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Low Compression, Worn Exhaust Valve Guide, Decisions, Decisions

top it and put in the 160 pistons. I’d be sick to my stomach flying around with a A2B wide deck engine that was still 150 hp.

Exactly what I have been telling myself for quite some time. I have installed all these airframe mods and am leaving 10 hp on the table. Doesn't make much sense.
 
Wow....just think if you had 4 good cylinders @ OSH!

Engine "overhauling" pricing keeps getting crazy. A friend just looked into an 0-300. Through studs were $1000 each. If you go through the cylinders and run it for 500 hours or so and spend $2K of parts/time your extended run will be $4 per hour. So...that is how I would look at it. Keep it safe. Keep your heart out of it. Don't get whileweareinhereitis.

Here is a question: Bad cam with 900 SMOH. Do a bottom end overhaul or just replace cam and lifters?

Tim

That is how I am leaning Tim.

I have replaced cams without overhauling the bottom end. Have a friend here in that situation after 500 hours and have an O-340 at LyCon having the same done at 385 hours. I look at a bottom end overhaul as sending the crank, rods and gears out along with cracnk case. That gets expensive when a visual will tell if cam material scoured the bearing surfaces. New bearings and torque it back together.
 
Steve
You know all 4 exhaust guides will be badly worn with that many hours. You can wait until one of the others miss-seats the valve or snaps a valve and puts you in a tree or the river. So just suck it up and do all 4 guides, and take a hard look at the bottom while everything is off and you are sticking in the pistons. I have a few jars of SUCKITUP on the shelf, I can send you one.;-) Here is a you U-tube video thing of a loose valve miss-seating for those that have not had it happen to them over bad country. https://www.youtube.com/watch?v=x6OyfoV1Z2I
Behindpropellers
I just put new cam and lifters in mine with 1200 hours on motor. I had done all 4 exhaust valve guides at 500 hours so used the same top. Not sure what the right answer is but that is what I did.
DENNY

That is a good video and is what I did to #4 on Saturday. Luckily I caught it early and my valve looks fine so can probably be reused after guides are replaced.
 
Just sent a first run lycoming to overhaul this winter. Had 2100 hrs on it. The engine shop said they get them in for Oh with 3000+ hrs on it. Only problems they see is the bearings wear and then the cases fret and they end up replacing the crank cases at overhaul.
Throw your spare engine on and overhaul yours. Then you will have a nice new engine to put on your exp cub when you get around to building it


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They can't get the crank cases overhauled? My spare engine is a narrow deck 150 hp that is allocated to Cathy's Tri-Pacer and that engine gets gone through and put on my Clipper when it is ready to fly. ;)
 
top it and put in the 160 pistons. I’d be sick to my stomach flying around with a A2B wide deck engine that was still 150 hp.

I have a A2B that’s 150 hp, it has straight steel cylinders that are .020” over with around 600 hrs. Can the 160 pistons be run with these cylinders? I thought they needed to be nitrided and choked, someone please educate me. Plane is not exp...
 
call sals or jj and see if they have a used one, bare, ready to go. sal he probably wont sell a bare cylinder but can try. when you send your used ones in to rebuild, if you have my luck 2 or 3 out of the 4 will be cracked, there goes postage and the inspection fee. harrison sometimes has bares ready to go. sometimes one of these guys are pretty good on price. and then run er.

IMHO buying used cylinders isn't a good option--
that used cylinder might have ten zillion hours on it.
Esp if your cylinders are known time since new or factory reman.
 
Pull the jug, leave the Piston on the rod and replace the guide and try lapping the valves. If valve won't lap grind valves and seat, lap valves and re assemble jug. Don't touch rings or remove carbon from Piston. ….. you'll open up a can of worms if you do more.

I know a lot of people badmouth Mike Busch for some of his comments about mechanics,
but he does come up with some good stuff-- thought provoking if nothing else.
Here's a link to an article about Continental SB03-3 re compression test results.
[FONT=Verdana,Arial,Tahoma,Calibri,Geneva,sans-serif]https://www.airframesalaska.com/v/vspfiles/pdf/TechTalk%20-Powerplant%20Compression.pdf
Don't know if Lycoming has similar guidance for their engines but this article is worth reading in any event.[/FONT]
 
So I have concidered lots of options. I thought of pulling #4 and replacing the guide. I figure if I do one I should do all four. If I am going to have all four cylinders off I want to put those 160 hp pistons in, new rings, hone. Why not go ahead and install new exhaust valves, might as well overhaul them. Not much difference in price between new and overhauled. I have installed several LyCon engines with port and polished cylinders and know how smooth they run and appear to make more power as well. Can you see the snow ball getting larger? It could go on with a complete engine overhaul with balance and reindexing of the crank and why not DLC coat parts and crio them as well and o'ring the crankcase. Not in the budget, my banker retired and I don't want to meet the new, young loan agents nor pay them interest so I am not going there. Hopefully in 1000 hours I don't have a kid in college and another in high school eating me out of house and home and I know the house and hanger will be paid for. I think a set of new Lycoming cylinders from LyCon with their port and polish is the route I am going to take. I could keep flying it cheaper but I don't get paid to work on my own airplane and when I am not working on other's airplanes I would rather be flying mine. Besides, I want what I want so what the hell.
 
My first answer (post #3) was a minimal approach to fly a couple hundred more hours . But......if I were removing all 4 cylinders I would also install new rod bearing at the same time because it's not that much more work or money?

Glenn
 
Do the cylinders come with pistons?


So I have concidered lots of options. I thought of pulling #4 and replacing the guide. I figure if I do one I should do all four. If I am going to have all four cylinders off I want to put those 160 hp pistons in, new rings, hone. Why not go ahead and install new exhaust valves, might as well overhaul them. Not much difference in price between new and overhauled. I have installed several LyCon engines with port and polished cylinders and know how smooth they run and appear to make more power as well. Can you see the snow ball getting larger? It could go on with a complete engine overhaul with balance and reindexing of the crank and why not DLC coat parts and crio them as well and o'ring the crankcase. Not in the budget, my banker retired and I don't want to meet the new, young loan agents nor pay them interest so I am not going there. Hopefully in 1000 hours I don't have a kid in college and another in high school eating me out of house and home and I know the house and hanger will be paid for. I think a set of new Lycoming cylinders from LyCon with their port and polish is the route I am going to take. I could keep flying it cheaper but I don't get paid to work on my own airplane and when I am not working on other's airplanes I would rather be flying mine. Besides, I want what I want so what the hell.
 
IMHO buying used cylinders isn't a good option--
that used cylinder might have ten zillion hours on it.
Esp if your cylinders are known time since new or factory reman.
im running 3 used cylinders, i trust my cylinder shop guy, so far so good, they could probably have 10 zillion hrs, dosent matter if its good, seen guys pull the throttle back on new cylinders to idle when its zero degrees out when landing after running the heck out of it, so how are those, so time wise dosent matter much to me. just sayin a used cylinder is a used cylinder and if everything is in spec and not cracked, im ok with that. if you know your cylinders, and are good with putting guides or seats in and trust your work over a good cylinder shop, its the way to go. i dont mess with guides or seats or have all the tools.
 
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So I have concidered lots of options. I thought of pulling #4 and replacing the guide. I figure if I do one I should do all four. If I am going to have all four cylinders off I want to put those 160 hp pistons in, new rings, hone. Why not go ahead and install new exhaust valves, might as well overhaul them. Not much difference in price between new and overhauled. I have installed several LyCon engines with port and polished cylinders and know how smooth they run and appear to make more power as well. Can you see the snow ball getting larger? It could go on with a complete engine overhaul with balance and reindexing of the crank and why not DLC coat parts and crio them as well and o'ring the crankcase. Not in the budget, my banker retired and I don't want to meet the new, young loan agents nor pay them interest so I am not going there. Hopefully in 1000 hours I don't have a kid in college and another in high school eating me out of house and home and I know the house and hanger will be paid for. I think a set of new Lycoming cylinders from LyCon with their port and polish is the route I am going to take. I could keep flying it cheaper but I don't get paid to work on my own airplane and when I am not working on other's airplanes I would rather be flying mine. Besides, I want what I want so what the hell.

I agree. Besides, your dyin to slap those new pistons in.


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So my new LyCon flow matched cylinders arrived and Friday night and Saturday I spent removing the old and installing the new. A stuck piston pin cap took some extra time so I did not get finished with the install, lack installing induction hoses, drain back lines and baffles. Forgot to order new rocker shafts, button, intake hoses and drain back lines. Lycoming cylinders do come with new piston pins and caps.
20190907_162358.jpg
The 100 degree heat got to me last night and I gave up and called Ken at LyCon with some questions. After emailing him these pictures we have decided the cylinders have been running hot which cause the heat in the valves which cooks the oil off the valves, wears the guides and causes exhaust gasses to escape up the guides creating more problems. The black b rocker arms and springs in the photo album link are evidence. So now I am deciding on a way to read my cylinder head and exhast gas temps. I have been known to leave my mixture out when hitting different gravel bars which I vow to pay more attention to but want to make sure I have proper carburetion and airflow through the engine. One thing leads to another so now I have been looking at engine monitors. I have installed a lot of Electronics International's CGR30P and that would be my preference but is not in my budget. I am looking at the SR-8A which is the most cost effective gauge I have found but if EI has another rebate the UBG16 will be about the same price for a better display of information. I always say these things are snow balls so thought I would follow up with one of my own. ;)

https://photos.app.goo.gl/hvomWHaua3NQjUHB7
 

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You couldn’t pay me anything to take the cgr out of my cub. Don’t they give you a nice discount??


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I would love to give you some Tylenol for the MOREBETTERFEVER. But this is one case that I will add a blanket on top. AT minimum a 4 cylinder Egt/Cht should go on every motor especially with new top ends. It will pay for itself in reduced engine damage and maintenance cost because you can pick out a bad cylinder in just 15 sec. Now if you really want to save money /fly safer add a fuel flow!! This will allow you to quickly manage leaning and knowing exact fuel remaining. A low level pilot does not need to have his head down looking gauges all the time. Once you know the proper fuel flow for given conditions it is a quick set and occasional scan.

Some Pilots/A&P"s/IA"s say they don't like all the engine cht/egt info and it is throwing money down the drain. My feeling is they simply don't know what they don't know and do not want to learn it. Having seen all your work on trying to fix oil/cht temps I know you understand the importance of good information.

The real easy quick money fix is just get the big one and raise you hourly rate! If I ever stop in for a visit I will be happy to pay it!!
Check you're PM.
DENNY
 
I would love to give you some Tylenol for the MOREBETTERFEVER. But this is one case that I will add a blanket on top. AT minimum a 4 cylinder Egt/Cht should go on every motor especially with new top ends. It will pay for itself in reduced engine damage and maintenance cost because you can pick out a bad cylinder in just 15 sec. Now if you really want to save money /fly safer add a fuel flow!! This will allow you to quickly manage leaning and knowing exact fuel remaining. A low level pilot does not need to have his head down looking gauges all the time. Once you know the proper fuel flow for given conditions it is a quick set and occasional scan.

Some Pilots/A&P"s/IA"s say they don't like all the engine cht/egt info and it is throwing money down the drain. My feeling is they simply don't know what they don't know and do not want to learn it. Having seen all your work on trying to fix oil/cht temps I know you understand the importance of good information.

The real easy quick money fix is just get the big one and raise you hourly rate! If I ever stop in for a visit I will be happy to pay it!!
Check you're PM.
DENNY

When I put the cgr in my cub it flew almost 10mph slower. Turns out the old tach was reading a little over 100rpm low. Then I ended up messing with all the baffling, it was leaking everywhere causing high Cht’s. And after that I ended up putting the Sutton exhaust on, it was the only thing to get the oil temps down. Pain in the neck, but how much life did all that add to the engine? Probably a bunch. Now all the cht’s are within 10-20 deg, oil temp is nice and cool and I know how much fuel is in it within 1/10 of a gallon. It’s amazing how a little bit of throttle or mixture causes a big decrease in fuel flow at cruise. Something you wouldn’t know flying fat dumb and happy before.


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Steve, you don't want to hear this but you're really going to want to have "at a glance" info on those expensive new cylinders. Especially with the bar-hopping and other "look outside" activities you like to do. I have a switchable single CHT/EGT display, so I can get all the data on my cylinders but it's a pain and takes a very real amount of time focused inside to look at them all.

If you're on a budget, I'd go with the UBG-16. I'll be doing something similar real soon.
 
...If you're on a budget, I'd go with the UBG-16. I'll be doing something similar real soon.
You can also get just the fuel flow module to go with the UBG-16 which reads out fuel flow only. It doesn't have the fuel used function, but with just the flow it makes it very easy to quickly lean close to what you are looking for. This is what I have in my Cub. I do miss the totalizator functions as they are very useful on trips, perhaps someday I'll upgrade?
 
Burned to white cylinder paint near exhaust is a start to look. Then followed by confirmation of cooked oil in the heads like residue on the valves and inside valve cover. I flew one of those EI CHT-EGT all cylinder display finger gauges during 1986 winter fur trapping in my partner's PA-18 and it informed.

Gary
 
I have the FP5L fuel flow already. Saw the befit in it in my Pacer and in a Super Cub that I fly at minimum fuel on short hops a lot it is great to have. I am going to check with EI and see when they might be doing another rebate on the UBG16. The CGR30P is a great instrument but I gotta work a lot more because I have spent way to many aviation units as of late.
 
I have the FP5L fuel flow already. Saw the befit in it in my Pacer and in a Super Cub that I fly at minimum fuel on short hops a lot it is great to have. I am going to check with EI and see when they might be doing another rebate on the UBG16. The CGR30P is a great instrument but I gotta work a lot more because I have spent way to many aviation units as of late.

You should ask if they'll give an additional rebate for an experimental install :D
 
….If you're on a budget, I'd go with the UBG-16. I'll be doing something similar real soon.

Which instrument are you gonna go with, Cameron--
that MGL Blaze unit that was discussed lately?
I like the looks of that one myself.
 
Which instrument are you gonna go with, Cameron--
that MGL Blaze unit that was discussed lately?
I like the looks of that one myself.

I was, except that I realized just the other day that it is a 4-channel deal. Means I can pick between seeing all 4 EGTs or all 4 CHTs, or just two of each. No bueno. And I feel pretty dumb not realizing that before I bought it.

I peeled the sticker, but I might be able to return it. Otherwise I'll try to sell it and find something that's got all 8 channels I need.
 
If I was experimental I would look at the EDM350 from JPI. I am not a JPI fan due to my experience with customer service but that is a quite capable instrument for the money. Installed one in a Carbon Cub SS.

I called Electronics International but they are not planning on another rebate until Sun &Fun. Sales is checking with management to see if they would give me the rebate that just ended the end of August but no return phone so far.
 
Steve, i went with a Lycon engine last build, Lots of power but lots of heat issues to sort out, only way to track cooling progress was with a reliable 4 cyl monitor
I've had great luck with Jpi edm 700 w/fuel flow on last three planes and would not fly without one.
Had a display crap out once, but they took care of it promptly.
 
EI hasn't called back but a friend who races on the salt flats offered me his SR-8A he had set up to read 8 EGTs. Will just have to buy 4 CHT probes. Will go that route for now, the bank account is tapped out between these cylinder, an old Toyota truck I bought for Lee since he just got his drivers license and two trees for my front yard where our big tree didn't come back last spring. Oh to think back to the days when I lived in the hanger and spent all my money on airplanes. ;)
 
Once you have installed a multi probe monitor and your top is broke in, what’s your game plan on mixture settings? 125* rich of peak? Maybe 100*? If hoping sandbars, loping along at 2100rpm, 3-4k DA does it matter if you’re running near peak? What about longer x countries up higher? I’m wondering if I’ve been running too lean.
 
Once you have installed a multi probe monitor and your top is broke in, what’s your game plan on mixture settings? 125* rich of peak? Maybe 100*? If hoping sandbars, loping along at 2100rpm, 3-4k DA does it matter if you’re running near peak? What about longer x countries up higher? I’m wondering if I’ve been running too lean.
Lycoming says that when running at 75% power or less that it is permissible to run at peak EGT. An inexpensive manifold pressure gauge or perhaps a manifold module for the SR-8A would be helpful in determining the power setting.
 
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