12 year recommended overhaul?

GBSoren

GBSoren

Pre-takeoff checklist
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GBSoren
In my quest for my first plane I'm learning something new every day. What I've been looking at are lower hour mostly early 2000's planes. Now I understand that the hours may not matter much because of the 12 year overhaul, even on a low houred motor.

So, my question is, do most live by this recommendation? Or, do you go more by the annuals and oil samples to determine when a OH is needed?
 
You will get a variety of opinions on this. My take is that the 12 yr. recommendation is not important unless the plane has had periods of inactivity. Extended inactivity is a red flag itself, independent of the years since overhaul or hours since overhaul. So I would say the 12 yr. thing is not important in and of itself. Some engines seem to be more prone to expensive corrosion problems than others (so I hear).

How do you determine if the plane has sat for months at a time? Talk to the owner, and previous owners if you can, and examine the logbooks for intervals without much change in tach time.
 
I had a 1973 Decathlon with 600 hours and never overhauled. It was fine. I sold it and new owner is still flying it.
 
I'm with David and Pigpen on this issue.
 
The twelve years is a recommendation,if you fly the plane on a regular basis and keep it well maintained,should not be a problem going to Hourly TBO. At 100 hrs a year your just over half the engine life.
 
Unless it's a Lycoming with the crankshaft AD. If that's the case then 12 years is it.
 
The Continental A65 in my antique taildragger was last overhauled in 1981 and has less than 1000 hrs on it. I see no reason to overhaul it as long as it's running well.

I'd be willing to bet that less than 1% of owner flown airplanes have their engine(s) overhauled just because the calendar TBO limit is reached.

And while the operating hour TBO is at least loosely based on mechanical wear, AFaIK the calendar TBO is almost purely arbitrary.
 
pigpenracing said:
If there is a crankshaft AD it is grounded right away and can't fly...
Click to expand...

Nope, it's good until torn down for any reason or 12 years at which time it has to be replaced. I know, sounds strange but that's the AD. 2012-19-01
 
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GBSoren said:
In my quest for my first plane I'm learning something new every day. What I've been looking at are lower hour mostly early 2000's planes. Now I understand that the hours may not matter much because of the 12 year overhaul, even on a low houred motor.

So, my question is, do most live by this recommendation? Or, do you go more by the annuals and oil samples to determine when a OH is needed?
Click to expand...

If it's for pt91 ops don't worry about the 12 year crap.

Have a good pre buy done and go from there.
 
The 12 year thing is just a liability game by their lawyers.

But an engine that is 12 years old and below TBO didn't fly much more than 100 hours a year on average and probably does have large gaps in usage in those 12 years.
 
Silvaire said:
Nope, it's good until torn down for any reason or 12 years at which time it has to be replaced. I know, sounds strange but that's the AD. 2012-19-01
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There were a bunch of Pitts S-2C's and other aerobatic planes with 540's that had a crank AD.... They were grounded. I had one just a few years old with 25 hours on it and the crank had to come out!
Cranks could not go after 2009. My Pitts was a 2003 model
http://www.aopa.org/Advocacy/Regula...ulatory-Brief-Lycoming-Crankshaft-Replacement
 
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Manifesto One author's opinion regarding your question.
The kindle book is free right now. (If you have an ipad, you can get a free account to download it). [You do not need the kindle app but it is free too]
 
I was squarely in the camp of "the amount of time isn't very important" until I saw my engine come apart last month and got a close look at the guts.

Now I'm leaning the other way.

My engine was a mess after 12 years and I tried hard to do everything right to keep rust out of it. And I'm not in an extremely damp environment like the SE.

That said, if I lived in Phoenix then I'd be far less concerned about time.
 
12 years may not be grounds for condemnation in Part 91 but it isn't a value added feature, either. Adjust the value of your airplane purchase accordingly.

Here's Cessna's corrosion map for North America if it interests you at all. where an infrequently used airplane lived it's years would be a consideration if I was considering buying it.
 

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I scored a really nice deal on my IFR Cherokee 180 C. It had mid time hours (1000 hours on the engine that was rebuilt in the late 90's.) It was flown regularly and had very nice detailed logs.. It did sit for about a year or so the year before I bought it due to the previous owner upgrading it and not needing it. I was concerned at first but found nothing wrong with going forward.. I plan to at least keep this through the next overhaul so I am fine with it. I have put about 160 hours on it since April and have not had any issues at all with the engine.

Just look for rust if it has sat for a long time is my take on it.. oh and the hoses are important too :) I fly it atlas 2-3 times a week but I did start putting Cam Guard in it after reading all the data points on rust prevention..
 
My 520s were 17 years old when pulled apart. They looked perfect inside.

I don't overhaul based on hours or years, look for indications of a problem. I'm hoping for 3000 hours out of these engines.
 
Crank may not be an issue, but trying to figure out the Oil Pump Gear AD on an older engine may also prove challenging.
 
I'd wait for the engine to talk to you before tearing into it.....:yes:

How does an engine talk back?

* low oil pressure
* high oil consumption
* metal in the filter
* metal in the sump
* metals in the oil analysis
 
Ted DuPuis said:
My 520s were 17 years old when pulled apart. They looked perfect inside.

I don't overhaul based on hours or years, look for indications of a problem. I'm hoping for 3000 hours out of these engines.
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Good facts.........:yes:
 
Checkout_my_Six said:
I'd wait for the engine to talk to you before tearing into it.....:yes:

How does an engine talk back?

* low oil pressure
* high oil consumption
* metal in the filter
* metal in the sump
* metals in the oil analysis
Click to expand...

I know of one that is 47 years old. I watch the oil filter and suction screens carefully. Even the old mags and carb never let me down but did get replaced a few years ago and it runs a whole lot smoother.

My 13 year old car runs worse and has "broke down" (not started) more than once... <cough> two new fuel pumps.
 
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My take on it is...

Don't overhaul an engine based on time, as others have said, just listen to what it's tell you (compressions, oil analysis, filter cut, etc.)

But...

if buying a plane with an engine that was OH'ed over 12 years ago...price it as run-out regardless of how many hours since major. It's a crap shoot.
 
timwinters said:
My take on it is...

Don't overhaul an engine based on time, as others have said, just listen to what it's tell you (compressions, oil analysis, filter cut, etc.)

But...

if buying a plane with an engine that was OH'ed over 12 years ago...price it as run-out regardless of how many hours since major. It's a crap shoot.
Click to expand...

I've said before every engine is different. When the engine has not been started in a long time, I often advise to tear them down, inspect, and try to save a bad/corroded part from destroying or contaminating the rest of the engine.
When electrolysis has caused a pit in a lifter face it will destroy the cam when started, the debris from that will destroy the crank, and in some cases contaminate the prop.
It's a gut feeling call, but it is much easier to tear it down and really know what the condition really is than to allow the engine to trash its self.
 
gismo said:
The Continental A65 in my antique taildragger was last overhauled in 1981 and has less than 1000 hrs on it. I see no reason to overhaul it as long as it's running well.

I'd be willing to bet that less than 1% of owner flown airplanes have their engine(s) overhauled just because the calendar TBO limit is reached.

And while the operating hour TBO is at least loosely based on mechanical wear, AFaIK the calendar TBO is almost purely arbitrary.
Click to expand...

I agree. Three or four of mine, t crafts , champ, Stearman all were in this catagory, ran fine and had very decent compression. The Stearman had an in flight problem causing a forced labding but it was improper valve setting by lousy mechanic. I agree that many many would be needlessly grounded if this rule were followed as long as good maintence is observed including 25-30 hour oil changes,never if you have a filter.
 
Should be corrected to ......even if you have a filter. Apple often makes incorrect assumptions .
 
Depends. If I'm buying, yes, the calendar TBO would matter to me, and affect my offer. 1,000 hours and 25 years old? Yeah, that's a lot time for condensation, corrosion, freeze-thaw. I don't know enough about the innards. . .

But if I owned it, had hands on, felt like it was in good shape, and my mechanic agreed, the the calendar wouldn't matter too much to me.
 
Stewartb said:
12 years may not be grounds for condemnation in Part 91 but it isn't a value added feature, either. Adjust the value of your airplane purchase accordingly.

Here's Cessna's corrosion map for North America if it interests you at all. where an infrequently used airplane lived it's years would be a consideration if I was considering buying it.
Click to expand...

Is this map available for other parts of the world? Europe, UK, Ireland, in particular.
 
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