She's been a sitter, probably needs a Top Overhaul??

DKirkpatrick

DKirkpatrick

Pre-takeoff checklist
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DKirkpatrick
Hello. Looking at an airplane that looks like it's been a sitter for a long time.
IO-360... pulls through, has oil in it.
Oil smells like oil, nuthing funky.
Has about 1400 hrs. SFOH

Anybody know the cost to do a top overhaul on an engine like this? I'm trying to build a budget...
I'm betting the bottom is okay.
THANKS!
 
The cam is what you should be worried about. Topping doesn't deal with that.
 
Stewartb said:
The cam is what you should be worried about. Topping doesn't deal with that.
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Not just the cam. If the owner has been ground-running it without flying it, it will have corrosion in the cylinders and on the gears and everywhere. Water is a byproduct of combustion, and water vapor gets past the piston rings as part of the blowby when the engine is cold, condenses in the case, reacts with the oil in the presence of metals, and forms several nasty acids. I work full-time on light airplanes and see this far too often. It's sad, the way some owners think they are helping the engine by doing this. That engine needs to get hot for an hour or so to boil the accumulated moisture off, and the engine needs to be put away hot.
 
Like others have said, I would bet the cam goes before the cylinders. You said it has been sitting a long time--how long? What part of the country?
 
Hey THANKS for the feedback. Been in a dry part of the world, in a big, enclosed hangar for about six years. I think it was an old man that just owned it and quit flying...
Just trying to figger the cost to get it flying. I know these engines routinely make TBO if they're flying... which means they're good engines to start with... but some valve, somewhere has been open for six years... which has gotta mean humidity inside the engine somewhere...
I'm willing to gamble some on the airplane, but a major would be tough to swallow...
 
DKirkpatrick said:
Hey THANKS for the feedback. Been in a dry part of the world, in a big, enclosed hangar for about six years. I think it was an old man that just owned it and quit flying...
Just trying to figger the cost to get it flying. I know these engines routinely make TBO if they're flying... which means they're good engines to start with... but some valve, somewhere has been open for six years... which has gotta mean humidity inside the engine somewhere...
I'm willing to gamble some on the airplane, but a major would be tough to swallow...
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I'd suggest you simply pull some cylinders and find out what condition the cam is in prior to ruining it, so it can't be reground. you'd probably save a few lifters too. and possibly the crank, if the debris get's into the oil system.
 
Stewartb said:
The cam is what you should be worried about. Topping doesn't deal with that.
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but when he pulls the cylinders to top them he will see the cam and lifters.
 
Some of this sitting destroys everything stuff is mostly a OWT, so long as the owner did just a hair of preventive MX.

Frankly, unless you're buying a new airplane, with the average age of the fleet, if your plane doesn't have over 10,000hrs; it's been "sitting" for a while too.

Just do a good prebuy like anything else.
 
To actually be the first person to answer the OP's question, after 10 non-answering replies...

$1000 per cylinder.
 
why buy a sitter? Spend the extra $5-8k and get an airplane that will not have mouse nests, filth and a bad motor - its gonna cost $10k for top rebuild and then you still need to deal the rest of the funk -
 
Unless you are an A&P and have the time and drive to do a project plan, it is better in most cases to pass. Also, for many, time is money.
 
Everyone i know that took a gamble on a plane sitting a few years had serious engine issues to contend with. May have better luck from a dry climate, but seals can go bad too. Each cylinder is about $1000 and dont forget to add some labor.
 
Blueangel said:
Unless you are an A&P and have the time and drive to do a project plan, it is better in most cases to pass. Also, for many, time is money.
Click to expand...

Tell me why you need to be an A&P to do a project plan(e)? Yes, time is money, unless you like working with your hands for relaxation and fun time after you make your money.

Jim
 
DKirkpatrick said:
Hello. Looking at an airplane that looks like it's been a sitter for a long time.
IO-360... pulls through, has oil in it.
Oil smells like oil, nuthing funky.
Has about 1400 hrs. SFOH

Anybody know the cost to do a top overhaul on an engine like this? I'm trying to build a budget...
I'm betting the bottom is okay.
THANKS!
Click to expand...

It will most likely need a cam if not more than that. You may get lucky but odds are not in your favor. Other things to consider are the electronics and fuel system. Gyros do not like to sit for long periods and will likely need overhaul and potentially other electrical components. If it has wet wings or fuel bladders they will likely need attention as well as fuel lines and oil lines, tires and tubes.
 
DKirkpatrick said:
... but some valve, somewhere has been open for six years... which has gotta mean humidity inside the engine somewhere...
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So many miss the point. Local humidity plays a role, certainly, but I have seen engines that have sat for years without running, opened them up, and they were fine. Those that were ground-run were a mess.

From this http://www.flyingmag.com/aircraft/pistons/piston-engines-keeping-your-cylinders-happy

...we read: A healthy engine requires frequent use. The general consensus is that you need to fly at least once a month. While some people believe it’s sufficient to pull the airplane out of the hangar, start it up and run it for a few minutes, this can actually be detrimental. “The engine can’t get up to temperature on the ground, and all that moisture that was created during that ground run simply stays in the engine,” Palmatier said. Lycoming recommends flying a minimum of one hour, not including taxi, takeoff and landing, at oil temperatures between 165 and 200 degrees.

And here http://www.aviationpros.com/article/10387461/corrosion-how-does-it-affect-the-internal-engine

...we read: First let’s analyze where these elements necessary for corrosion originate. No. 1, moisture: When you burn a pound of fuel, you get about a pound of moisture as a result. Most of this is expelled out of the exhaust stacks but some enters the crankcase via "blow by." Some moisture comes from the air that the engine takes in through intake and it is mixed with the combustion moisture. One other minor source is the moisture in the air that is drawn in through the engine breather tube as the engine cools after shut-down. The aircraft engine absorbs this moisture and doesn’t release it unless your oil temperature gauge gets over approximately 180 degrees F. If you have your oil temperature high enough, the moisture vaporizes and exits by way of the crankcase breather......When an engine oil is exposed to heat, a process called "oxidation" is started. When oxidized oil is mixed with moisture as discussed earlier it often forms an acid which attacks metal surfaces. This is a concern relating to certain sump pump preheaters which may overheat and degrade the oil as it heats the engine. Another problem with these heaters is that as they heat the oil, driving the moisture out, the vaporized moisture will rise and again condense on cooler parts of the engine. This condensed moisture will begin the corrosion process on that engine part.
 
Another classic thread on POA - Pilots Opposing Aircraft ownership.....


Yep, a guy wants to understand cost on cylinders, and he is advised he won't be able to afford the plane due to tires, mice, and marine mammals.
 
Hey thanks. I kinda agree with the "POA" above...
And I understand the cam is first to go... I was just assuming cylinders could/might be rusted and require replacing. And trying to figure a price for a top... ergo... fixes to engine, vs. a major OH.
Thanks — $1000/cylinder.
I appreciate the insight.
 
I wouldn't expect the cylinders to have any problems and I wouldn't expect you'll get a top for $4K.
 
shoot just put some MMO down the cylinder, fire it off, put a clear coat over the corrosion, yell out GYSOT and flip it for 10G profit !

they do it all the time on them there TeeVee shows
 
jaybee said:
shoot just put some MMO down the cylinder, fire it off, put a clear coat over the corrosion, yell out GYSOT and flip it for 10G profit !

they do it all the time on them there TeeVee shows
Click to expand...

Is that before or after you cinch the exhaust up with baling wire and use JB weld on that busted-off carburetor stud?

Jim
 
I never said he couldn't afford it - just that there will be nests, corrosion, flat spotted tires, bugs, dirt, grime and general crap from neglect all over the place - even if its kept up because you know what happens when something is not operated as intended. I don't care what it is. . . . go look on a ramp or into hangars at any airport in the country.

My comment is based on a) time is money and b) he's buying a plane not a project. you want to FLY the damn thing - and if its in the shop the first 3 months - that definitely affects the joie de vivre of owning - esp if you want to fly and need to still rent AND pay a mechanic to fix things -

Find a flown well-kept example of the same airframe - who CARES if its 1000 miles away - it flies and can go places on its own.
 
For a aircraft stored indoors and cared for, no
 
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It is not just the cost of the cylinders but the labor cost and accesories that often need to be replaced at same time. You either need an A&P friend to help do the work or owner assisted work.
 
Why not do this?

Find the same model plane that is used regularly and has similar hours, then offer the guy that has the plane you want 15k less and see if he bites. Worst case you need an over haul and the other plane flies until TBO, but in the case of the plane that you offered 15k less, that 15k goes towards the overhaul of a new engine.
 
midcap said:
Why not do this?

Find the same model plane that is used regularly and has similar hours, then offer the guy that has the plane you want 15k less and see if he bites. Worst case you need an over haul and the other plane flies until TBO, but in the case of the plane that you offered 15k less, that 15k goes towards the overhaul of a new engine.
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And how do you know the jugs on the plane flown everyday won't need to be replaced. So folks would be better off if they never touched their planes

This whole topic reminds me of this ;)

image.jpg
 
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James331 said:
And how do you know the jugs on the plane flown everyday won't need to be replaced. So folks would be better off if they never touched their planes

This whole topic reminds me of this ;)
tealeafreading1.jpg
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lol...what is that? flies to honey?

You are right thought....it almost seems to make sense just to buy a timed out plane, hope for another 100 hours and then overhaul. I would be royaly ****ed if I bought a plane that had a low/mid time engine and then had to over haul it shortly after purchase.
 
comanchepilot said:
I never said he couldn't afford it - just that there will be nests, corrosion, flat spotted tires, bugs, dirt, grime and general crap from neglect all over the place - even if its kept up because you know what happens when something is not operated as intended. I don't care what it is. . . . go look on a ramp or into hangars at any airport in the country.

My comment is based on a) time is money and b) he's buying a plane not a project. you want to FLY the damn thing - and if its in the shop the first 3 months - that definitely affects the joie de vivre of owning - esp if you want to fly and need to still rent AND pay a mechanic to fix things -

Find a flown well-kept example of the same airframe - who CARES if its 1000 miles away - it flies and can go places on its own.
Click to expand...
If I had that attitude, I would not have an airplane to fly. No way I can afford $30k up front for an airplane. But I can swing $15k for a flying example that needs work. Then spend the next 3 to 6 months to end up with a better airplane than I could buy for $30k, and have only $25k in it.
YMMV.
 
Dan Thomas said:
Not just the cam. If the owner has been ground-running it without flying it, it will have corrosion in the cylinders and on the gears and everywhere. Water is a byproduct of combustion, and water vapor gets past the piston rings as part of the blowby when the engine is cold, condenses in the case, reacts with the oil in the presence of metals, and forms several nasty acids. I work full-time on light airplanes and see this far too often. It's sad, the way some owners think they are helping the engine by doing this. That engine needs to get hot for an hour or so to boil the accumulated moisture off, and the engine needs to be put away hot.
Click to expand...

I've seen the same on engines that haven't been ground run...

I'm currently overhauling an IO-540 off an Aztec that was last overhauled in 1988 and has accumulated 700 hours since then. For the last 15 or so years the previous owner was only using the airplane once or twice a year, accumulating about 5 hours per year flight time on average. A friend bought it 1.5 years ago and we started regularly flying it and guess what happened? About 100 hours into ownership both engines are in need of repairs. I opened up this engine and every steel part in it except the crank was almost completely brown with rust. I cringed sending in the parts for cleaning and inspection but thankfully most came back ok. Hopefully this time around the usage will be high enough to avoid the same problem happening again. Or, if it does happen again it probably won't be to my friend. It will be interesting to see what engine #2 looks like after I open it up.
 
mondtster said:
I've seen the same on engines that haven't been ground run...

I'm currently overhauling an IO-540 off an Aztec that was last overhauled in 1988 and has accumulated 700 hours since then. For the last 15 or so years the previous owner was only using the airplane once or twice a year, accumulating about 5 hours per year flight time on average. A friend bought it 1.5 years ago and we started regularly flying it and guess what happened? About 100 hours into ownership both engines are in need of repairs. I opened up this engine and every steel part in it except the crank was almost completely brown with rust. I cringed sending in the parts for cleaning and inspection but thankfully most came back ok. Hopefully this time around the usage will be high enough to avoid the same problem happening again. Or, if it does happen again it probably won't be to my friend. It will be interesting to see what engine #2 looks like after I open it up.
Click to expand...

Short flights will do it, too.
 
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Dan Thomas said:
Short flights will do it, too.
Click to expand...

Your luck has been better than my experiences, if the only time you've been seeing rust is on ground run and short flight engines. Every engine I've overhauled so far has had rust in it, the amount just varies. (Note that I only work on privately owned and operated low use airplanes, no flight school or 135 type stuff.) The worst I saw was an O-320 off an airplane that sat outside, out of annual for the better part of a decade without being run. The cleanest I've seen was the one I would have expected to be one of the worst, which is on a ratty old float plane that is used infrequently but primarily run on car gas. This Aztec engine was bad, but no comparison to the aforementioned O-320.

So, how does all this discussion relate to the OP? I'd say go into the engine inspection with an open mind. It may be perfectly fine and or it may be a mess. It is probably something somewhere in the middle of the two extremes. You really won't know much of anything until you open it up.
 
Also be careful you don't fly too much, you'll hit TBO and you'll have to rebuild as well :mad:

If you let your airplane sit the wings will fall off and rats will live in it, if you fly it everyday you'll get too many hours and no one will buy it because it's go too many hours and the wings will fall off :mad:

Better to just take up golf lol
 
DKirkpatrick said:
Hey thanks. I kinda agree with the "POA" above...
And I understand the cam is first to go... I was just assuming cylinders could/might be rusted and require replacing. And trying to figure a price for a top... ergo... fixes to engine, vs. a major OH.
Thanks — $1000/cylinder.
I appreciate the insight.
Click to expand...
Rusty cylinders usually simply get honed and a new set of rings and they are good to go.
AS for cost? ask your A&P we don't know what they charge.
 
bluerooster said:
If I had that attitude, I would not have an airplane to fly. No way I can afford $30k up front for an airplane. But I can swing $15k for a flying example that needs work. Then spend the next 3 to 6 months to end up with a better airplane than I could buy for $30k, and have only $25k in it.
YMMV.
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if you have time instead of money - and are licensed to do your own work - then sure. Anyone in that situation can buy a fixer upper - not much motor and airframe work you can do yourself to a non-experimental without an A&P. . . or at least someone to sign it off.
 
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comanchepilot said:
if you have time instead of money - and are licensed to do your own work - then sure. Anyone in that situation can buy a fixer upper - not much motor and airframe work you can do yourself to a non-experimental without an A&P. . . or at least someone to sign it off.
Click to expand...
Why not get an A&P mentor who will supervise what you do?
 
Dan Thomas said:
Not just the cam. If the owner has been ground-running it without flying it, it will have corrosion in the cylinders and on the gears and everywhere. Water is a byproduct of combustion, and water vapor gets past the piston rings as part of the blowby when the engine is cold, condenses in the case, reacts with the oil in the presence of metals, and forms several nasty acids. I work full-time on light airplanes and see this far too often. It's sad, the way some owners think they are helping the engine by doing this. That engine needs to get hot for an hour or so to boil the accumulated moisture off, and the engine needs to be put away hot.
Click to expand...
So.... How would one know if they have rusty cams, cranks, gears and etcetera? Is there some kind of tell or is it know post-failure?
 
comanchepilot said:
if you have time instead of money - and are licensed to do your own work - then sure. Anyone in that situation can buy a fixer upper - not much motor and airframe work you can do yourself to a non-experimental without an A&P. . . or at least someone to sign it off.
Click to expand...
I'd guess that all this time=money talk is by people who make much more per hour. For you I couldn't agree more. Bill Gates couldn't afford to pickup $1000 bills he dropped on the ground. For the rest of us plebes, time really isn't that much about money. For those that want to take a chance on a sitter, it likely isn't at all.

If I buy a $20k sitter and put 5K into jugs and spend 200 hours fixing it up at $20/hr, I'm all-in for $@30k and should know what I've got. But the same deal at $250/labor hr is now a $75,000 spruced up sitter. Isn't the same thing is it?
 
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