Lyc(clone) Reliability

(I hope this is a good idea....but I occasionally have bad ones!)

OK, here's a question for folks that have considerable time flying behind Lycoming (and Lyclone) engines....how many folks have ever experienced an in flight engine stoppage that was directly caused by a failure in the "core engine". I'm not talking about running out of gas, or fuel starvation due to airframe fuel system failures - something that went wrong with the basic engine - Crank failures, case cracks, cam failure, lifters, rod breakage, sucking a valve....the intent of this thread is to see just how reliable/unreliable this power plant really is.

OK, I have my bias - I believe that the core engine is pretty much bomb proof, and I can't remember many stories of actual in-flight engine failures here on the forums in the past couple of years, so I think that belief is born out. But maybe we can learn a little bit (in a non-scientific, non-statistical way) about their reliability - at least anecdotally. And folks makign engine choices will ave a thread they can take a look at for some datapoints.

If you've had such a failure, please tell your story...but add in how many hours of flying time you have behind these engines in total...I expect someone with a lot more hours has just had more probability to experience a problem! It will also be more meaningful if you tell us how many hours were on the engine...

And to start things off....I have nothing to report.....(35 years worth)

Paul

Engine Problems

Two engine problems, both in Hawaii:

Lost one cylinder on a C-152 over the mountains on Oahu...but I don't fault the engine. Mechanic over-torqued the spark plugs during a 100 hr inspection; a chunk of spark plug bounced around the #2 cylinder, put a hole in the piston and screwed up the valves. Ruined my afternoon of flying, but I was able to maintain altitude and make it back to the field and land.

Also lost power in another C-152 a friend was flying (I was safety pilot) after takeoff on Kauai...again, I don't fault the engine. Mechanic failed to replace the plugs after a 100 hr inspection and the plugs were almost completely worn out; runup was good but we lost power on takeoff. Were able to climb and return to the field.

For what it's worth, both mechanics had their tickets suspended....don't know what the final outcomes were, but it made me rethink the rental aircraft fleet for a long time!

Also

Regards,
Mike

I've been in one situation where a Lycoming O-360 in a fixed gear Cardinal had a situation where the exhaust valve on the number 1 cylinder froze in the open position while on climb out right after takeoff . Immediate effects were that the engine ran like ****(obviously), a lot of power was lost (obviously), but the pilot was able to circle around and land without problem. Thankfully, the end result was the overhaul of that cylinder and nothing more. At the time, I believe the engine had around 600-700 hours since new.

I also have a personal friend and fellow CFI who has had two partial engine failures, both while working on his Commercial in a Cessna 172RG (again, an O-360) where in both cases he had cracked cylinders. The engine was "mid-time" during both incidents, approximately 1000 hours since overhaul. Thankfully both times were right over an airport and he landed without problem.

Closest I ever came was a rented 172 that lost a mag. I refused to fly it back to it's home base, and the owner came and picked it up and lost the second mag on his way back. Running rough is better than not running at all, I have heard. Another case of rental maintenance!

Two weeks ago a friend in the next hangar did lose a cylinder in a Colt. Stuck
valve that scrapped out the cyl. He was able to make a nearby field with enough power to hold altitude. Everything else I have been involved with was someone's fault.

Bob Kelly

Swallowed a valve in a rental 172, high time engine. Partial power, still in the pattern, normal landing, non-event. It went in for complete OH as a result, it was a training aircraft that was regularly abused, at an FBO that was known for horrible maintenance practices.

40 years and 5 months total experience behind Lycoming, Continental, Rotax and Jabiru. Nothing to report.

1 failure

While doing steep turns with the hood on (with CFI in right seat), the engine stopped turning.....NEAREST on the Garmin GPS 90 (it was a long time ago) and an uneventful landing on a grass runway that happened to be nearby (common in Texas). C-150 with Cont. engine. Crank had broken...yes, broken.

I didn't have to pay for that half hour .

dr

C172 Piston exit aircraft...

My partner had a piston completely exist our C172 through the oil check door. It was a Continental 0-300. The piston ended up in a field. He was able to fly under partial power to a nearby airport. If I remember right, the engine had low time on it. Something like 200 hrs. I wasn't partners at that time. If I remember right, it was found to be caused by over torqued piston rod connecting bolts.

paul paul paul

what are you smokin? you know real aircraft engines never quit or cause trouble in flight..... at least thats what we tell Ross just kidding Ross.
this should brighten your day. this is one on a twin .the owner/pilot was in the back while his very young son and freind (a pilot as well) were flying at night when it had an iron Hemorrhage this was the left engine and what was left of the engine.

Interesting responses so far....(and a great picture William!). If I count right, only one "the engine stopped making noise completely" case, and then some partial power cases. I intended the rules to be only cases that YOU have experienced YOURSELF, to keep the sample restricted to the 6,000 registered members here....otherwise, we could get every engine failure story ever told (and many of them get better and better with the telling - we all know that!). But it is interesting to see what happens when a rod tries to exit the case!

nothing to report

500 hours mostly rental aircraft nothing to report other than a F33 Bonanza with high hours that stalled after exiting runway (very low idle).

Bill

In discussions on this same topic, my CFI - who had 8500 hrs at the time, nearly all behind Lycos - said he never had an engine cease to run while flying. He had one that sucked a valve, and a couple of others that had top-end problems that forced him to land at a nearest, but never had one quit completely. He attributed it to the "bullet-proof" nature you're alluding to, Paul.

Terry

Cytoxin's Photo

Cytoxin's photo doesn't look like a Lyc(clone)

Mag Failure

This isn't an engine core item, but... Acrosport 1 with 160hp Lyc 0-320. Failed impulse coupled mag. Happened on run-up thankfully, but other mag was still good.

Failure mode involves some explanation. The coils on older model Bendix mags are held in with wedge like keys. They are not held in place with screws or bolts like you would think, but rather just steel wedges. Generally these work well, but c'mon, wedges? I was shocked when I discovered the design. Anyway, one wedge worked its way loose right into the main plastic timing gear and well, you get the idea.

Rob

Continental O-200A

I had a rocker arm boss fail on my C-150. I flew it about 10 miles to the nearest airport and landed. I had to reduce the rpm to about 1700 to keep the engine from shaking violently.
Total flying hours on (2) different C-150's--800 hours
The c-150 that lost the rocker arm boss was in its second major overhaul with about 700 SMOH on it.
Other than that, both O-200's ran flawlesly.
Jim

SMOH..... What does that mean?

(1) Could be the engine was taken apart. Something was measured. Then put back together.

(2) Could be the engine was taken apart. Parts were replaced with used. Then put back together. Some of the parts could have thousands of hours on them.

(3) Could be the engine was taken apart. All new jugs. First run case, rods, crank, (non AD I hope) checked overhauled. Then put back together. Test run.

I saw an engine in a -4 that threw a rod with 10 hours on the engine SMOH. Big hole in the crankcase. Did the rod have 10,000 hours? No one knew.

I would like to know stuff like:

TTSN of all the parts in the engine. I don't want parts with unknown times. Like RODS!

SB 388C results

SI 1425 accomplished

25 hour oil changes

Oil sample results

Oil suction screen results

Oil filter results

By the time the top has run 2,000 hours; Burned 20,000 gal of 100LL; $ 80,000 of gas!!!!! ......... I just want to thank them for their service and blow $ 4K on 4 new jugs.

I like to think the Lyc is bullet proof, but I also want to stack the deck in my favor.

he did say lyc clone but

so many here were posting their time in 150s (which i love the little birds) i figured id show that continetal pic that i took one day before flying. it was what i had to think about while i was flying in the rented 150.....that picture helped me rationalize the new engine price. and why i sent my used 0 320 back to the crop duster it came from. as for as the plane, the folks said it was a non event for them it had happened before. ????makes you wonder about the value of a new/ reconditioned oil cooler and lines doesnt it?

added i would bet that the pictured engine was simply left to oil starvation by lazy complacent pilot. this would have been caught by and oil lab IMHO if it had not been a sudden catostrophic failure.probally caused simply by too low of an oil level.

Mine too

This may be a little off topic but there is a warning message to this story.

Back in the early 80's I was using two Cessna Agtrucks in my sparaying business and they had IO-520/300 horse Conti's and often shook the case-mounted oil coolers so badly that they cracked so we always had a spare around. My pilot changed one late one evening and used silicon as a gasket since the old one had torn. The next morning on the second load, the engine threw a rod cap through the case, just like in Cy's picture, while on a swath run at three feet above the cotton. Being a very quick thinker, he dumped the load in seconds, made a 180 degree lazy eight type turn and landed in the field he'd been spraying.

Later examination revealed a small piece of silicon in the oil hole in the crank at that rod location. It got there when it oozed between the oil cooler flange and the case, entering the oil galley. Never use silicon for cases like this....

Regards,

so many here were posting their time in 150s (which i love the little birds)..... i figured.....

Click to expand...

This may be a little off topic but there is a warning message to this story.

Click to expand...

Ah, the venerable 150. While giving an introductory flight over flood waters in Missouri in 1993, the engine suddenly swallowed a valve and the airframe shook so violently, the instrument panel appeared blurred. The RPM's dropped dramatically.....so much so that it was impossible to maintain altitude but was close enough to the airport I elected to alert local traffic and press on, especially since my alternate options were limited to picking a flooded field or a very busy Interstate 70 to alight upon. The slow descent continued and similiar to the sequence in the movie "Always" the main landing gear finally made contact with the ground on the margin of grass and pavement on the now active runway. We were greeted by at least 20 people who rushed the airplane looking for a cheap thrill and I was very glad to disappoint them.

My other notable incident occurred just a few years ago, had no witnesses present but at the time seemed every bit as dramatic. I wrote about it for our Chapter newsletter. Bottom line: Mufflers can bite too!
http://www.eaa32.org/Articles/muffler_mishap.pdf

Ironflight said:

Interesting responses so far....(and a great picture William!). If I count right, only one "the engine stopped making noise completely" case, and then some partial power cases. I intended the rules to be only cases that YOU have experienced YOURSELF, to keep the sample restricted to the 6,000 registered members here....otherwise, we could get every engine failure story ever told (and many of them get better and better with the telling - we all know that!). But it is interesting to see what happens when a rod tries to exit the case!

Click to expand...

Hehe...this is going to be one looong thread. I wonder if a poll would be better.

I've lost ignition systems a total of 3 times in 1,000 or so hours.

- I had a mag go out in a Tomahawk.

- The Electroair ignition in the RV suffered infant mortality at about 40 hours.

- And today (at the very end of a 3 day, 1500 mile X/C), the Electroair ignition went out again. I have not (yet) diagnosed the problem, and the troubleshooting may be difficult because the ignition came back to life after landing. At this point, there is no telling if the problem is in the ignition itself or some other issue like a worn switch or poor wiring connection.

I've also experienced a stuck carb float.

I'm in agreement with those who believe that the systems in the aircraft are far more likely to fail than the engine core itself.

Thread drift

Paul
It was a nice try on your thread.
Oh well!

jthocker said:

Paul
It was a nice try on your thread.
Oh well!

Click to expand...

Yup...This one skitterd into the busshes prettty quick....I guess I didn't communicate the intent very well...

But I have yet to see many core engine failures in all the interesting stories!

Paul

I've been instructing in a particular C-172 for awhile now... Lycoming 160hp... I have around 1,100 hours in that (and one other) C172... and neither have ever even made a funny noise.

Both are operated by good FBOs with good maintenance, I might add.

I'm a believer....

Engines can fail, but it's worth the risk.

Folks,
I can see a problem with this poll.

Some people, including me, don't want
to give out a lot of details about their
engine failures. In my case, it's partly
because I don't really know enough details
about my Lycoming engine or why it failed.

I'll say this much:
I did have a massive failure, under warranty,
at 78 hours, TTSN, this year. The #3 cylinder left
the case after a bolt failed on the crank end of
the connecting rod. The engine ran long enough
for me to make a safe landing in a clover field
from about 4000 feet AGL. I had to remove the
wings to return to my hangar and spent all summer
putting my RV back together and installing another
engine. It's on a RV-7A with an O-360, carb and two
mags. I'm back in the air with about 12 hours on a
new engine. Both engines were built up from a mix
of new Lycoming and aftermarket vendor parts.
I don't feel the engine builder was at fault and won't
mention their name. This was my third, but most abrupt,
engine failure in just over 50 years of flying about
1300 hours in light aircraft.

I'm writing this to make you aware that engines
can and do fail and please keep some options open and
practice your engine out procedures, at least do a
'what if it stops' in your head.

Thanks for thinking about it,
Tom

I don't think anyone believes that an engine can't fail... that'd be an unfortunate assumption, wouldn't it?

I have had good luck, but maybe it's just that... luck. But I also think it comes down to maintenance/care as well. That at least enters into it.

Not a Lycoming, but a Continental a few hangers down from me had the cylinder crack all the way around the combustion chamber. The head pushed away from the rest of the cylinder, both valves closed, and the engine ran on minus one cylinder. Very impressive to have a failure mode that just loses one cylinder.

(WARNING, THREAD DRIFT FOLLOWS) A small leak in the intake gasket of my chevy a few years ago took the whole engine down.

Simple don't fly

If you want make a Lyc engine failure a very unlikely event:

>Maintenance maintence maintence maintence
>Inspection inspection inspection inspection
>Operate within limits, operate within limits
>Fly engine frequently, Fly run engine frequently

Many failures come from corrosion, poor maintence, poor inspections and abuse but not all.

Some failures do happen from unseen flaws in the original parts or sometimes improper assembly. Those have made the news & SB's, AD's and lawsuits. Continental and Lyc suffered a rash of crank shaft process and production issues in the last 15 years. Sadly the problem was with an existing part and design that was fine for +30 years. The problems only happened due to seemingly small changes in manufacture process or farming it out to a sub-vendors. That's why in aviation, the FAA is so strict about standards and NO deviation from that standard. If it works and ain't broken don't fix it.

To put it in prospective. If you want make an engine failure an impossible event, don't fly.

Fortunately catastrophic failures are rare.

If you want to understand engine failures and everything that can go wrong, buy the book from Sacramento Sky Ranch - "Lycoming & Continental Engineering Manual". You don't have to be an engineer to understand it. A fascinating book with lots of examples of failures with pictures, with the failure analysis. It's only $20 and is the best $20 you can spend on the topic.

Know Thy Systems!

CAUTION: serious lack of engine system knowledge contained below! This happened when I had just under 200 hours total PIC time and about 110 hours in the airplane.

2 years ago I was flying my Cherokee 235 (O-540) with about 1400 hours SMOH on a day-VFR flight for some touch and go's. Turning East out of my home airport of Addison, TX, I noticed my AI was not responding. Not wanting to troubleshoot at 100 ft AGL, I continued my climb and easterly heading. I looked over and saw that my vacuum pressure was 0. My thought was that my vacuum pump had failed, and since it was day-VFR, I decided to continue the flight and get it looked at when I got back. About 5 minutes later, the engine quit making noise.

I didn?t have much altitude to play with, so I went through my engine failure checklist in my head, but none of it did anything. Lucky for me, I had just flown over the McKinney airport. I made a 220 degree left turn to line up for final to 17? Right into a 20 knot headwind. I was already at best glide, but the 235 comes out of the sky like a brick with no power, and I quickly made the decision to plan for ?alternate arrangements?. I cleared the airport fence and landed in a field to the left of the approach lights. No damage to me or the airplane. I remained calm during the encounter, but once on the ground had an adrenaline rush that I?ll never forget. Neither will the fireman that I hugged in a moment of celebration as he pulled up just as I was exiting the airplane.

For 3 days after this event, I was clueless as to how a vacuum pump failure could cause the engine to stop. Then I learned about a part of the engine called the accessory case. One gear goes, they ALL go! Upon further inspection by the good folks at Zephyr Aircraft Engines, one gear (can?t remember which one) got a little loose, and that was it. My vacuum pump didn?t fail, it just stopped getting RPMs from the accessory gear.

Total flight time from takeoff to touchdown was 13 minutes. For those of you who don?t know the Addison Airport, if my engine would have quit 5 minutes earlier, I probably would have been left with bad and worse for landing options due to heavy residential development.

Final damage was a ?bottom overhaul? since the engine had sucked up a lot of metal while windmilling plus the accessory case rebuild.

Lesson #1: Things aren?t always as they appear.
Lesson #2: Know your systems!
Lesson #3: I have my skydiving background to thank for this one? If your engine quits, constantly be evaluating your landing options. Don?t get fixated on your primary target, and don?t take a path to your primary with no options in between. I probably would have made the runway had I made a bee line for it, but that would have taken me over nothing but trees. I altered my final approach so I could over-fly a few fields between me and the runway that would have been good options had I needed them.
Lesson #4: It didn?t have a huge impact on my situation, but I delayed my ?may day? call because I thought I had partial engine power for the first minute or so. As soon as my engine stopped making power, I looked down at my tach and saw 1500 RPMs. Through all my power off practice, I never thought about what I?d see in the cockpit if the engine quit. So until I started slowing the plane down to best glide, I thought I had partial engine power because of the tach reading. CFI?s? Make sure you talk to your students about what instrument indications they might see in the case of an engine failure!
Lesson #5: The best way to learn about your airplane is to build it yourself!

0-470

This did not happen to me personally, but I have witnessed an L-19 equipped with a Cont 0-470 crack a jug in flight. Pilot had a glider in tow and was overhead the airfield; glider released and L-19 landed without incident. Wish I had a pic of the crack, it almost took the whole top right off the cyl.

DBone said:

For those of you who don?t know the Addison Airport, if my engine would have quit 5 minutes earlier, I probably would have been left with bad and worse for landing options due to heavy residential development.

Click to expand...

This is exactly why we no longer allow "amateur-built" first flights out of Addison any more.