... There is a similar flow of extra air into that cylinder... I think the OP mentioned that the EGTs didn’t indicate a leak... But, I expect that the EGT on that cylinder my stand a few degrees taller than the rest... Probably not enough to say... hey look at this problem.... more of... hey there is this problem... and I see it matching in the graph... Some JPI graph readers are really good... it is possible that the EGT is obviously out of line to that person... Hence the request... can we see the data? It might be revealing... or it might not be... I’m hoping I can see something... Our JPI monitors are that good... Best regards, -a- @carusoam Sorry to be dense, but I'm just not seeing the point of analyzing engine monitor data. We KNOW there is a problem with the sealing between the manifold and the head as evidenced by the dramatic blue stains. Of what use is revealing altered EGTs, or even CHTs? What would be done differently to fix the issue if you see something in the data versus not seeing anything? Either way, the leak needs to be fixed. In other words, I can't see how the data is going to point you to a more specific location for the leak than what is already evident. I love engine monitor data as much as the next guy, but in this case I'm not comprehending what it brings to the table??? Enlighten me, please. 1 Quote
N201MKTurbo Posted May 27, 2021 Report Posted May 27, 2021 On 5/24/2021 at 5:01 PM, Ragsf15e said: So before your intake riser came off, did it look like this? The injector above is dry and clean, I think this is coming out the intake gasket. My gami spread is great, but it seems there’s an intake leak here? No, it looked normal. If that fuel is coming out of your intake, it would come out of your drain line anyway. I bet it is coming out of your injector and dripping through your fins and evaporating on your pipe. Quote
carusoam Posted May 27, 2021 Report Posted May 27, 2021 Mike there is a lot going on in an engine... the monitor often tells some of it... Some people can really read the graphs and data... and get something of value out of it... If you can’t see it, or don’t want to bother with it... you are OK to go without... My background... I used to work with machinery... not much more complex than our engines... running them was done by instrumentation only... a lot like IFR flight... Ideally, each of the four lines should overlay each other... Sometimes, they are spread out, sometimes they really misbehave and cross... In this case we are looking to see if a small air leak in the intake causes one line to rise to the top... Its a tiny air leak... and may be visible during taxi... During flight the tiny air leak won’t ever be visible... If the leak is large enough, the engine will stumble at low MP... and run fine in flight... So... whenever there is a discussion about my engine not running right... the typical response is... let’s see the data... in this case the issue is so tiny... let’s see the data... to see if this known problem shows up in the data... It looks as if it may have... Best regards, -a- Fun details to be aware of... kind of like how well rigged you can get your flight controls to be... Quote
Ragsf15e Posted May 27, 2021 Report Posted May 27, 2021 25 minutes ago, MikeOH said: @carusoam Sorry to be dense, but I'm just not seeing the point of analyzing engine monitor data. We KNOW there is a problem with the sealing between the manifold and the head as evidenced by the dramatic blue stains. Of what use is revealing altered EGTs, or even CHTs? What would be done differently to fix the issue if you see something in the data versus not seeing anything? Either way, the leak needs to be fixed. In other words, I can't see how the data is going to point you to a more specific location for the leak than what is already evident. I love engine monitor data as much as the next guy, but in this case I'm not comprehending what it brings to the table??? Enlighten me, please. I don’t think it brings anything at this point. I think he just wanted to know if a small intake leak like that can be seen. I don’t see it. 2 Quote
carusoam Posted May 27, 2021 Report Posted May 27, 2021 Taxi Before... Let’s have a look.. line by line... Looking at EGTs... 1) one line is slightly higher than the others... but not really a stand out... looks like E4. 2) One line is really lower than the others... we would like that to get in line a bit better if we had the chance.... looks like E1. Looking at CHTs we see something really interesting... 3) this cylinder is showing a bit cooler than the others... makes you wonder where it’s mounted, what sensor it is using... or is C1 running cooler than the others for some reason... Kind of a preliminary look... so back to the problem description... It really helps to share the link from Savvy... this often gives a ton of extra detail... like how many degrees these lines are off from each other... Quote
carusoam Posted May 27, 2021 Report Posted May 27, 2021 in flight... This one is a bit more fun... 1) Same warm EGT4(?) not really standing out... no real smoking gun... like the blue stain is... 2) Same chilly CHT1 (red colored line) 3) Funky zig zag lines... in EGTs... the data got noisy for some reason... 4) zig zag doesn’t appear to be related to a more defined saw tooth pattern... saw tooth is what you get with sticky valves, that have stopped rotating... Look how smooth the data is near the number one... and ziggy near number three... Single sets of data are not as meaningful as multiple flights showing the same thing... so this is very preliminary... at best... -a- Quote
carusoam Posted May 27, 2021 Report Posted May 27, 2021 11 hours ago, Ragsf15e said: As doc mentioned, the gasket was dried out. No cracks, so that’s good. We did lap the flange, so it’s square. How come nobody told me how much of a PIA it was going to be to access the back bolt on the riser?! Wtf?! It took unhooking the oil return, loosening all the metal baffles and prying them back and then shoving a socket up there! #1 would have been much easier. Carusam, ill try to post some egt data, but I don’t think you’ll see it. I was concerned the bolt may have been missing... Thanks for sharing the detail regarding the gasket... Quote
carusoam Posted May 27, 2021 Report Posted May 27, 2021 Taxi after... The most fun... data. 1) What was the hottest EGT, is now in second place... and not by very much... 2) The coldest EGT is still the coldest... possibly the last to peak when doing a gami spread test... by a bit... a couple or few tenths of a gallon... after the others... 3) same chilly CHT as the others... Quote
carusoam Posted May 27, 2021 Report Posted May 27, 2021 Bummer... All of that analysis... And no smoking Gun... (great news, but would have been nice if there was more of a hint of the gasket decaying...) See if I missed anything... Is that gasket challenge on cylinder #1? (Check my cylinder count and photo recognition skills) Let me know if anyone has questions regarding my observations... See if Paul has any input regarding my amateur Monitor data reading, I think his work is safe. ... @kortopates Thanks for letting me play along... PP thoughts only, not a mechanic... Best regards, -a- Quote
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