Prepurchase inspection on a M20j what to look for

[Shiroyuki]

Hi everyone

I'm looking to purchase a 1981 M20J with some recently upgraded avionics and an engine near tbo. The price of the airplane is reasonable but at the top of my budget.

The engine currently sits at 1850 smoh. it had flown roughly 200 hours in the past 3 years, and about about 30 hour a year before that all the way back to 2008 where the plane is imported into Canada. The seller says the engine is running great.

My mechanic and I both think we want to know how's the interal situation of the engine and we want to two cylinders pulled and have a look. The plane is fresh out of an annual with 0 hour so we can inspect the filter element and do an oil analysis. The seller claims he has an oil sample preserved from last annual and will allow us to send it out which I'm not very confident it would help. He also doesn't want to have the cylinder pulled, even though I'm paying the cost and we will split 50/50 if anything is found unairworthy after the cylinder is pulled, for example if it need a new camshaft.

I know it is a very invasive procedure and can introduce some risk when the engine is put back together. But I'm also not exactly interested in buying a plane that's falling apart inside.

I would love to hear you opinion on if I should insists on having the cylinders pulled, or would you be happy with an oil analysis with no previous baseline value?

Also, is there other thing I need to check for? Like fuel tank leak etc?

Thanks

[mike_elliott]

Regarding pulling a cylinder.

You are willing to purchase a plane with an at or near tbo engine. You already know there will be wear on the tappets and cam lobes and you already know you will be replacing and overhauling soon. You already have a discounted sales price for this I assume.

If I were the owner I would not agree to this after fully disclosing all known engine conditions anyway. All kinds of new issues could be introduced for no reasons not previou$ly mitigated by price

You need to focus on the quality of the airframe and corrosion condition. If acceptable go for it knowing your going to have to spend the big bucks on the engine soon.

If the tanks haven't been resealed in 20 years, they will need it coming up. That sealant, like bladders, don't last forever

Have someone who knows how to pre purchase inspect a Mooney do a proper pre buy, you will get your value there.

The Internet opinions are for us old armchair quarterbacks to enjoy reading

[Shadrach]

My opinion is that it is unreasonable to ask for an invasive inspection when an aircraft is in service with a reasonable useage history. Especially in the case of an engine at 1850hrs. It should be priced as run out. If it runs longer (and it likely will), great. The only time I think it is reasonably to ask for a cylinder removal is under very special circumstances where both parties are very engaged but have reached an impasse. For instance a low time engine that is not in service and has not been for an extended period. Even in that situation it’s reasonable for the seller to refuse. It also reasonable for the buyer to pass. 

[Danb]

Well the two previous statements beat me to the show, your already purchasing a plane on condition that the engine is on borrowed time I’d consider all the hours you fly is a bonus, consider ordering or getting on the list for an Engine o/h or purchase. I’d get a quality pre purchase inspection by a Mooney mechanic who knows where to look for corrosion and other Mooney specific issues. If the plane meets this buy and be ready for the exchange. You mentioned good avionics which are big dollars I think your ahead of the game especially if you can get 2-300 hours of free flying 

D

[EricJ]

+1 on the above.   If I was selling I wouldn't allow that, especially on a high-ish time engine.   I'll also suggest that if the purchase price is near your limit, if you don't have sufficient resources to do an overhaul or major work soon, you'll probably want to find something else.   

[LANCECASPER]

8 hours ago, Shiroyuki said:

Hi everyone

I'm looking to purchase a 1981 M20J with some recently upgraded avionics and an engine near tbo. The price of the airplane is reasonable but at the top of my budget.

The engine currently sits at 1850 smoh. it had flown roughly 200 hours in the past 3 years, and about about 30 hour a year before that all the way back to 2008 where the plane is imported into Canada. The seller says the engine is running great.

My mechanic and I both think we want to know how's the interal situation of the engine and we want to two cylinders pulled and have a look. The plane is fresh out of an annual with 0 hour so we can inspect the filter element and do an oil analysis. The seller claims he has an oil sample preserved from last annual and will allow us to send it out which I'm not very confident it would help. He also doesn't want to have the cylinder pulled, even though I'm paying the cost and we will split 50/50 if anything is found unairworthy after the cylinder is pulled, for example if it need a new camshaft.

I know it is a very invasive procedure and can introduce some risk when the engine is put back together. But I'm also not exactly interested in buying a plane that's falling apart inside.

I would love to hear you opinion on if I should insists on having the cylinders pulled, or would you be happy with an oil analysis with no previous baseline value?

Also, is there other thing I need to check for? Like fuel tank leak etc?

Thanks

As has been mentioned, you would have to question the sanity of any Seller if he allowed you to pull two cylinders in a pre-buy on an airplane priced with a run-out engine. 

You mentioned that the price of the airplane is at the top of your budget. This is going to sound direct - please don't take offense: Provided that the airplane does pass a pre-buy evaluation, do you?

Knowing that the engine is near TBO (yes it could go longer) do you have the funds in place if the engine starts making metal soon after purchase? Could you place an order for a factory reman and not be financially strapped?  The reason I ask those questions is that this same thing has happened to people on here - they've bought a "great deal" and then soon after they find a major expense that can't be covered. Worst yet they finance a "great deal" and then are making payments on an airplane that can't be flown. The initial price of an airplane is relatively low compared to what it will cost to maintain it, fly it, upgrade it and insure it over the years.

It's one thing to run an engine past TBO if you were the one who put the last few hundred hours on it, but I'd be less anxious to plan on doing it in this case.

[N201MKTurbo]

I wouldn’t take apart an engine with 1850 hours on it that was running well. There is nothing to be gained. Your concern with the cam is unfounded. The cam in a runout engine has little value unless you are expecting to regrind it. The value in a runout engine is in the crank, case and gears. Everything else gets replaced. Pulling two cylinders will not let you inspect anything of value.

My suggestion with a high time engine is to just keep an eye on the filter and screens and if it stares to make metal, pull the trigger and get it overhauled. Otherwise, enjoy the engine until its performance suffers or its oil consumption gets to be a PITA.

[toto]

8 hours ago, Shiroyuki said:

Hi everyone

I'm looking to purchase a 1981 M20J with some recently upgraded avionics and an engine near tbo. The price of the airplane is reasonable but at the top of my budget.

The engine currently sits at 1850 smoh. it had flown roughly 200 hours in the past 3 years, and about about 30 hour a year before that all the way back to 2008 where the plane is imported into Canada. The seller says the engine is running great.

My mechanic and I both think we want to know how's the interal situation of the engine and we want to two cylinders pulled and have a look. The plane is fresh out of an annual with 0 hour so we can inspect the filter element and do an oil analysis. The seller claims he has an oil sample preserved from last annual and will allow us to send it out which I'm not very confident it would help. He also doesn't want to have the cylinder pulled, even though I'm paying the cost and we will split 50/50 if anything is found unairworthy after the cylinder is pulled, for example if it need a new camshaft.

I know it is a very invasive procedure and can introduce some risk when the engine is put back together. But I'm also not exactly interested in buying a plane that's falling apart inside.

I would love to hear you opinion on if I should insists on having the cylinders pulled, or would you be happy with an oil analysis with no previous baseline value?

Also, is there other thing I need to check for? Like fuel tank leak etc?

Thanks

https://web.archive.org/web/20190207032803/http://donmaxwell.com/pre-purchase-inspections/

[Fritz1]

Need reserves for the endeavor, bullet proof wind forecast still does not allow flight without fuel reserves, you are safe on the ground right now, keep your powder dry to be able to fly another day, it is better to have money wishing to have an airplane than the other way around

[Shiroyuki]

54 minutes ago, LANCECASPER said:

As has been mentioned, you would have to question the sanity of any Seller if he allowed you to pull two cylinders in a pre-buy on an airplane priced with a run-out engine. 

You mentioned that the price of the airplane is at the top of your budget. This is going to sound direct - please don't take offense: Provided that the airplane does pass a pre-buy evaluation, do you?

Knowing that the engine is near TBO (yes it could go longer) do you have the funds in place if the engine starts making metal soon after purchase? Could you place an order for a factory reman and not be financially strapped?  The reason I ask those questions is that this same thing has happened to people on here - they've bought a "great deal" and then soon after they find a major expense that can't be covered. Worst yet they finance a "great deal" and then are making payments on an airplane that can't be flown. The initial price of an airplane is relatively low compared to what it will cost to maintain it, fly it, upgrade it and insure it over the years.

It's one thing to run an engine past TBO if you were the one who put the last few hundred hours on it, but I'd be less anxious to plan on doing it in this case.

Regarding the overhaul, yes it is at the top of my budget, and I’m aware that it might need an overhaul any day now. 

I do have extra cash in hand just enough for a fresh overhaul, I wouldn’t even consider purchasing this airplane if I don’t have the money to overhaul it. But if i have the engine overhaul today that would leave me no other money for other repairs if something else go wrong, like if i have to reseal the tanks. If the engine could run for another two year I would be more comfortable with doing the overhaul. By the time it’s likely that i would also got an upgrade to left seat at my company.

i did check the books and it says tanks for resealed on 2005. Corrosion shouldn’t be an issue since the plane is hangared all its life. My mechanic seems to know what he’s doing and he has my trust on inspecting those.

My first option actually isn’t this airplane. I was looking at another M20J with ok-ish avionics, gns430, some old nav/com, good enough for getting through some bad weather but not hard IFR, which I would not do even in this Mooney. That plane has a 0 time engine and is $30,000 cheaper. The only problem is the owner does not allow my mechanic to inspect the plane and insisted on having a local mechanic from his airport to do the pre purchase inspection. I figured that sounds fishy, and he lied to me about damage history as well which i figured out soon when reviewing the logbooks.

I’ve got a pretty descent idea of my routine cost. My insurance quoted me 2500$ for full in motion and not in motion coverage. My local airport’s parking is roughly 2000$ a year. I would love to get a hangar but my local airport does not have any T hangars. It’s a remote airport in the Canadian north where highway ends.

Since i live in an area where it is extremely geographically remote, deep in Canadian Shield, the purpose of the inspection is less about making sure the plane will last another 500 hours, but make sure there’s nothing that’s going to fail catastrophically soon. A forced landing here is going to be fun, it’s either frozen lake or rocky terrain with forest cover. 

[Shiroyuki]

1 hour ago, N201MKTurbo said:

I wouldn’t take apart an engine with 1850 hours on it that was running well. There is nothing to be gained. Your concern with the cam is unfounded. The cam in a runout engine has little value unless you are expecting to regrind it. The value in a runout engine is in the crank, case and gears. Everything else gets replaced. Pulling two cylinders will not let you inspect anything of value.

My suggestion with a high time engine is to just keep an eye on the filter and screens and if it stares to make metal, pull the trigger and get it overhauled. Otherwise, enjoy the engine until its performance suffers or its oil consumption gets to be a PITA.

I don’t think this engine has an established history of oil and filter analysis. I would not hesitate to make the purchase if they do. They don’t even have any time since last oil change so I can’t even inspect the filter and send out and oil sample.

they do claim they preserved an sample from annual which is literally last week. The seller says he will find if his mechanic sent it out or still have it at his hangar.

my question is, if i start doing oil analysis now, is it too late to establish a baseline?

[Fly Boomer]

9 hours ago, Shiroyuki said:

I would love to hear you opinion on if I should insists on having the cylinders pulled

Corrosion trumps everything.  Only a Mooney expert knows where to look.

Read this:

https://mooneyspace.com/topic/41820-will-it-ever-fly-again-shall-i-dare-rescuing-the-abandoned-bird/

[N201MKTurbo]

25 minutes ago, Shiroyuki said:

I don’t think this engine has an established history of oil and filter analysis. I would not hesitate to make the purchase if they do. They don’t even have any time since last oil change so I can’t even inspect the filter and send out and oil sample.

they do claim they preserved an sample from annual which is literally last week. The seller says he will find if his mechanic sent it out or still have it at his hangar.

my question is, if i start doing oil analysis now, is it too late to establish a baseline?

You can do oil analysis, but just checking the screens and filter should be good enough.

What info are you expecting from oil analysis that you won’t get from inspecting the screens and filter? If it was a low time engine, I supposed it could let you know that something needed repair, but there are no repairs with this engine. You are going to run it till it needs overhaul.

[Fritz1]

Yes, airframe corrosion the one and only show stopper, instead of surmising about engine condition I would fly the airplane for 5h and cut the filter, if good buy the airplane, if not pay the owner an agreed upon amount that you have put in escrow as a gesture of good faith, put yourself in the shoes of the owner

[mike_elliott]

14 minutes ago, N201MKTurbo said:

You can do oil analysis, but just checking the screens and filter should be good enough.

What info are you expecting from oil analysis that you won’t get from inspecting the screens and filter? If it was a low time engine, I supposed it could let you know that something needed repair, but there are no repairs with this engine. You are going to run it till it needs overhaul.

Agree with Rich, just have your mx yank the suction screen if he's up to the task and check if any part numbers are found on metal shavings if present. A failing tappet will leave parts of itself there Everytime. 

[Shadrach]

57 minutes ago, Shiroyuki said:

Regarding the overhaul, yes it is at the top of my budget, and I’m aware that it might need an overhaul any day now. 

I do have extra cash in hand just enough for a fresh overhaul, I wouldn’t even consider purchasing this airplane if I don’t have the money to overhaul it. But if i have the engine overhaul today that would leave me no other money for other repairs if something else go wrong, like if i have to reseal the tanks. If the engine could run for another two year I would be more comfortable with doing the overhaul. By the time it’s likely that i would also got an upgrade to left seat at my company.

i did check the books and it says tanks for resealed on 2005. Corrosion shouldn’t be an issue since the plane is hangared all its life. My mechanic seems to know what he’s doing and he has my trust on inspecting those.

My first option actually isn’t this airplane. I was looking at another M20J with ok-ish avionics, gns430, some old nav/com, good enough for getting through some bad weather but not hard IFR, which I would not do even in this Mooney. That plane has a 0 time engine and is $30,000 cheaper. The only problem is the owner does not allow my mechanic to inspect the plane and insisted on having a local mechanic from his airport to do the pre purchase inspection. I figured that sounds fishy, and he lied to me about damage history as well which i figured out soon when reviewing the logbooks.

I’ve got a pretty descent idea of my routine cost. My insurance quoted me 2500$ for full in motion and not in motion coverage. My local airport’s parking is roughly 2000$ a year. I would love to get a hangar but my local airport does not have any T hangars. It’s a remote airport in the Canadian north where highway ends.

Since i live in an area where it is extremely geographically remote, deep in Canadian Shield, the purpose of the inspection is less about making sure the plane will last another 500 hours, but make sure there’s nothing that’s going to fail catastrophically soon. A forced landing here is going to be fun, it’s either frozen lake or rocky terrain with forest cover. 

Nothing a cylinder removal shows is likely to fail catastrophically. Spalled cams degrade performance, they don’t end an engine’s life without giving significant warning. There are no guarantees that an engine won’t fail. A tell tale sign is how it runs. Does it provide smooth operation with good performance within desirable temp ranges?  It has fresh oil in the sump. Measure the level and note the color. Then go test fly it for a few hours and note the changes. There is only so much that can be done to verify. However, most engines that run really well with good temps are not just waiting for a new buyer to self destruct. They typically soldier on. 

[N201MKTurbo]

The things that make an engine quit in flight are generally fuel and spark related. not the hard metal parts. when the hard metal parts fail it is generally oil related, not wear related. As long as there is oil in the sump and fuel in the tanks and the mags keep making spark, the engine has a very high likelihood of taking you where you want to go.

[MikeOH]

More of the same:

1) Unreasonable request to pull cylinders

2) Make sure the price accounts for a run-out engine

3) Make sure you can afford an OH

4) Base your purchase decision on everything else.

 

Six years ago I was in a similar situation when I bought my F; 2100 SMOH.  I was more comfortable with the fact the plane had been consistently flown around 100 hours a year for the last 13 years than anything else.  I could afford an OH so I went ahead with the purchase. No regrets.

[Ragsf15e]

2 minutes ago, MikeOH said:

More of the same:

1) Unreasonable request to pull cylinders

2) Make sure the price accounts for a run-out engine

3) Make sure you can afford an OH

4) Base your purchase decision on everything else.

 

Six years ago I was in a similar situation when I bought my F; 2100 SMOH.  I was more comfortable with the fact the plane had been consistently flown around 100 hours a year for the last 13 years than anything else.  I could afford an OH so I went ahead with the purchase. No regrets.

How many hours on that engine now?  That’s awesome!

[MikeOH]

Just now, Ragsf15e said:

How many hours on that engine now?  That’s awesome!

Coming up on 2600.  7 hours/qt. Compressions consistently in the high 70s. No signs of metal at oil changes.  I'm in no rush to OH until it starts 'talking to me'.

[N201MKTurbo]

3 minutes ago, MikeOH said:

Coming up on 2600.  7 hours/qt. Compressions consistently in the high 70s. No signs of metal at oil changes.  I'm in no rush to OH until it starts 'talking to me'.

If it ain't broke, don't fix it!

[MikeOH]

1 minute ago, N201MKTurbo said:

If it ain't broke, don't fix it!

EXACTLY!  As you said earlier, hard parts don't just break because of wear/age.

The whole TBO concept is flawed IMHO.  There is nothing 'magic' about crossing 2000 hours where you are suddenly on 'borrowed time'

[Shiroyuki]

13 hours ago, N201MKTurbo said:

The things that make an engine quit in flight are generally fuel and spark related. not the hard metal parts. when the hard metal parts fail it is generally oil related, not wear related. As long as there is oil in the sump and fuel in the tanks and the mags keep making spark, the engine has a very high likelihood of taking you where you want to go.

I see. Thanks for the advice.

[Pinecone]

21 hours ago, Shiroyuki said:

Regarding the overhaul, yes it is at the top of my budget, and I’m aware that it might need an overhaul any day now. 

I do have extra cash in hand just enough for a fresh overhaul, I wouldn’t even consider purchasing this airplane if I don’t have the money to overhaul it. But if i have the engine overhaul today that would leave me no other money for other repairs if something else go wrong, like if i have to reseal the tanks. If the engine could run for another two year I would be more comfortable with doing the overhaul. By the time it’s likely that i would also got an upgrade to left seat at my company.

i did check the books and it says tanks for resealed on 2005. Corrosion shouldn’t be an issue since the plane is hangared all its life. My mechanic seems to know what he’s doing and he has my trust on inspecting those.

There is more to the cost of overhauling the engine, than the overhaul costs.  The engine mount may need some work.  It would be smart to change out all the hoses and the mount pucks.   Also, with a field overhaul are they overhauling or replacing the mags and other things?   A factory reman replaces all of those, but for a price.

As has been said, corrosion is the big concern.  Make sure you have inspected by someone who knows where to look on a Mooney.

 

[LANCECASPER]

On 2/25/2024 at 9:56 AM, Shiroyuki said:

Corrosion shouldn’t be an issue since the plane is hangared all its life.

Don't count on it. Mice love to find their way into airplane hangars to get out of the elements and they find their way into your landing gear and get up on the spar and urinate. Their urine is extremely corrosive and if the urine remains for years it could total the wing and maybe the airplane.