How often do engines make it past TBO?

bnt83 said:
Currently looking at an O-360-A1F6D that was last overhauled in 1989...
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Brian, my O-360-A1F6D was last [field] overhauled in 1978 and now has 1200 hours on it. Last week at annual, all 4 cylinders were 79/80. There has never been any metal in the filter, and the engine pulls the plane at book speeds and fuel burns, so it's making book power.

Since I bought the plane in 2009 I've done a wobble test on the valves (they were and are fine), overhauled the Marvel carb, IRAN'd the D-3000 magneto, changed the rubber intake pieces, and have changed oil and filter every 25 hours (twice a year - spring and fall). I've also put a new alternator and vacuum pump on it. I have been putting 50-60 hours per year on it but as you can see, it's only had an average of 33 hours a year since overhaul.

I've been everywhere I can be with a borescope and have seen no problems. There are no external cracks.

The airplane has always been kept in an enclosed, environmentally controlled hangar and I think this isn't discussed as much as it should be but is probably one of the biggest contributors to engine longevity.

I can't speak to 2000 hour TBOs but I personally believe that 12 years is a number designed to increase business for overhaul shops. I trust my engine a lot more than I would a recently overhauled one and am in no hurry to get it overhauled.
 
Tom-D said:
That's just you. If you didn't trust it, why did you fly it?
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time Tom.....It takes time to prove out infant mortality failures.

Anything beyond the first 100-200 hrs should be good to go....but, if something isn't assembled or manufactured correctly you'll know within this period.:wink2:

From a reliability standpoint....I want all my parts to be old, real old, cause most if not all core steel parts have infinite life on the S-N diagram. Now, aluminum cylinder heads.....not so much, I'd like new ones every time.
 
JohnAJohnson said:
Brian, my O-360-A1F6D was last [field] overhauled in 1978 and now has 1200 hours on it. Last week at annual, all 4 cylinders were 79/80. There has never been any metal in the filter, and the engine pulls the plane at book speeds and fuel burns, so it's making book power.

Since I bought the plane in 2009 I've done a wobble test on the valves (they were and are fine), overhauled the Marvel carb, IRAN'd the D-3000 magneto, changed the rubber intake pieces, and have changed oil and filter every 25 hours (twice a year - spring and fall). I've also put a new alternator and vacuum pump on it. I have been putting 50-60 hours per year on it but as you can see, it's only had an average of 33 hours a year since overhaul.

I've been everywhere I can be with a borescope and have seen no problems. There are no external cracks.

The airplane has always been kept in an enclosed, environmentally controlled hangar and I think this isn't discussed as much as it should be but is probably one of the biggest contributors to engine longevity.

I can't speak to 2000 hour TBOs but I personally believe that 12 years is a number designed to increase business for overhaul shops. I trust my engine a lot more than I would a recently overhauled one and am in no hurry to get it overhauled.
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I've been farmiliar with this one for about 7 years now. Our experience mirrors yours. When #4 came off last year there was no signs of corrosion on any internal engine parts, not like the varieasy driver that bought his from a coastal florida base. Remember that thread? Most corroded engine I've seen that was flying.

I really enjoy working cardinals. Probably the biggest PITA I've ran into is the lycoming oil suction screen or topping the nose strut with hydraulic fluid. Those tasks kinda suck lol.
 
JohnAJohnson said:
Brian, my O-360-A1F6D was last [field] overhauled in 1978 and now has 1200 hours on it. Last week at annual, all 4 cylinders were 79/80. There has never been any metal in the filter, and the engine pulls the plane at book speeds and fuel burns, so it's making book power.

Since I bought the plane in 2009 I've done a wobble test on the valves (they were and are fine), overhauled the Marvel carb, IRAN'd the D-3000 magneto, changed the rubber intake pieces, and have changed oil and filter every 25 hours (twice a year - spring and fall). I've also put a new alternator and vacuum pump on it. I have been putting 50-60 hours per year on it but as you can see, it's only had an average of 33 hours a year since overhaul.

I've been everywhere I can be with a borescope and have seen no problems. There are no external cracks.

The airplane has always been kept in an enclosed, environmentally controlled hangar and I think this isn't discussed as much as it should be but is probably one of the biggest contributors to engine longevity.

I can't speak to 2000 hour TBOs but I personally believe that 12 years is a number designed to increase business for overhaul shops. I trust my engine a lot more than I would a recently overhauled one and am in no hurry to get it overhauled.
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It is the number one factor contributing to the longevity and good condition of the entire plane including the engine IMO. You can immediately tell the difference between a plane that lived in a hangar its whole life and one that spent significant time tied down outside. A hangar doesn't prevent the big expenses, but it sure slows down their frequency. The big thing is all the nickel and dime stuff, especially in avionics, that it prevents.
 
It's not the purchase price but the maintenance costs for overhaul, etc that is expensive.
 
skynewbie said:
It's not the purchase price but the maintenance costs for overhaul, etc that is expensive.
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They are not wholly unrelated. A premium quality aircraft will not eat as much money as a bottom market aircraft, typically you are better off spending more up front.
 
Checkout_my_Six said:
time Tom.....It takes time to prove out infant mortality failures.

Anything beyond the first 100-200 hrs should be good to go....but, if something isn't assembled or manufactured correctly you'll know within this period.:wink2:

From a reliability standpoint....I want all my parts to be old, real old, cause most if not all core steel parts have infinite life on the S-N diagram. Now, aluminum cylinder heads.....not so much, I'd like new ones every time.
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I'll take a brand new engine over a used one any day.

Every part in the engine is new and meets new standards, and it has 10 hours of test cell run time on it prior to preservation and shipping. It is a no brainer that with common care it will go to TBO, then pass the size standards for service limits.

Otherwise the factory would never Warrantee it to TBO.
 
Checkout_my_Six said:
BTW....cranks typically do not fail within a TBO period and yes even the bad ones with the horrible ADs. They can last 6,000-10,000 hrs.....and when replaced are done so due to wear....not catastrophic failure.:rolleyes:
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If that is true, why do I see so many mid-time engines in the salvage yards with busted cranks?
 
Fearless Tower said:
If that is true, why do I see so many mid-time engines in the salvage yards with busted cranks?
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I'm only familiar with rare crank failures that are materials issues. Most frequently cranks break because excessive outside forces outside design limits were applied.
 
Henning said:
I'm only familiar with rare crank failures that are materials issues. Most frequently cranks break because excessive outside forces outside design limits were applied.
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He may be seeing the cranks that were destroyed at salvage in fear they might get used again.
 
Henning said:
They are not wholly unrelated. A premium quality aircraft will not eat as much money as a bottom market aircraft, typically you are better off spending more up front.
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Pay me now or pay me later.
 
Tom-D said:
I'll take a brand new engine over a used one any day.

Every part in the engine is new and meets new standards, and it has 10 hours of test cell run time on it prior to preservation and shipping. It is a no brainer that with common care it will go to TBO, then pass the size standards for service limits.

Otherwise the factory would never Warrantee it to TBO.
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and how do you know there aren't any defects within the assembled parts? 10 hrs of run time isn't enough time to prove that out. :no:
 
Fearless Tower said:
If that is true, why do I see so many mid-time engines in the salvage yards with busted cranks?
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I think we need more information than that.....engine make and model....and engine time.;)

It's not uncommon for cranks to go second, third, or even forth run OH. If those cranks had a catastrophic failure mode....there'd be ADs on them. The fact is cranks just don't catastrophically fail....they wear and become decommissioned.
 
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Fearless Tower said:
If that is true, why do I see so many mid-time engines in the salvage yards with busted cranks?
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Depends on vintage. A lot of old style cranks can fail around 8,000ish hours (give or take a few thousand). That's easy for an old crank to reach.
 
Ted DuPuis said:
Depends on vintage. A lot of old style cranks can fail around 8,000ish hours (give or take a few thousand). That's easy for an old crank to reach.
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if this were so you would think cranks would be a life limited part, but, they aren't. :wink2:
 
You guys new to flying? Did you miss the VAR crank issues in the 90s? The subsequent TCM crank recalls? And not long after that the Lycoming crank problems? I had a factory engine condemned for a crank issue. My plane sat on the ground for nearly 3 months to fix it. Alaskan summer months. That sucked.

Factory engines are my last choice when shopping for engines. The last two factory motors I bought both failed very quickly and had to be replaced. I built my most recent engine to new tolerances with balanced parts and flow-matched cylinders. That was a fun project and the engine is fabulous. It's smoother and more powerful than the factory engines my friends bought at the same time.
 
Reasons why I like a factory/name brand motor within TBO:

Pilot are cheap to a fault. They will fly 100 miles to save a nickel on gas. If I am buying an airplane, I want an engine with a proven pedigree.

Ignoring TBO is ignoring thousands of hours of engineering, materials science, etc. Sure some get away with it, but there are plenty that don't.

Factory/name brand engines with less than ~1,000 hours are the only things that increase the value of the aircraft. A&P motors, high time, etc. are all valued as run outs when it comes to resale.

While your A&P may be a master engine builder and a legend among local pilots. It won't matter to a buyer from across the country who has never heard of him.

Last playing the odds. I am not going to be comfortable flying an over TBO engine that I have no/limited history on in challenging conditions. I have no desire to find out exactly how far I can push a motor with low IMC and dense urban sprawl down below. So unless I have a long history with a motor and lots of data to back it up, it's going in for an overhaul.
 
Checkout_my_Six said:
if this were so you would think cranks would be a life limited part, but, they aren't. :wink2:
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I haven't seen any LLPs in the piston world, unless retired by AD.
 
Checkout_my_Six said:
so....there ya have it. :D:goofy:
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Yep, much different than the turbine world where many parts are retired at specific intervals as part of certification. But, fatigue analysis is much more detailed on turbines.
 
Ted DuPuis said:
Yep, much different than the turbine world where many parts are retired at specific intervals as part of certification. But, fatigue analysis is much more detailed on turbines.
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Oh great.... Now this Ted guy is an expert on piston engines....:eek:.........:D
 
Checkout_my_Six said:
and how do you know there aren't any defects within the assembled parts? 10 hrs of run time isn't enough time to prove that out. :no:
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The defective part issues that would cause a catastrophic failure have for the very most part already are proven in 10 hrs. Wrist pins, rods and rod bolts are my big concern as they can lead to 'explosive' type failures with parts ejecting through the cowling. It doesn't take very long at all to prove them out.

Do I 'trust' a Factory New engine? Irrelevant, I trust my ability to survive and I trust they are insured.
 
NOpe....not so. :no:

Infantile failures....born out in the "bathtub" curve....is much longer than 10 hrs. 10 hrs is just not long enough for "typical" inclusions/occlusions in cast parts to grow cracks that produce a failure. :yes:
Henning said:
The defective part issues that would cause a catastrophic failure have for the very most part already are proven in 10 hrs. Wrist pins, rods and rod bolts are my big concern as they can lead to 'explosive' type failures with parts ejecting through the cowling. It doesn't take very long at all to prove them out.

Do I 'trust' a Factory New engine? Irrelevant, I trust my ability to survive and I trust they are insured.
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Checkout_my_Six said:
NOpe....not so. :no:

Infantile failures....born out in the "bathtub" curve....is much longer than 10 hrs. 10 hrs is just not long enough for "typical" inclusions/occlusions in cast parts to grow cracks that produce a failure. :yes:
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:dunno: Every engine I have lunched on the dyno has failed in the first three runs, YMMV.
 
N801BH said:
I must have been drinkin or something.....:D:D....:rofl:
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You need more 100LL exposure! :D

Does anyone have a picture of me walking around Gastons with a pitcher of blue Kool-Aid? Would've been 2009.
 
Ted DuPuis said:
We not only remember it, I guarantee we know more about it than you. ;)
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All I know is what's happened to myself and my circle of friends. I have to snicker at many of the expert comments. Like how cranks don't fail. Clearly that isn't true, and it certainly hasn't been true for me. I'll stay away from factory motors and the common notion that they're somehow superior to other overhauls that use better than factory tolerances. Power and reliability are my priorities. As opposed to limiting liabity and maximizing profits. To each their own.
 
Henning said:
:dunno: Every engine I have lunched on the dyno has failed in the first three runs, YMMV.
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I know of one aircraft engine that was assembled without a wrist pin plug. Took 500 hours for the resultant catastrophic failure.

Sixy has it right.
 
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