Thoughts on revitalizing an under-utilized M20J?

[N9201A]

And I agree with those who say to budget for the worst and that underutilized "great deals" sometimes can be not so great. Factor in that you're buying the plane to fly it. Why spend the money to buy an aircraft and then not be able to fly it? Sadly, there are enough often-flown, carefully looked-after birds out there to take a chance on something unless the numbers pencil out as irresistible ... AND you're OK being down for a couple months if the worst happens.

[N9201A]

I mean sadly for the sellers and GA generally that it's a buyer's market. Not sad for buyers!

[Cruiser]

It seems to me that it is ALWAYS a buyers market in that the buyer is the one that agrees to a price.

The seller can ask for anything but he will only get what a buyer is willing to pay.

[N9201A]

Using your definition that would be true. I don't know you so I was using Merriam-Webster's and the common real estate, investment and airplane owners' one.

[N9201A]

But if yours works for you...

[Yetti]

For those that say "ya go ahead and pull a couple cylinders" have probably never done it.   It is a couple three days worth of work.  The plane is now in the questionable maintenance zone and can only be flown above the airport for a couple of hours. Are you going to do that when you pick it up?  If you do find one cylinder that is out of spec, do you send it out and wait to get it back?  Meanwhile the seller can't sell to other buyers because his plane is apart in a mechanics shop.   If the cam is bad, who pays for the teardown and rebuild?  If it is good, then you spent alot of money to take the plane to the questionable maintenance zone. 

Not saying it is bad idea from the buyers side, but it throws a bunch of risk on the sellers side.

[JCD]

On 8/28/2016 at 9:57 AM, jetdriven said:

Set aside 10-15k  for first year items and a 30-60% chance of needing an early overhaul for 25-30k. Then do the numbers. 

Byron is 100% spot on.  I am in a similar scenario right now bought a M20 J 201 had not been flow a lot over the last 3 years and after an  $3000 in misc repair and maintenance followed by $8,000 annual I am now having to do a engine overhaul. I have flown the plane 88 hours!   My advise buy a plane that has been flown a lot.  Planes that are being used regularly are a safer bet. Planes that sit are a money pit!

 

check out those lifters and Cam!

 

[ArtVandelay]

Byron is 100% spot on.  I am in a similar scenario right now bought a M20 J 201 had not been flow a lot over the last 3 years and after an  $3000 in misc repair and maintenance followed by $8,000 annual I am now having to do a engine overhaul. I have flown the plane 88 hours!   My advise buy a plane that has been flown a lot.  Planes that are being used regularly are a safer bet. Planes that sit are a money pit!
 
check out those lifters and Cam!
 

Im curious, did you see metal in your oil filter or did you have the oil tested?

[JCD]

2 minutes ago, teejayevans said:

Im curious, did you see metal in your oil filter or did you have the oil tested?

No metal in oil filter and oil analysis all looked good.  

[MyNameIsNobody]

2 hours ago, JCD said:

Byron is 100% spot on.  I am in a similar scenario right now bought a M20 J 201 had not been flow a lot over the last 3 years and after an  $3000 in misc repair and maintenance followed by $8,000 annual I am now having to do a engine overhaul. I have flown the plane 88 hours!   My advise buy a plane that has been flown a lot.  Planes that are being used regularly are a safer bet. Planes that sit are a money pit!

 

check out those lifters and Cam!

 

True dat.  Been there "lived that"...

[ArtVandelay]

No metal in oil filter and oil analysis all looked good.  

So that implies that the spalling stopped or at least slowed when you started flying it, I wonder how many more hours it had left on it.

My untrained eyes don't see anything wrong with the cam, can someone point out what I should be looking at?

[Guest]

2 hours ago, teejayevans said:

So that implies that the spalling stopped or at least slowed when you started flying it, I wonder how many more hours it had left on it.

My untrained eyes don't see anything wrong with the cam, can someone point out what I should be looking at?

In many cases the spalled lifter are the intake which share the common lobe.  The rough surface of the lifter face grinds down the lobe.  If you could look at it in profile you would see that the total height of the lobe is smaller.  In many cases of cam and lifter failure the metal is found in the filter before oil analysis raises the alarm.

Clarence

[bonal]

1 hour ago, M20Doc said:

In many cases the spalled lifter are the intake which share the common lobe.  The rough surface of the lifter face grinds down the lobe.  If you could look at it in profile you would see that the total height of the lobe is smaller.  In many cases of cam and lifter failure the metal is found in the filter before oil analysis raises the alarm.

Clarence

Those photos are scarier than any horror flick you could see, so if there might not be any metal in the filter and an oil analysis might not show evidence of a failing cam what if any would be signs that this condition exists short of a cylinder that quits firing. I would think a compression check would not reveal anything. Is there any way to inspect short of pulling jugs

[Guest]

6 minutes ago, bonal said:

Those photos are scarier than any horror flick you could see, so if there might not be any metal in the filter and an oil analysis might not show evidence of a failing cam what if any would be signs that this condition exists short of a cylinder that quits firing. I would think a compression check would not reveal anything. Is there any way to inspect short of pulling jugs

There will be metal will be in the filter, it's a matter of looking for it and using a strong magnet to draw it out of the media.

Clarence

[bonal]

11 hours ago, JCD said:

No metal in oil filter and oil analysis all looked good.  

So how is this possible unless the failure is sudden and happens right after a clean oil inspection 

[Yetti]

this is all fun talk about valves.... but I thought the original poster said the engine was roller valve.  Does anyone have experience with a roller tappet engine sitting?

[jetdriven]

11 minutes ago, Yetti said:

this is all fun talk about valves.... but I thought the original poster said the engine was roller valve.  Does anyone have experience with a roller tappet engine sitting?

I'm sure they sit but very little or almost no evidence of them failing 

[Guest]

If lack of use and environmental conditions cause corrosion of internal engine parts and corrosion pitting of the lifter face is the cause of camshaft lobe failure, I can't see how a roller tapped engine will be immune to the same type of failure.

Clarence

[jetdriven]

Well for one thing the roller is steel instead of cast iron, and even if it gets corrosion pits the lifter rolls on the cam and can have a long life and perhaps never fail for that reason.  Flat lifters slide and any compromise to that perfect surface sets up for spalling.  I think a roller can won't fail from spalling, it doesn't slide. 

These roller cams have been out for 11 years now and I have yet to see a mournful owner post pictures of a failed one. In fact, I've only seen a couple pictures of roller cams with damage, one of which was stored in a wet basement for a year.  On the other hand, I can't count the number of flat tappet cam owners, even just on this board, replacing engines due to spalling. Some are on their third go-round in a few hundred hours.

the factory exchange engine is not the cheapest solution, it's actually the highest cost, unless you have to re-do your engine twice, then it's the second most expensive option.

The roller cam solution may not be indestructible, nothing is. But it's a heckuva lot better than than what's second place. 

Edited October 9, 2016 by jetdriven