Crashed Engine

Mtns2Skies

Final Approach
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Mtns2Skies
EDIT: Disregard - engine was sold before I could even call.

I'm considering buying the engine that came out of this plane in order to have a spare on hand to get overhauled so my plane won't be down for the better part of a year when it's due for an overhaul.

I'm going into it assuming the crank is trash. Given this level of damage - is it even worth considering the case & cylinders being salvagable?
290886605_2204300859725018_1416281028215632430_n.jpg
http://www.kathrynsreport.com/2019/11/cessna-182m-skylane-n91846-incident.html
 
Last edited:
Millenniums may require replacement at overhaul. Check the SNs. Crank may be okay. Case, too. You’ll send them out for machining anyway, right? Get them inspected and tagged, and hope the tag isn’t red.
 
Offer a price that’s contingent upon successful inspection of major components (it does look like it landed on the prop so the case & crank etc are all highly suspect)
 
Looks like a nosewheel collapse and flip. I've seen much worse.
 
Rebuildable core values are strong. I doubt that’s rebuildable.
 
You guys must not see many nose-overs. Nothing there indicates engine damage other than a power-off prop strike in what must have been pretty loose soil.
 
You guys must not see many nose-overs. Nothing there indicates engine damage other than a power-off prop strike in what must have been pretty loose soil.
I dunno. The whole weight of the airplane came against that prop, and I'd expect the possibilities of a bent crank, cracked case, and maybe cracked engine mounting lugs. There's a bit of curl on the RH blade, indicating at least a bit of power on when it hit. The engine mount itself appears to be bent downward, and those mounts are good for 9G vertically.
 
Cases and cylinders are not big ticket items.

Crankshafts and cams are where you run into trouble and the biggest ticket items.

Having a motor rebuilt and pickeled 'just in case'? Invest that money and buy new at overhaul. You do realize that you have to service a pickled engine every 6 .onths or so otherwise the protective coatings run off the metal.
 
Cases and cylinders are not big ticket items.

Crankshafts and cams are where you run into trouble and the biggest ticket items.

Having a motor rebuilt and pickeled 'just in case'? Invest that money and buy new at overhaul. You do realize that you have to service a pickled engine every 6 .onths or so otherwise the protective coatings run off the metal.
There have been unpickled engines sitting in dry basements for 30 years without corrosion. My own A-65 sat in an unheated workshop next to a swamp for about six years without corrosion. Most corrosion is caused by combustion blowby gases, not environmental moisture, and storage oil is intended to isolate that stuff from the metal and not form acids with it. Flying that engine hard for an hour or more and putting it away hot is the best way to avoid corrosion.

The OEMs' recommendation to repickle engines is more of a CYA thing. They run them on the test stand after overhaul and then pickle them. They haven't been run long enough and hard enough to get the moisture out. All the factory Lycs I bought had only 20 minutes of run time on them, and that's with new rings and bores, so lots of blowby. They filled the cylinders with oil, quarts of it, and lots more in the crankcase.
 
20 minutes? My run report is a full 60 minutes. And Lycoming said the engine as shipped filled with oil required commissioning within 60 days, I think. That may be wrong but it wasn’t very long. They do not ship engines “pickled.”
 
20 minutes? My run report is a full 60 minutes. And Lycoming said the engine as shipped filled with oil required commissioning within 60 days, I think. That may be wrong but it wasn’t very long. They do not ship engines “pickled.”
Yup mine said only protected for 60 days. Then like said already there was oil behind every plug and cover that poured out, a few quarts. I took delivery on a rainy day!! lol Not the best conditions.
IMG_7774.JPG
 
AD340FE0-1274-42A7-870A-A82D711A7DC7.jpeg If I am reading this right? It looks like my little 320 was run 30 minutes before I got it?
I would imagine there would be different run in periods for different engines?
 
Hold on! There is a second page. It looks like a total of a hour run time?
D243F6F4-F2CC-4BB7-9E46-6B58A85D469F.jpeg
 
Seems I recall reading somewhere that running the engine for one hour produces x amount of water. If that’s the case, how do you ever burn the moisture out completely? Is that true or internet hogwash?
 
X amount of water is a calculation of H2O produced by combustion but only a minuscule amount remains in the engine. Note that Lycoming adds hot oil before start-up. The oil is always above the moisture temp, but there has to be some moisture left in there after cool down condensation. That's likely why they fill the crankcase, induction, and cylinders full of oil to ship. It makes a big mess when you remove all the cover plates. Cessna used to deliver new airplanes with anti-rust oil that could be flown, like Phillips anti-rust. I use it for winter storage but have never done the desiccant plugs and bags in the exhaust. I did make a couple of simple engine dehydrators and there's no question they get the engine interior humidity below the rust level. Like 5% humidity in a 40% humidity environment. I'm pretty pleased with that.
 
Seems I recall reading somewhere that running the engine for one hour produces x amount of water. If that’s the case, how do you ever burn the moisture out completely? Is that true or internet hogwash?
Lots of short runs lets the water accumulate from run to run. Getting hot eliminates any condensed water and limits the water to the level of water in the blow-by right now.
 
I met an O-320 that was o/h and run in a test cell by a Major Shop a week earlier.

During shipping a Rocker Cover got dinged. When removed to see if there was damage the Cover had begun rusting already.
 
Lots of short runs lets the water accumulate from run to run. Getting hot eliminates any condensed water and limits the water to the level of water in the blow-by right now.

Not unless you remove the dipstick, I do this as SOP, water vapor can be seen escaping for 15 minutes.
 
Not unless you remove the dipstick, I do this as SOP, water vapor can be seen escaping for 15 minutes.
That doesn't get the water that has condensed in an engine after a brief run. It runs down and into the sump, under the oil. Corroded sumps are proof of that. It sits there and forms acids during electrolytic action with the oil, catalyzed by the metal, and later engine runs pump those acids into everything.
 
Seems I recall reading somewhere that running the engine for one hour produces x amount of water. If that’s the case, how do you ever burn the moisture out completely? Is that true or internet hogwash?

Most of it goes out the exhaust. You only need to deal with the moisture that blows by the rings. And much of that, at operating temperature, goes out the breather tube and onto the bottom of your plane.
 
There have been unpickled engines sitting in dry basements for 30 years without corrosion. My own A-65 sat in an unheated workshop next to a swamp for about six years without corrosion. Most corrosion is caused by combustion blowby gases, not environmental moisture, and storage oil is intended to isolate that stuff from the metal and not form acids with it. Flying that engine hard for an hour or more and putting it away hot is the best way to avoid corrosion.

The OEMs' recommendation to repickle engines is more of a CYA thing. They run them on the test stand after overhaul and then pickle them. They haven't been run long enough and hard enough to get the moisture out. All the factory Lycs I bought had only 20 minutes of run time on them, and that's with new rings and bores, so lots of blowby. They filled the cylinders with oil, quarts of it, and lots more in the crankcase.
Gravity is going to pull that coating off the surface it is supposed to protect

MILSPEC parts have repack dates from months to years depending on the preservation method.

Oils run off the quickest, greases usually last longer but its not CYA to have to reapply preservative. It simple means that the environment you are storing in is not as bad as it COULD be.

Luck is not the same thing as proper preservation techniques.
 
Gravity is going to pull that coating off the surface it is supposed to protect

MILSPEC parts have repack dates from months to years depending on the preservation method.

Oils run off the quickest, greases usually last longer but its not CYA to have to reapply preservative. It simple means that the environment you are storing in is not as bad as it COULD be.

Luck is not the same thing as proper preservation techniques.
Storage oils like Shell's 2XN are put into the engine, the engine is run--it can even be flown--to get the stuff into everything, then the top plugs are taken out and the cylinders fogged with it and the plugs reinstalled. The intake and breather are closed off. Now, tell me how environmental moisture is going to get in there and do any damage? Sure, gravity pulls the oil down but a film remains on the parts; that's what that oil is for, and a film is as good as an inch.

The REAL corrosion damage comes when owners ground-run their engines to "circulate the oil and coat everything." That introduces a lot of combustion byproducts, including water, that are all corrosive. The water forms at least three different acids as it reacts with the oil.

I once worked on a low-time 172 that had only 270 hours on it; the engine was corroded beyond serviceability because the owner had ground-run it instead of flying it. Had to install a new engine. I have done runups before scheduled inspections and found water in the rocker covers immediately after, and this was in engines that were flown hard every day. Mechanics are familiar with rust in those covers. Some of us are familiar with corrosion in magneto drives, too.

I have worked on engines that have sat for years, with no care or preservation at all, just left alone, no ground-running, and found them perfectly fine inside.

What is your experience with engine corrosion, engine storage and preservation, and maintenance?
 
Corrosion can be somewhat unpredictable as Dan said.

I met a Cherokee that had been sitting in a non- heated hangar for about 20 years. The mags had been removed. The hangar was about 200 feet from a river. The aircraft was up on jacks for WHEN (not IF) the river would flood.Pulled jugs off and never found any sign of corrosion. It’s been flying about 8 years and several hundred hours with no issues.

Flip side

Springs have ZERO tolerance for rust.

I installed an Impulse Coupling Spring on a Ercoupe Project to address a dead mag.
About a year later the Owner tells me irs acting the same. He had been ground running and taxi ops only. There was a spot of rust where the Spring broke.
Since then I immerse the assembled Coupling in hot oil before installation.
Spring life seems related to not how MUCH you fly but rather how LITTLE.
 
Springs have ZERO tolerance for rust.

I installed an Impulse Coupling Spring on a Ercoupe Project to address a dead mag.
About a year later the Owner tells me irs acting the same. He had been ground running and taxi ops only. There was a spot of rust where the Spring broke.
Since then I immerse the assembled Coupling in hot oil before installation.
Spring life seems related to not how MUCH you fly but rather how LITTLE.
The Bendix dual mags were dependent on one single impulse spring, and if it broke the power went pretty much to zero, since the timing on both mag sections went to TDC or thereabouts. I thought there was an AD on it but can't find it. Must have been an SB. Any rust pitting of high-carbon spring steel does indeed weaken it tremendously. Cessna now warns of rust pitting on the older flat-leaf main landing gear legs. They have been known to snap at corrosion pits.
 
Bendix/TCM came up with an “improved “ Coupling featuring a much heavier Spring . First Spring I could not install. Fortunately the folks @ Aircraft Magneto Service helped me out.

There is a relatively short TBO period ( 4yrs?) on most Mags. I believe the Spring is a factor in that.
 
The Bendix dual mags were dependent on one single impulse spring, and if it broke the power went pretty much to zero, since the timing on both mag sections went to TDC or thereabouts. I thought there was an AD on it but can't find it. Must have been an SB. Any rust pitting of high-carbon spring steel does indeed weaken it tremendously. Cessna now warns of rust pitting on the older flat-leaf main landing gear legs. They have been known to snap at corrosion pits.
This one? https://rgl.faa.gov/Regulatory_and_...fbdc286e86257020005a1cb9/$FILE/2005-12-06.pdf
 
Perhaps when DRS replaces RGL ( Aug 26th) we may be able to go back to superceded versions of ADs . Till then I’ll hang onto the paper.
 
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