Does this picture show corrosion/pitting in a cylinder?

Good advice. So far I've only hand flown in ifr/imc with my cfi but yes AP can be a double edge sword if you let flying skills deteriorate.

You'll be fine, you sound like you have a solid ability to think and take a well considered position. Practice is the key to safety, just remember you have to practice safety to make it effective though.
 
I'm ex-military so training was a way of life for me during that period and I agree that in flying you have to train so that it's almost automatic reaction to react to problems because the brain tends to freak out when stuff hits the fan. I'm by no means there but that's always been something that I hope to get to w/ my flying.

You'll be fine, you sound like you have a solid ability to think and take a well considered position. Practice is the key to safety, just remember you have to practice safety to make it effective though.
 
No doubt about it, although I advise you do every third approach by hand, and hand fly at least 15-20 minutes of cruise every IFR flight to keep those skills from degrading, because I promise you the A/P will fail you at some point, never get complacent with it.
I disagree, do all your practice approaches by hand, but in real IMC, let the AP do it...you can always disconnect if fails, but if doing it by hand, you can't just engage the AP.
 
I disagree, do all your practice approaches by hand, but in real IMC, let the AP do it...you can always disconnect if fails, but if doing it by hand, you can't just engage the AP.

I disagree for that very reason. It is more difficult to learn the buttonology and complexities to master the automated system than it is to hand fly. Motor skills and hand eye don't degrade as quickly as analytic ability of a complex system. It's easier and more natural for the brain to look at the situation and directly through hand eye coordination control the effects than to analyze a visual situation and figure out how to correct for it indirectly through a servo type function that doesn't provide direct feedback.

If you fly every third approach by hand, given that one flys IFR/IMC reasonably frequently, then motor skills will remain within tolerance. However with advanced avionics there are many obscure details that one continues to learn for a long time, then there is also the 'keep the equipment exercised and function tested' aspect.

There's a lot more to autopilot use with modern A/Ps and avionics than it used to be making it the more complex process now. You can't just hit 'On' anymore, it's a whole process where if you have one wrong setting or initiate something too early or late in the procedure, you end up with a "What is it doing now?" Moment, and those are not good.

Once the hand flying process is learned and mastered, then the avionics/automation process is more complicated and requires the more practice and mental diligence than the hand process.
 
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There's a lot more to autopilot use with modern A/Ps and avionics than it used to be making it the more complex process now. You can't just hit 'On' anymore, it's a whole process where if you have one wrong setting or initiate something too early or late in the procedure, you end up with a "What is it doing now?" Moment, and those are not good.
Which is why you want the AP/GPS/etc all set up from the beginning.
If you need to practice you buttonology you can do that too, anytime, during VFR where if something goes wrong it won't get you in trouble. Same goes for hand flying.
Real IMC is not the time for practicing and it's silly to not use an available tool that can make it safer.
 
Which is why you want the AP/GPS/etc all set up from the beginning.
If you need to practice you buttonology you can do that too, anytime, during VFR where if something goes wrong it won't get you in trouble. Same goes for hand flying.
Real IMC is not the time for practicing and it's silly to not use an available tool that can make it safer.

I agree, which is why you need to know how to use it correctly which means you need to shoot more approaches with it than by hand using it in the clear as well as in IMC. If you make the majority of your flights IFR, the majority of those will have the approach phase in the clear, if you hand fly all of those, your automation skills may fail you on those few approaches you have to fly to minimums.
 
We'll just got word seller is agreeing to all the items in the inspection list (airworthy and non airworthy) so that's great news but now I have to decide how to proceed. He'd rather reduce the price vs. paying a&p to do them.
 
We'll just got word seller is agreeing to all the items in the inspection list (airworthy and non airworthy) so that's great news but now I have to decide how to proceed. He'd rather reduce the price vs. paying a&p to do them.

I agree with him. Get the plane home and have your mechanic do the work so he gets familiar with the plane. If you need, get a ferry permit to get it home.
 
I agree with him. Get the plane home and have your mechanic do the work so he gets familiar with the plane. If you need, get a ferry permit to get it home.
+1
Get it home, now is a good time to established contact with a local mechanic, start making calls, and if you haven't already, finding a hanger, that's too nice of a plane to let sit out on the tarmac.
Plus if you live in a state that charges taxes on airplanes, they will be lower.
 
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My preference would be to bring it home and have repairs done here as I'd rather be involved and start a relationship w/ my local A&P like you guys say. None of the items on the list made the plane un airworthy so no ferry permit needed at all. I already scoped and reserved a hangar at the FBO I got my PPL at and rent out of (which is 10 minutes away from home) plus that's also the shop that will be my A&P. Got insurance lined up too and $ lined up and ready to wire so now I just have to decide if I want to keep the plane in TX and have the seller take the plane to the pre-buy A&P again to pull those 2 cylinders to inspect the cam or bring it home and hope for no surprises. Exciting and SCARY (first airplane so big move)!!!
 
My preference would be to bring it home and have repairs done here as I'd rather be involved and start a relationship w/ my local A&P like you guys say. None of the items on the list made the plane un airworthy so no ferry permit needed at all. I already scoped and reserved a hangar at the FBO I got my PPL at and rent out of (which is 10 minutes away from home) plus that's also the shop that will be my A&P. Got insurance lined up too and $ lined up and ready to wire so now I just have to decide if I want to keep the plane in TX and have the seller take the plane to the pre-buy A&P again to pull those 2 cylinders to inspect the cam or bring it home and hope for no surprises. Exciting and SCARY (first airplane so big move)!!!

What was the date on the overhaul? Has it been flown regularly? What part of TX? If it's been flown regularly 50-100 hrs a year, or is living in a hangar out in Marfa or up north, I wouldn't be all too worried about the cam. If the plane sat for a year in a coastal climate, then I'd check the cam.

The alternative if the guy agrees to it and will assure the cam condition/repair as well, put the cam repair costs into escrow and bring it home so your mechanic can inspect it. If it's good, funds get released to him, if not, you get them for the repair. That's what I would shoot for.
 
Great idea about escrowing... Plane is kept in a REALLY nice airport and hangar near Dallas (I went there for test flight so saw w/ my own eyes). Plane has been flying every month but not very long so last 12 months about 29 hours, year before that 30 some and 40 some the year before and 116 hours the year before that (when owner bought it) and last annual was done in April 2014. Again no warning signs in the oil, filter, compressions and spectrographic oil analysis over the last 3 years (owner has sample sent every year w/ annual and has results of all the tests - all levels are normal).
 
Great idea about escrowing... Plane is kept in a REALLY nice airport and hangar near Dallas (I went there for test flight so saw w/ my own eyes). Plane has been flying every month but not very long so last 12 months about 29 hours, year before that 30 some and 40 some the year before and 116 hours the year before that (when owner bought it) and last annual was done in April 2014. Again no warning signs in the oil, filter, compressions and spectrographic oil analysis over the last 3 years (owner has sample sent every year w/ annual and has results of all the tests - all levels are normal).

Escrow it if he agrees, or even better just hang onto those funds if he agrees, otherwise I'm not particularly fussed over the cam given the oil track record.
 
Yeah broker said he HIGHLY doubts seller would agree to that and he says most sellers would not as they have no way of knowing what I did to engine or who the local A&P is that decides so uphill battle I guess.

I'm getting the plane for $20K below asking price so I'm trying to make a decision based on all these points...

Escrow it if he agrees, or even better just hang onto those funds if he agrees, otherwise I'm not particularly fussed over the cam given the oil track record.
 
Yeah broker said he HIGHLY doubts seller would agree to that and he says most sellers would not as they have no way of knowing what I did to engine or who the local A&P is that decides so uphill battle I guess.

I'm getting the plane for $20K below asking price so I'm trying to make a decision based on all these points...

It never hurts to ask, and pilots are notoriously cheap and he has a top f the market airplane making it difficult to sell, so with a deal this close, he may go for it especially if he believes the cam is good. It appears that both you and he have been handling everything ethically and in good faith so he may agree, heck, maybe you can get him to deliver the plane to you so he knows you didn't abuse it (although there is nothing you can do operationally to abuse a camshaft).

If he balks at the suggestion, I would still go through the deal, you don't find many owners who have done the mods he's done selling their planes because of the loss one takes on those mods at sale so it's not like finding a cheap rag to upgrade which are dime a dozen these days.
 
I'll see what I come up with.

On a different matter.... I have to decide on how to get the plane home. I can either fly to TX w/ my CFI (I need a checkout on a Dakota prior to solo per insurance requirement) or broker said they arrange for ferry pilot and I pay their $250 daily fee plus fuel and airline ticket back home. Thoughts?
 
I'll see what I come up with.

On a different matter.... I have to decide on how to get the plane home. I can either fly to TX w/ my CFI (I need a checkout on a Dakota prior to solo per insurance requirement) or broker said they arrange for ferry pilot and I pay their $250 daily fee plus fuel and airline ticket back home. Thoughts?

Up to you, both will cost about the same, but if you can swing the time for the trip, go with your CFII to go get it, nothing like a nice long cross country to learn the avionics.
 
Yeah that's what I was thinking too. Would be a great trip/experience just harder to arrange but let me see if I can pull it off...
 
This has been an interesting read. It certainly appears to me that the Savvy thing is smoke and mirrors. Their position regarding the cylinders is strange. What's the harm in pulling a cylinder? For them to say their mechanics are the only ones qualified to do it is a big red flag, I would have given them the boot too.

The aircraft appears to be in good condition, and with several years of oil analysis in the logs and good compressions I don't think you should worry about its long term health. The observations by the second A&P in post #72 give me the feeling the aircraft was well cared for. It also sounds like the owner is a reasonable person, as he agreed to a significant price reduction and an allowance for needed repairs.

I hope you enjoy the aircraft. I think doing the ferry flight with an instructor is a good idea, it will allow a few hours of familiarization with the avionics and give you a good jump on learning the systems.

This past Spring I replaced all cylinders on my IO 520, it was done in my hanger and all cylinders were pulled in one afternoon. To minimize the spun bearing potential, each thru bolt got spacers and was retorqued before moving on to the next cylinder.

This is a great idea.
 
Still debating how to proceed but for peace of mind I'm leaning towards having 2 cylinders pulled to ensure there's no corrosion on the cam/lifters. Since seller agreed to having this done I may as well follow through to avoid a surprise later.
 
Still debating how to proceed but for peace of mind I'm leaning towards having 2 cylinders pulled to ensure there's no corrosion on the cam/lifters. Since seller agreed to having this done I may as well follow through to avoid a surprise later.

Maybe I missed something but I thought you said the plane had been flying regularly, every month with at least 30 or so hours a year for the past three years. If that's the case I don't see why you'd be concerned about cam corrosion. For that to occur it would have to sit, completely undisturbed in a generally unfavorable environment for a rather lengthy period of time.

I know the owner has offered it but it seems a shame to fuss with a perfectly happy engine. :dunno:
 
Yes the airplane has been being flown that way over the last 4/5 years and was flown even more before that (prior owner before current one). It's also been in Dallas, TX area so not FL. The reason I'm concerned is because the folks at SAVVY got it in my head that if there's signs of corrosion in the cylinders then the chances are VERY high that there's corrosion in the cam as well PLUS my assumption is that you have to fly a plane weekly (or close to that) to avoid corrosion in the engine so that's why I'm worried about all this and remember... I'm a first time buyer so this is all new for me.

Maybe I missed something but I thought you said the plane had been flying regularly, every month with at least 30 or so hours a year for the past three years. If that's the case I don't see why you'd be concerned about cam corrosion. For that to occur it would have to sit, completely undisturbed in a generally unfavorable environment for a rather lengthy period of time.

I know the owner has offered it but it seems a shame to fuss with a perfectly happy engine. :dunno:
 
Still debating how to proceed but for peace of mind I'm leaning towards having 2 cylinders pulled to ensure there's no corrosion on the cam/lifters. Since seller agreed to having this done I may as well follow through to avoid a surprise later.

Go for it, might as well.
 
Maybe I missed something but I thought you said the plane had been flying regularly, every month with at least 30 or so hours a year for the past three years. If that's the case I don't see why you'd be concerned about cam corrosion. For that to occur it would have to sit, completely undisturbed in a generally unfavorable environment for a rather lengthy period of time.

I know the owner has offered it but it seems a shame to fuss with a perfectly happy engine. :dunno:

I hear ya, to me it's six of one, half a dozen of the other. In the end, it comes down to what brings him peace of mind.
 
Yes the airplane has been being flown that way over the last 4/5 years and was flown even more before that (prior owner before current one). It's also been in Dallas, TX area so not FL. The reason I'm concerned is because the folks at SAVVY got it in my head that if there's signs of corrosion in the cylinders then the chances are VERY high that there's corrosion in the cam as well PLUS my assumption is that you have to fly a plane weekly (or close to that) to avoid corrosion in the engine so that's why I'm worried about all this and remember... I'm a first time buyer so this is all new for me.

No no no, not weekly, and if you use Cam Guard it also provides a better adhering barrier film. When I store an engine for more than a couple of months I'll pour in a bottle or two (depending on total capacity, I try for 4:1 with good oil and Cam Guard) of Lucas Oil Treatment because it provides a serious adhesive film. I'll start the engine as lean as possible, run it up a bit to get the oil splashed around real good and shut her down. When I bring the engine out of storage I'll run it up until warm to get any dried, oxidized film rinsed back off the surface and change the oil.

I'll give you the benefit of what Ed Collins, maker of Cam Guard and former petrochemical engineer for Exxon who was tasked and funded by them to develop the best Aviation oil (then rejected it as not cost effective and just copied Aeroshell 20-50s Semi Synth oil which is junk) possible gave me.

His recommendation is to use any of the straight weight oils, or if you want a multi viscosity oil to only use Phillips XC 20-50 (what I use) and dose it with Cam Guard. Ed is available through this board, and if you ever want to talk with him, he has a wealth of knowledge that he will freely share. In fact, he called me one day over a thread because 'It's easier to explain it on the phone', that call lasted 2 hours and was extremely interesting, I wish I would have recorded it for a Podcast because I think everyone should have the base that he so generously gave me. Yes, he is selling a product, but it's a good product with millions of dollars of scientific research and testing behind it.
 
I was under the impression that cylinder and cam corrosion can happen in a matter of weeks on inactivity. That's what I was told when I asked because I found it strange that a plane that was hangared in Dallas and getting flown at least 30+ hours a year and with no problems with oil analysis could show corrosion in the cylinders through a borescope. Not only that but owner uses aero shell 100w plus which I've learned is thicker than multi weights and so gives better rust preotection. I was told corrosion can start very quickly.

I will be using cam guard after reading about it. Wish currents owner had done so as well.

No no no, not weekly, and if you use Cam Guard it also provides a better adhering barrier film. When I store an engine for more than a couple of months I'll pour in a bottle or two (depending on total capacity, I try for 4:1 with good oil and Cam Guard) of Lucas Oil Treatment because it provides a serious adhesive film. I'll start the engine as lean as possible, run it up a bit to get the oil splashed around real good and shut her down. When I bring the engine out of storage I'll run it up until warm to get any dried, oxidized film rinsed back off the surface and change the oil.

I'll give you the benefit of what Ed Collins, maker of Cam Guard and former petrochemical engineer for Exxon who was tasked and funded by them to develop the best Aviation oil (then rejected it as not cost effective and just copied Aeroshell 20-50s Semi Synth oil which is junk) possible gave me.

His recommendation is to use any of the straight weight oils, or if you want a multi viscosity oil to only use Phillips XC 20-50 (what I use) and dose it with Cam Guard. Ed is available through this board, and if you ever want to talk with him, he has a wealth of knowledge that he will freely share. In fact, he called me one day over a thread because 'It's easier to explain it on the phone', that call lasted 2 hours and was extremely interesting, I wish I would have recorded it for a Podcast because I think everyone should have the base that he so generously gave me. Yes, he is selling a product, but it's a good product with millions of dollars of scientific research and testing behind it.
 
I was under the impression that cylinder and cam corrosion can happen in a matter of weeks on inactivity. That's what I was told when I asked because I found it strange that a plane that was hangared in Dallas and getting flown at least 30+ hours a year and with no problems with oil analysis could show corrosion in the cylinders through a borescope. Not only that but owner uses aero shell 100w plus which I've learned is thicker than multi weights and so gives better rust preotection. I was told corrosion can start very quickly.



I will be using cam guard after reading about it. Wish currents owner had done so as well.


And the corrosion myth continues...go to the coast, walk the docks of the marinas, every boat you see has engines exposed to salt air, high humidity, and sit for months.
 
I was under the impression that cylinder and cam corrosion can happen in a matter of weeks on inactivity. That's what I was told when I asked because I found it strange that a plane that was hangared in Dallas and getting flown at least 30+ hours a year and with no problems with oil analysis could show corrosion in the cylinders through a borescope. Not only that but owner uses aero shell 100w plus which I've learned is thicker than multi weights and so gives better rust preotection. I was told corrosion can start very quickly.

I will be using cam guard after reading about it. Wish currents owner had done so as well.

Cylinders live in a different environment than the cam, the part you can see the rings scrape the oil off and the residual heat on shut down bakes out the thin thin thin film they leave behind.
 
Ok thanks guys!

Cylinders live in a different environment than the cam, the part you can see the rings scrape the oil off and the residual heat on shut down bakes out the thin thin thin film they leave behind.
 
The amount of boats out there running on engines that had been rusted seized and then revived without disassembly and continue to run for years would likely astound you.

When i got my Catalina 30, the owner told me the engine was seized. i spent a couple weekends working on it, put a large socket on the pulley on the crank, held open the compression release, and it was able to turn. replaced the battery and ignition switch, and had a running motor. Should have changed the oil and filter first because as soon as the oil pressure came up, the filter blew out and filled the bilge with 4 qt of oil that took the better part of 6 months to get all the oil film cleaned up
 
This airplane sat for 19 years. It had a seized engine. A&P oil soaked the cylinders and got her to break loose. This engine was not taken apart just serviced.

It has been flown to Oshkosh now and many other places. It does have chrome cylinder. Had a complete engine rebuild, flown about 150 hrs then parked for 19 years and not touched.

When I saw this airplane the first time, I thought it needed to be junked. Tells you what I know...Not Crap...

https://www.youtube.com/watch?v=GKquyLtWhL8

Tony
 
Wonder why then there is so much concern about corrosion/pitting of cylinders/cams/lifters to the point that SAVVY (and Mike Busch himself) told me to walk away from this plane unless seller was willing to discount the price by the cost to overhaul it as in their opinion corrosion in the cylinder makes it a high risk engine.
 
Guys I'm not trying to create an argument here I'm just researching/verifying what I was told by SAVVY because it didn't sound right to me.

My local A&P finally had time to look at the oil analysis & borescope picture supplied by the SAVVY A&P and he echoes the comments I've been getting here and from others I've been asking. Basically he said for starters that borescope image is VERY poor quality to begin with, at best he sees what appears to be normal corrosion (the type that wears w/ use) and given that compressions were good and results of last 3 spektographic oil analysis he sees no problems as all measurements are normal and oil sample and filter showed no signs of metals, carbon, and oil was clear. He said if seller is still willing to have 1 cylinder pulled that would be the only way to really tell and if he's willing to do that then I should take him up on it. He did say that no more than 2 cylinders should be taken out at a time.

So like I said at this stage I've lost trust & confidence in SAVVY so I'm working on getting a second opinion by paying for another pre-buy from a different A&P. Too many inconsistencies in what SAVVY has said to me for me to continue to trust me. They've flipped flopped their arguments too many times.

This thread took a turn as they often do around here.

I will provide some examples from the pre-buy inspection of my a/c for reference, although it is probably moot at this point in the life of this thread.

Examples of cam spalling, reciprocation wear (from bearing) on the cylinder wall, cylinder pitting from corrosion. In one of the pics the mechanic actually thought it looked like three distinct levels of corrosion as if the piston had been in one position for a *very* long time.

To finish the story, I didn't buy the airplane until the seller (to his great credit) agreed to have the engine torn down by a reputable engine shop and repaired, which cost more than $20k. All of the damage to this engine happened while sitting in coastal Oregon, on the previous owner's watch (IOW, 2 owners before me). This is why I recommend borescoping an engine during pre-buy.
 

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Great images so Thanks. If you don't mind what ended up being replaced/repaired to get it to the $20K mark? Also did the seller handle the repairs before you eventually bought it or did he reduce the price by $20K (estimate to inspect/repair) and then you had the work done?

This thread took a turn as they often do around here.

I will provide some examples from the pre-buy inspection of my a/c for reference, although it is probably moot at this point in the life of this thread.

Examples of cam spalling, reciprocation wear (from bearing) on the cylinder wall, cylinder pitting from corrosion. In one of the pics the mechanic actually thought it looked like three distinct levels of corrosion as if the piston had been in one position for a *very* long time.

To finish the story, I didn't buy the airplane until the seller (to his great credit) agreed to have the engine torn down by a reputable engine shop and repaired, which cost more than $20k. All of the damage to this engine happened while sitting in coastal Oregon, on the previous owner's watch (IOW, 2 owners before me). This is why I recommend borescoping an engine during pre-buy.
 
The $20k was the bill from his mechanic for removing, crating, shipping, Western Skyways repair, and reinstalling the engine.

Western Skyways tore the engine down and inspected all components, including the crankshaft, and ended up replacing all pistons, new oil pump, new cam, new vac pump, and they honed all the cylinders to P10 (0.01" over bore IIRC). Skyways sent me their actual measurement sheet which I was told they almost never do. I just wanted to make sure I had some record of what they did. I don't have that available right now. I also saw a copy of seller's mechanic's bill at some point.

We (me, via my broker) requested that the seller actually accomplish the repair before purchase because we didn't know what else they might find wrong with an engine that had obviously sat a long time. Seller first asked if his home field shop could do the repair. My broker and I agreed that they might be OK doing a cylinder swap but we didn't want him cracking the case. Seller agreed to have a reputable engine shop so the repair.

I can't say enough good things about the seller. He flew down to KAPA from ID and had us not only reject the airplane but also tell them their engine has maybe 50 to 75 left on it. But my broker was very professional and added a level of credibility to all the discussions that I certainly couldn't match. The broker and the mechanic (who did my pre-buy) both worked for the same shop - Arapahoe Aero at KAPA.
 
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Sounds like you got a great pre-buy and great seller.
 
I just got some new borescope pictures and these look a lot worse than I would have expected. Any opinions on these?
 

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Netsurfer, are those photos of cylinder walls, and are the first two photos essentially the same thing?
 
Yes those are cylinder wall and I think a bit of the piston head? And yes the first 2 are the same area in the same cylinder.
 
Wonder why then there is so much concern about corrosion/pitting of cylinders/cams/lifters to the point that SAVVY (and Mike Busch himself) told me to walk away from this plane unless seller was willing to discount the price by the cost to overhaul it as in their opinion corrosion in the cylinder makes it a high risk engine.

I've been trying to work out the histrionics on that as well, kind of confusing really. The sad thing is the only thing I can work out is it's fear mongering to get his associated A&P work which he gets a cut of.:dunno:
 
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