In-Flight Loss of No. 3 Cylinder; Need overhaul recs

frcabot

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frcabot
Long story short.

Suffered a sudden (initially-partial) loss of engine power near KBFL, made an emergency landing safely at the airport on Saturday.

Audio is on liveleak for those who are so inclined. Starts about 15:45 in (the initial radio calls were on 121.5 and I had a guard nazi yell “you're on guarddddd" to me, I replied “I knowwww," lulz). http://archive-server.liveatc.net/kbfl/KBFL-Nov-07-2015-2330Z.mp3

Got a call from the local mechanic today, who informs me that it looks like my number 3 cylinder "ate a valve" and is "pretty beat up inside."

Engine is 2100 SMOH but got mid-life bottom and top overhauls after the previous owner did a gear-up landing. At the annual inspection in August, all compressions were good (the No. 3 cylinder had I think 73 or 74) and no problems were detected.

So I'm not sure how I got from a healthy engine to a disintegrating cylinder in a couple months and only 20 or so hours of flight time, but here we are.

I'm wondering whether it makes more sense to just do an overhaul from a reputable shop (given the TSOH) or an individual cylinder replacement.

Thoughts? What are my options for good, reasonably priced overhaul shops? Obviously the plane is not going anywhere soon.

It's an M20J and so the engine is a Lycoming IO-360-A1B6.
 
Long story short.

Suffered a sudden (initially-partial) loss of engine power near KBFL, made an emergency landing safely at the airport on Saturday.

Audio is on liveleak for those who are so inclined. Starts about 15:45 in (the initial radio calls were on 121.5 and I had a guard nazi yell “you're on guarddddd" to me, I replied “I knowwww," lulz). http://archive-server.liveatc.net/kbfl/KBFL-Nov-07-2015-2330Z.mp3

Got a call from the local mechanic today, who informs me that it looks like my number 3 cylinder "ate a valve" and is "pretty beat up inside."

Engine is 2100 SMOH but got mid-life bottom and top overhauls after the previous owner did a gear-up landing. At the annual inspection in August, all compressions were good (the No. 3 cylinder had I think 73 or 74) and no problems were detected.

So I'm not sure how I got from a healthy engine to a disintegrating cylinder in a couple months and only 20 or so hours of flight time, but here we are.

I'm wondering whether it makes more sense to just do an overhaul from a reputable shop (given the TSOH) or an individual cylinder replacement.

Thoughts? What are my options for good, reasonably priced overhaul shops? Obviously the plane is not going anywhere soon.

It's an M20J and so the engine is a Lycoming IO-360-A1B6.

I'm not a mechanic (at least not for airplanes) but I think this is really hard to answer without knowing what was done at the mid-time bottom & top overhauls. New crank, pistons and cylinders? Replace #3 and probably keep going. Checked for in limits but 2nd or 3rd run crank? Time for an overhaul.

My $.02.

John
 
obviously I wasn't there but it seems like on the initial call you were only 2 miles away from the field yet it took over 10 minutes to land and at some point in the middle of all that you were at 4500'. seems to me like in a mooney, even minus one cylinder, and after declaring an emergency, you could have been on the ground in 2 minutes. but of course I'm monday morning qb'ing, so well done getting that puppy on the ground!
 
obviously I wasn't there but it seems like on the initial call you were only 2 miles away from the field yet it took over 10 minutes to land and at some point in the middle of all that you were at 4500'. seems to me like in a mooney, even minus one cylinder, and after declaring an emergency, you could have been on the ground in 2 minutes. but of course I'm monday morning qb'ing, so well done getting that puppy on the ground!

Yes, that is a bit of monday morning quarterbacking since at the initial call I was 25 miles away. Once I switched frequencies and was speaking to Bakersfield approach, the controller clearly says: "Radar Contact, two-zero-miles south of the airport." Where did you get 2 miles from that?
 
Victor Aviation, Palo Alto, seems to do a good job on cylinders. Might be over-kill for a one-off though. They didn't have a core charge on my TSIO-360 cylinders because they have so many laying around. Dunno 'bout the Lyc. 360. Can't hurt much to give them a call, they do seem to know what they are talking about.
 
Yes, that is a bit of monday morning quarterbacking since at the initial call I was 25 miles away. Once I switched frequencies and was speaking to Bakersfield approach, the controller clearly says: "Radar Contact, two-zero-miles south of the airport." Where did you get 2 miles from that?

oh yeah, 20. ok, scratch that. jeez, 'scuse the fk outta me.
 
Also it takes a while to get down from 11k feet anyways. At 1k ft/min it's still 10 mins even if I'm circling over the airport. Not like the engine was on fire so I had no reason for an emergency decent, even if I had been only 2 miles away. Better to put off our deaths for a few more minutes. Lol

On final approach, after my engine failed I was still at 4500 ft and had to do some s turns to lose altitude so I wouldn't overshoot the runway.
 
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I'd overhaul it.

Or buy a new engine, that way you can be assured that every part in the engine is new and has a factory warrantee.
 
The engine case got opened midway through? Hell, you got a new engine baby. It's a Lyco 360, you're good. Just put a new #3 cylinder and get back to flying. Cylinders are accessories. They fail. The only part that sucks it's that they are the angled valve variety (my arrow has the same kind of engine) so the cylinder doubles in price compared to parallel valve. That's how they get the 360 to 200HP though, oh well. Much cheaper than an overhaul.

My best friend's name is I.R.A.N and his goal is to make sure my fuel bill exceeds my maintenance bill.
 
If there are no other signs of it needing an overhaul, I would just replace the cylinder.
 
Is the airplane at your home base? If not I'd be tempted to find a cylinder, install it, and get the airplane home or to your preferred mechanic so you can decide what to do at your own pace.

Ultimately, I'd likely be considering an overhaul though.
 
The engine case got opened midway through? Hell, you got a new engine baby. It's a Lyco 360, you're good. Just put a new #3 cylinder and get back to flying. Cylinders are accessories. They fail. The only part that sucks it's that they are the angled valve variety (my arrow has the same kind of engine) so the cylinder doubles in price compared to parallel valve. That's how they get the 360 to 200HP though, oh well. Much cheaper than an overhaul.

My best friend's name is I.R.A.N and his goal is to make sure my fuel bill exceeds my maintenance bill.

It's just a matter of, pay me now or pay me later. the only thing cheap in aviation is the owners.
 
I have a different question. Would an engine monitor have given the OP fair warning that something was up (defined as not having the problem happen in the air)?
 
I have a different question. Would an engine monitor have given the OP fair warning that something was up (defined as not having the problem happen in the air)?

Nope. Valves break suddenly.


Valve heads break off sometimes due to corrosion pitting of the stem. And that leads us to wonder if this was the case here, and if the rest of the valves in that engine are similarly pitted and about ready to pop off, too. Replacing a cylinder might be throwing good money after bad.
 
Did the piston get holed? If so, you got metal running through most parts of the engine. If the piston isn't completely trashed, and the oil check comes back ok, without a lot of metal in it, I'd be temped to put a jug asm on it and see what you get. For sure look closely at the oil you get out of the engine though.
 
I had just landed, parked the club plane at Atlantic when I heard your call come in,
I saw you coming in and you made an awesome landing,

Bummer about the engine,
 
Did the piston get holed? If so, you got metal running through most parts of the engine. If the piston isn't completely trashed, and the oil check comes back ok, without a lot of metal in it, I'd be temped to put a jug asm on it and see what you get. For sure look closely at the oil you get out of the engine though.


+1......
 
I had just landed, parked the club plane at Atlantic when I heard your call come in,
I saw you coming in and you made an awesome landing,

Bummer about the engine,
Thanks, appreciate it. It was a little nerve-wracking knowing I was only going to have one shot at the landing but fortunately that went OK.

I'll speak to the mechanic and see what he says about replacing just the cylinder. I don't know nearly as much as some of you regarding what to look for and how to direct the mechanic what to inspect, but we'll see. It doesn't make sense to throw good money after bad, but if the rest of the engine is fine and the other parts are well under TBO, there may not be any sense in doing a major overhaul prematurely.

Sent from my SAMSUNG-SM-G870A using Tapatalk
 
Thanks, appreciate it. It was a little nerve-wracking knowing I was only going to have one shot at the landing but fortunately that went OK.

I'll speak to the mechanic and see what he says about replacing just the cylinder. I don't know nearly as much as some of you regarding what to look for and how to direct the mechanic what to inspect, but we'll see. It doesn't make sense to throw good money after bad, but if the rest of the engine is fine and the other parts are well under TBO, there may not be any sense in doing a major overhaul prematurely.

Sent from my SAMSUNG-SM-G870A using Tapatalk

Will you ever trust that engine again?
what is the only reason to overhaul any engine in part 91?
 
Long story short.

Suffered a sudden (initially-partial) loss of engine power near KBFL, made an emergency landing safely at the airport on Saturday.

Audio is on liveleak for those who are so inclined. Starts about 15:45 in (the initial radio calls were on 121.5 and I had a guard nazi yell “you're on guarddddd" to me, I replied “I knowwww," lulz). http://archive-server.liveatc.net/kbfl/KBFL-Nov-07-2015-2330Z.mp3

Got a call from the local mechanic today, who informs me that it looks like my number 3 cylinder "ate a valve" and is "pretty beat up inside."

Engine is 2100 SMOH but got mid-life bottom and top overhauls after the previous owner did a gear-up landing. At the annual inspection in August, all compressions were good (the No. 3 cylinder had I think 73 or 74) and no problems were detected.

So I'm not sure how I got from a healthy engine to a disintegrating cylinder in a couple months and only 20 or so hours of flight time, but here we are.

I'm wondering whether it makes more sense to just do an overhaul from a reputable shop (given the TSOH) or an individual cylinder replacement.

Thoughts? What are my options for good, reasonably priced overhaul shops? Obviously the plane is not going anywhere soon.

It's an M20J and so the engine is a Lycoming IO-360-A1B6.


If they did a top and bottom at mid time, then it would be a mid time engine, not a run out. They did an IRAN and SB/AD at mid time, and without seeing the work orders, there is no great significance in engine life renewal involved in bringing it back to legal from a prop strike. The real question is what have your oil analysis been showing? Lunching one valve itself is not indicative of needing an OH, but with a 2100hr engine, it may end up be the most logical time to OH.
 
If they did a top and bottom at mid time, then it would be a mid time engine, not a run out. They did an IRAN and SB/AD at mid time, and without seeing the work orders, there is no great significance in engine life renewal involved in bringing it back to legal from a prop strike. The real question is what have your oil analysis been showing? Lunching one valve itself is not indicative of needing an OH, but with a 2100hr engine, it may end up be the most logical time to OH.

If the oil analysis and filter have consistently looked good, and if the cam looks good under the cylinder that's removed, I would just replace the cylinder and keep flying. As Henning says, it is mostly a mid-time engine.

There's no point in doing unnecessary overhauls. They cost a lot of money, and you're more likely to have a failure within 100 hours of a major overhaul than just about any other time.
 
If the oil analysis and filter have consistently looked good, and if the cam looks good under the cylinder that's removed, I would just replace the cylinder and keep flying. As Henning says, it is mostly a mid-time engine.

There's no point in doing unnecessary overhauls. They cost a lot of money, and you're more likely to have a failure within 100 hours of a major overhaul than just about any other time.

I did not say that, I said the opposite, I said that without seeing the work orders of what was done and replaced at the prop strike inspection and tear down, this is a run out engine that has been opened up before is all. If they would have met the requirements of an overhaul, they would have called it one. Satisfying the SB/AD on the prop strike is a far cry from an overhaul.
 
Good job staying calm and doing it right! I may have forgotten the gear hahaha! :D
 
If they would have met the requirements of an overhaul, they would have called it one.

Not really, many engines meet the requirements of a overhaul except for maybe one or two items. so they are signed off as a repair, this engine maybe one of those, or it may have been simply repaired and returned to service with only a few parts replaced.
I've seen engines that were opened for inspections and reassembled with the same bearings that came out.

No one can tell you what is in this engine until it is torn down.
 
Not really, many engines meet the requirements of a overhaul except for maybe one or two items. so they are signed off as a repair, this engine maybe one of those, or it may have been simply repaired and returned to service with only a few parts replaced.
I've seen engines that were opened for inspections and reassembled with the same bearings that came out.

No one can tell you what is in this engine until it is torn down.

What idiot does that when the insurance is footing at least the majority of the bill?:dunno:
 
It was an official top overhaul and official bottom overhaul. Not a repair. Also, they occurred at different times.

Sent from my SAMSUNG-SM-G870A using Tapatalk
 
what is an official top overhaul?

Replacement of all cylinder asms, pistons, rings, wrist pin, pin boss caps, and associated gaskets and seals.

That's as 'official' as I can make it.

<edit: I guess some would include inspection to tolerance in those components, but that stretches the term 'overhaul' pretty thin.>
 
It was an official top overhaul and official bottom overhaul. Not a repair. Also, they occurred at different times.

Sent from my SAMSUNG-SM-G870A using Tapatalk

In that case, you are not gaining anything by paying for a full overhaul now, if there are no other signs of it needing one. Put a new cylinder on it and fly.

My guess is, the previous owner paid a little extra for the insurance tear down to qualify as a bottom overhaul, and had topped it out of necessity either before or after. In my book, that qualifies as a major overhaul. That they were done separately makes no difference. You said the top and bottom overhaul were done about 1000 hours ago, so consider it 1000 SMOH

That both top and bottom were an official overhaul makes a difference, as others have pointed out. An official overhaul has tighter tolerances and resets TBO.
 
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<edit: I guess some would include inspection to tolerance in those components, but that stretches the term 'overhaul' pretty thin.>

If the overhaul manual has a measurement spec for the component, and its within tolerances I don't think it stretches the term thin, as you put it. There is no point in chucking perfectly good parts.
 
If the overhaul manual has a measurement spec for the component, and its within tolerances I don't think it stretches the term thin, as you put it. There is no point in chucking perfectly good parts.

Well alrighty then. If the ring end gap for a particular engine is 0.026, and it measures at 0.024, slap it back on and run it. Officially good to go, and yup - write it up as an 'overhaul'. :lol:
 
Any CHT indications before all h---- broke loose? Or rough running strangeness?
Nope. Fine one sec with all indicators in the green. Then weird noise and egt and cht needles went to minimum peg and I immediately put the mixture back in. When that didn't work I plugged in nearest major airfield and made the turn, turned on boost pump just in case and began declaring an emergency. Basically, no warning whatsoever, no strange noises, nothing. Oil pressure, oil temp and fuel pressure stayed normal throughout.

In retrospect the engine seemed to start easier than it usually does which maybe could have been an indication of low compression?
 
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Well alrighty then. If the ring end gap for a particular engine is 0.026, and it measures at 0.024, slap it back on and run it. Officially good to go, and yup - write it up as an 'overhaul'. :lol:

Some things are supposed to be replaced during an overhaul. Rings might be one of them. But yep, if the manual gives a spec and they are within the spec lycoming or continental considers them good enough to make another 2000 hours.
 
I still have a cylinder and piston on my desk here from when my Gopher35 did the same thing. Not only did it beat the hell out of the cylinder and bent the piston such that the ring lands have a nice dip in them it went all the way through the piston and beat up the c-rod as well. By the time I finished having the engine torn down, we pretty much declared it a total loss.
 
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