Low time engine.

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cap41
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Low time engine.

Post by cap41 »

Looking at an airplane with 0-320 in it. 1400 hours. TOP-OH in 09. since than less than 100 hours. usually 10-15 hours per year. Presently the airplane has not flown in 6 months. last 2 years its been in Halifax, before than it was central ontario.

Can someone point out the issues in concerns. Corrosion etc. Would a preemptive Top OH help? or is the issue going to be with the bottom end? We would have a PPI done. but any corrosion might be scrubbed off with first start.
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ahramin
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Re: Low time engine.

Post by ahramin »

Cam probably needs to be replaced. A preemptive top overhaul is a spectacularly bad idea. Cylinders are accessories, and are most likely to fail in the first 100 hours.

You need a PPI done by someone up to date on the latest maintenance philosophy and should include a boroscope inspection of the cylinders and oil analysis to try to get an idea of how much metal the engine is making. No way to be certain about the crank and cam without opening up the engine though.

Easy answer, unless you are getting a price on this aircraft that values the engine at $0, walk away now. No point going any further.
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cgzro
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Re: Low time engine.

Post by cgzro »

agreed, the camshaft and lifters are probably rusted and will start to fail as a result. This requires the case to be split to repair which essentially means an overhaul. Value the plane assuming it will need an overhaul shortly.
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cap41
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Re: Low time engine.

Post by cap41 »

Can a borescope have a view at cam and lifters?

Will a clean oil analysis be of value?
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photofly
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Re: Low time engine.

Post by photofly »

No, and no.

You can have a look at the camshaft if you pull one of the cylinders. But if it was my aircraft for sale and you told me you wanted to do that pre-purchase, I'd tell you to take a hike.
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cap41
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Re: Low time engine.

Post by cap41 »

photofly wrote:No, and no.

You can have a look at the camshaft if you pull one of the cylinders. But if it was my aircraft for sale and you told me you wanted to do that pre-purchase, I'd tell you to take a hike.
What is the time/labour to pull a cylinder and re install? Will pulling one cylinder be enough?

What is your suggestion for piece of mind?

Also, with TOP OH 6 years old, and approx 60-70 hours. If we decided to buy and do a complete OH, Can the cylinders be reused? allowing us in theory just to do the bottom end?
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Pavese
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Re: Low time engine.

Post by Pavese »

Cap, check PMs.

D 8)
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photofly
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Re: Low time engine.

Post by photofly »

>>What is your suggestion for piece of mind?

You're buying a used airplane. You can't have peace of mind. Things will break and land you with $10k repairs when you least expect it - man up and enjoy the uncertainty of not knowing what bills tomorrow will bring. If you can't do that then stick to renting.

My advice if you like the plane is make a low-ish offer based on poor engine usage, buy the thing, and have fun flying it. If someone else offers more and it goes to them instead, they wanted it more than you did - so good luck to them.

>>We would have a PPI done...

There's a lot more to look at than just the engine.
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DId you hear the one about the jurisprudence fetishist? He got off on a technicality.
cap41
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Re: Low time engine.

Post by cap41 »

This site used to be full of insightful thought out answers. I ask questions in the maint section because that were I assumed the professionals/AME/AMO would respond. I can man up a pay for a 10K repair thats not the issue or the question. I know nothing about the subject at hand. Therefore I ask a question. I am well aware of regular maint etc on an airplane. I was unsure what to look for, and the hazards of buying this type of engine. Asides from run from this deal etc, or man up, I thought some people would share similar experiences. This site has gone down hill fast. The lack of civility is overwhelming sometimes.

What ever happened to people helping people. Now its just public shaming because someone knows more than another....................Flame away :)
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DonutHole
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Re: Low time engine.

Post by DonutHole »

cap41 wrote:Looking at an airplane with 0-320 in it. 1400 hours. TOP-OH in 09. since than less than 100 hours. usually 10-15 hours per year. Presently the airplane has not flown in 6 months. last 2 years its been in Halifax, before than it was central ontario.

Can someone point out the issues in concerns. Corrosion etc. Would a preemptive Top OH help? or is the issue going to be with the bottom end? We would have a PPI done. but any corrosion might be scrubbed off with first start.
so it flew a life with 15 - 20 hours a year with no major issues.

it has sat for six months, but since the top overhaul its pretty much been flown the average it has experienced over its life. So, going purely with the numbers, and lack of issues, that plane seems to be happy flying fifteen hours a year.

Make the sale contingent upon annual, with 20 hours flight time and an oil analysis. I doubt, given the use history of that airplane, that it is sitting there as junk. Why would it be? They've done nothing different than they have over the course of that aircrafts life and it has never had a problem in the past. The trend is, that with those hours flown on that engine it doesn't make metal or have issues (other than the toh)

it doesn't sound particularly neglected to me. six months can cause issues, but i've seen worse sit for longer and still be serviceable.

The only way to be sure is to look at the cam, that is most likely where the most expensive problems will occur.

obviously you know that an aircraft is more than an engine and some seats. 172s are not mysterious and they hold few secrets. Even a laypersons look over will catch most serious issues, I mean, I can teach a ten year old what a crack in aluminum looks like.

I would pay particular attention to the interior of the wings, particularly at the back edge. It sat in a salt air environment and corrosion can develop quickly. If you do have an annual done, I recommend having the inside of the wings fogged with acf-50 as preventative maintenance. Other than that make sure all applicable ad's are up to date and you should have a good chance of having a solid aircraft.

good luck
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cap41
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Re: Low time engine.

Post by cap41 »

Thank you very much. those are the type of responses i was looking for.
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cgzro
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Re: Low time engine.

Post by cgzro »

Seems you have three responses.

1 - camshaft will be shot and engine won't last (from aircraft owner who's had this problem)
2 - camshaft will be shot and engine won't last (from aircraft owner, don't know if he's had this problem)
3 - engine probably ok and some good advice on airframe.

Here are a few other things to consider. What does the engine manufacturer say about preserving the engine when its sitting idle, and how long do they consider an idle period to be? What has the engine manufacturer recently done to help minimize this problem? The answer to these two questions should lend a bit more weight to 1) and 2) above and will be delivered in the cold hard manner of a google search rather than grumpy aircraft owners that fork out 10's of thousands a year to keep these things running ;)

Anyway don't shoot the messenger .. just do your own homework.
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photofly
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Re: Low time engine.

Post by photofly »

>>Make the sale contingent upon annual, with 20 hours flight time and an oil analysis

Even the most idiotic owner isn't going to contemplate a sale contingent on any such thing.
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DId you hear the one about the jurisprudence fetishist? He got off on a technicality.
DonutHole
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Re: Low time engine.

Post by DonutHole »

photofly wrote:>>Make the sale contingent upon annual, with 20 hours flight time and an oil analysis

Even the most idiotic owner isn't going to contemplate a sale contingent on any such thing.
I've seen it done twice. Once the idiotic owner realizes it's the only way to get his perceived value back out of the airframe they come around.
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PilotDAR
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Re: Low time engine.

Post by PilotDAR »

What is your suggestion for piece of mind?
Cap, My suggestion for peace of mind is to relax, and accept some risk - within your personal financial capacity. In this case, that risk will be the possible re & re of the engine, and overhaul or repair. If you had to, could you afford it? The topic of cost has been rather beaten to death poorly here lately, so there are some numbers, and sources of information. Budget the high end values you have seen written, and perhaps it will be less. Perhaps you won't need to at all. Perhaps you get a few hundred hours of trouble free hours flying before it needs work. Sometimes, for the reward [the freedom to fly], you gotta take the risk. When I have, it's always been worth it in the long run.

Last year, I bought a damaged aircraft overseas, based only on some external photos, and spent that value again to get it home. I'm repairing it, and happy with my decision. I took a risk within my financial capacity, and it's okay.

A fellow bought a plane months ago, following a few hours fam flight in it. He spent tens of thousands to return it to being airworthy, which was not really in the plan, but it had to be done. It's now a +$100k plane. Hull insurance premium was beyond his tolerance, so he purchased liability insurance only. He accepts that risk. Today I flew it's maintenance check flight, and thereafter 1.7 hours of training in it for him. If he gets it wrong, and I don't make it right, he's out the plane - He accepts the risk.

Cap, it is very wise the PPI the aircraft. That said, the practicality of ascertaining the actual condition of the internal engine with an external PPI is poor - you could do an internal engine PPI, but its very costly. You can mitigate some risk and cost, but not all. For my experience, there is the remaining risk that even if you inspected the engine internally, and satisfied yourself that there was no defect, something else could still go wrong, and you still have repair cost - it happens....

Asking here is wise in your due diligence. Many posters seem to have your better interests at heart. But at the end of the day, you cannot eliminate risk, you can only address it, and prepare for it.
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photofly
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Re: Low time engine.

Post by photofly »

DonutHole wrote:
photofly wrote:>>Make the sale contingent upon annual, with 20 hours flight time and an oil analysis

Even the most idiotic owner isn't going to contemplate a sale contingent on any such thing.
I've seen it done twice. Once the idiotic owner realizes it's the only way to get his perceived value back out of the airframe they come around.
There's the rub. Comparing the owner's perceived value of an old 172 with a tired engine, with what it will fetch, is an interesting exercise.
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DId you hear the one about the jurisprudence fetishist? He got off on a technicality.
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Strega
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Re: Low time engine.

Post by Strega »

TBH.. the engine on this 172 is prolly done.. that being said,, ,if you run it the way it is,, you will probably have a couple years of flying (@50 hrs/year)...

My recommendation is to take advice from other aircraft owners that have been doing this for a while...
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culver10
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Re: Low time engine.

Post by culver10 »

One of the wonderful things about Lycoming engines is that they rarely have a catastrophic failure that will turn you into a glider. I had a Supercub fly in here many years ago for a restoration and the cam was so worn down from corrosion that the valves would barely open! It still flew in. It turned out the crank was cracked and most of engine was toast, but it still flew. So if you want “piece of mind”, buying a 4 cylinder Lycoming is part of it. So if you buy this plane and it has corrosion on the cam and lifters, it will eventually show itself in oil analysis or maybe even by examining the oil filter internals. You can do a corrosion repair to the bottom end instead of a complete overhaul, and then keep flying.
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Last edited by culver10 on Thu Nov 05, 2015 5:51 pm, edited 1 time in total.
Sulako
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Re: Low time engine.

Post by Sulako »

Let's get back on topic, shall we?

And also, it's not nice to throw shade at other people's professions. Please be nice.
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blackhands4
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Re: Low time engine.

Post by blackhands4 »

cap41 wrote:This site used to be full of insightful thought out answers. I ask questions in the maint section because that were I assumed the professionals/AME/AMO would respond. I can man up a pay for a 10K repair thats not the issue or the question. I know nothing about the subject at hand. Therefore I ask a question. I am well aware of regular maint etc on an airplane. I was unsure what to look for, and the hazards of buying this type of engine. Asides from run from this deal etc, or man up, I thought some people would share similar experiences. This site has gone down hill fast. The lack of civility is overwhelming sometimes.

What ever happened to people helping people. Now its just public shaming because someone knows more than another....................Flame away :)



I hear yeah! You see it all over. Its pretty disgusting to be honest!
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