So how bad is the used Aircraft sales

Read post 22 again, I did not say I recommend TBO be used.

I have a 0-320 in work now, the customer ran it near 3000 hours but in the last 100 hours it lost compression in 1 cylinder and the oil consumption increased greatly, and it was not making power it should. It went quickly when it reached its limit.

The customer knew the engine had no old parts that would be usable again so, the engine is toast, Charley Malot, built a replacement engine using a superior engine kit, and old data tag and appliances.and it will be on this month.

I'm saying you run past TBO you can expect to replace many more parts than if you rebuild at TBO. that is why Lycoming and continental both set there TBOs at a number where they expected the old engine parts could be re-used by servicing in the proper manner.

You can only regrind these parts a certain amount, you wear them beyond that you are going to buy new. and in today parts market that will get expensive quickly.
 
Tom-D said:
do not short hop any engine, run it long enough to get the water out of the crank case,
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And how does that differ significantly from "running it regularly"? Engines that get used a lot last more hours. Even flight school engines that get abused by students. Period.
 
Tom-D said:
Read post 22 again, I did not say I recommend TBO be used.

I have a 0-320 in work now, the customer ran it near 3000 hours but in the last 100 hours it lost compression in 1 cylinder and the oil consumption increased greatly, and it was not making power it should. It went quickly when it reached its limit.

The customer knew the engine had no old parts that would be usable again so, the engine is toast, Charley Malot, built a replacement engine using a superior engine kit, and old data tag and appliances.and it will be on this month.

I'm saying you run past TBO you can expect to replace many more parts than if you rebuild at TBO. that is why Lycoming and continental both set there TBOs at a number where they expected the old engine parts could be re-used by servicing in the proper manner.

You can only regrind these parts a certain amount, you wear them beyond that you are going to buy new. and in today parts market that will get expensive quickly.
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So I'm not an engine guy, please excuse my ignorance.

If we run the engine 500 hours past TBO and that causes the crank to be unusable, but the crank could have been used 500 hours ago, wouldn't that imply that 500 hours after the rebuild the crank would be in the same "bad" state?
 
jesse said:
So I'm not an engine guy, please excuse my ignorance.

If we run the engine 500 hours past TBO and that causes the crank to be unusable, but the crank could have been used 500 hours ago, wouldn't that imply that 500 hours after the rebuild the crank would be in the same "bad" state?
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No, in the case as you described, the crank was repairable to a authorized under size, fitted with new bearings and is good to go to TBO again.

You wait until 500 hours after TBO and the crank is ruined by any other failure so that it can not be repaired to an under size, you lost the crank. this often happens to a rod bearing failure.

Manufacturers make under sized bearings, but the crank must be in a condition as to be reground to the size required to fit the bearings available.

go beyond that, there are no bearings to fit it.
 
The decision to go beyond TBO is a study of each engine, do you have a first run engine with known good parts, or do you have an engine that is second run or beyond, and you know that the crank and cam set are going to be thrown away at overhaul?

If you have a first run factory engine that you can expect to save the crank, and other parts, why would you want to ruin them by running way beyond TBO.
 
Tom-D said:
The decision to go beyond TBO is a study of each engine, do you have a first run engine with known good parts, or do you have an engine that is second run or beyond, and you know that the crank and cam set are going to be thrown away at overhaul?

If you have a first run factory engine that you can expect to save the crank, and other parts, why would you want to ruin them by running way beyond TBO.
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How much is the crank worth, on, oh say an O-470?
 
jesse said:
How much is the crank worth, on, oh say an O-470?
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My Continental parts dealer doesn't even stock them if that gives ya a clue..

its a matter of finding one, and paying what you must to get it and then inspect and repair as necessary.

I'd guess around 5k for a used good as removed, Superior doesn't make a new one, so you are at the factory to see if they have one, stand by for a hit to the wallet
 
Tom-D said:
My Continental parts dealer doesn't even stock them if that gives ya a clue..

its a matter of finding one, and paying what you must to get it and then inspect and repair as necessary.

I'd guess around 5k for a used good as removed, Superior doesn't make a new one, so you are at the factory to see if they have one, stand by for a hit to the wallet
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At a cost of $5k and the savings by running above TBO, I don't see why going past isn't a good deal.

How much is the core worth?

An old pilot (and A&P) once told me "engines are throw away". I was shocked :yikes:when I heard this.
 
Jaybird180 said:
At a cost of $5k and the savings by running above TBO, I don't see why going past isn't a good deal.

How much is the core worth?

An old pilot (and A&P) once told me "engines are throw away". I was shocked :yikes:when I heard this.
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5K is a used crank if you can find one..

the first mass produced Lycomings were throw away engines, then they started rebuilding them. just like the diesels of today. only now they life limit them on a the type certificate so you can't rebuild them..
 
Tom-D said:
that is why Lycoming and continental both set there TBOs at a number where they expected the old engine parts could be re-used by servicing in the proper manner.
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I have not observed that to be an influence in TBO.
 
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In the event of my engine, the crank is toast whenever we split the case anyway (it's an Airmelt). My past-TBO engine is running strong and smooth, not making any metal and has excellent compression. Last year, mechanic had to admit it looked "pretty much new" inside, and when he looked at the lifters, he said they looked like new, too.

I'm biding my time, thanky very much. Maybe one of these days, I'll find me a good 550.
 
SCCutler said:
Maybe one of these days, I'll find me a good 550.
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Does it have a 520 in it now?

A friend of mine bought a totally refurbed V-35B with the Colemill Starfire IO-550/4 blade Q-tip prop conversion. All I can say is WOW.
 
Tom-D said:
It was quoted in the SB setting TBO., but the wording has changed in 2009.

http://www.lycoming.textron.com/support/publications/service-instructions/pdfs/SI1009AU.pdf

Its now in the advertisement for rebuilt engines

http://www.lycoming.textron.com/engines/service/zero-time-rebuilt-engines.html
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You are confusing marketing with engineering. It's marketing's job to sell engines, and the claims they make may be correct, but may not be absolute or all-inclusive of all contingencies.

But the first publication (which is more engineering) you list says...

SI 1009AU said:
Because of variations in the manner in which engines are operated and maintained, Lycoming can give no assurance that any individual operator will achieve the recommended TBO.
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So you may not ever reach that TBO, even with a factory overhaul.

I understand your point, Tom, but it's not all-inclusive. I've seen a lot more people who have engines under TBO that need an overhaul for whatever reason than people who are over TBO. The ones who are over TBO I see usually change it because they decide "it's time," even without compressions, metal, etc. indicating as such.
 
SCCutler said:
In the event of my engine, the crank is toast whenever we split the case anyway (it's an Airmelt). My past-TBO engine is running strong and smooth, not making any metal and has excellent compression. Last year, mechanic had to admit it looked "pretty much new" inside, and when he looked at the lifters, he said they looked like new, too.
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Not uncommon. The 520s are good engines, I'm really happy with the two I fly.

I'm biding my time, thanky very much. Maybe one of these days, I'll find me a good 550.
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The 550s are good engines, too. A friend of mine had his F33A's 520 overhauled as a 550 when it came time for overhaul (he ran 400 over TBO and decided "it's time"). He's very happy with the results - does about 170-175 KTAS @ 14 GPH. Going higher up it loses a few kts and a few gph. Overall seems to burn about 1.5-2 gph at a similar MP and RPM as my 520s, but that makes sense. Neither have GAMIs.

Anthony said:
A friend of mine bought a totally refurbed V-35B with the Colemill Starfire IO-550/4 blade Q-tip prop conversion. All I can say is WOW.
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I'm not a big fan of the 4-bladed Q-tips on the Bonanzas, I think they look kinda silly. But, I don't own a Bonanza. :)

The Q-tips also have some operational concerns, as my recollection is that they don't allow for as much damage before needing to be replaced. Actually, my recollection is that they have zero tolerance for damage. A friend of mine has 3-bladed Q-tips on his T310R RAM conversion, and he said he's not thrilled with the props. He loves the conversion, though. Hartzell must have been pushing those props when all those STCs were being brought to market. I'd stick to a traditional prop, personally.
 
SCCutler said:
In the event of my engine, the crank is toast whenever we split the case anyway (it's an Airmelt). My past-TBO engine is running strong and smooth, not making any metal and has excellent compression. Last year, mechanic had to admit it looked "pretty much new" inside, and when he looked at the lifters, he said they looked like new, too.

I'm biding my time, thank very much. Maybe one of these days, I'll find me a good 550.
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That's the best reason I know of to run past TBO.. yer going to throw it away anyway.

The only real reason to overhaul in part 91 is you don't trust it anymore. but as I have said there are penalties for that.
 
Tom-D said:
http://www.lycoming.textron.com/support/publications/service-instructions/pdfs/SI1009AU.pdf
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Did you guys catch the recommendation of overhauling at 12yrs if the engine hasn't yet reached TBO. Do the math. For many airplanes, they would never reach those operating times.

I recall reading another SB that recommended a minimum operation of 4hrs per month, which I thought was reasonable to keep an engine healthy (assuming that the engine was flown 30 mins in cruise AFTER it had reached full operating temperature) I know a Mooney owner that does short 30 min hops. I have yet to (find again) or show him the SB.
 
Jaybird180 said:
Did you guys catch the recommendation of overhauling at 12yrs if the engine hasn't yet reached TBO. Do the math. For many airplanes, they would never reach those operating times.

I recall reading another SB that recommended a minimum operation of 4hrs per month, which I thought was reasonable to keep an engine healthy (assuming that the engine was flown 30 mins in cruise AFTER it had reached full operating temperature) I know a Mooney owner that does short 30 min hops. I have yet to (find again) or show him the SB.
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I don't believe time means anything to a chunk of iron..
 
Tom-D said:
I don't believe time means anything to a chunk of iron..
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CYA for seals, gaskets, and fuel lines. Reduction in liability for the company.... "Hey we told you to rebuild it at 12 years or 2000hrs......."

Don't heli's have parts that time-out (calender time) as well?
 
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