How big of a hit is my wallet about to take?

Well… Yesterday I was changing my oil and I found copper…

I removed the engine and tore it down (with the supervision of an IA that I’m working under)

Center main bearing let go, case is scored on one of the cam journals, crank is within limits but it already has M10 bearings.

Does anyone know the details regarding the m20 STC listed on aircraft specialties’s website?

I think this was an issue when I got the airplane, it just manifested itself in other things. Everything in the top end looked great, once we split the cases though it was all over lol
 
To keep everyone updated, I’m currently waiting on the crank to be repaired @ Aircraft Specialties. They need to re-plate the prop flange which takes 5 weeks by itself.

10 week turnaround all in is what I’ve been told.

Outside of that, the case and lifters took a pretty bad beating.

Plan for now is to overhaul and fly it for a few hundred hours. I’m not really wanting to keep a Cessna 150 forever, and I’m in it right so I’ll be selling next spring sometime ideally.

Pics of carnage below ⬇️
 

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So do you have an answer yet? (to your title)
or a better estimate?
2k for crankshaft repair ≈ 1k for the main bearings, we’ll see but likely 2-3k to repair the case or replacement, call it another 1k in gaskets and misc, I’m going to overhaul the cylinders so that saves 4K ish right there.

No labor because I’m doing it myself which helps.

Haven’t gotten any invoices from machine shop yet so it’s hard to gauge at this point.

If I topped it with millennium cylinders and had them ported by LYCON it would be 15-17k all in for the overhaul. But I’m not really wanting to go that route. (Lipstick on a pig)
 
So I'm very familiar with what BOAT stands for.... Break Out Another Thousand.

Is there an equivalent to that in the aircraft world that I haven't heard yet?


(yeah, I'm kindof new in that world.... I did propose to my wife in a helicopter though, with another airplane involved, so that counts for something, right? ;) )
 
So I'm very familiar with what BOAT stands for.... Break Out Another Thousand.

Is there an equivalent to that in the aircraft world that I haven't heard yet?


(yeah, I'm kindof new in that world.... I did propose to my wife in a helicopter though, with another airplane involved, so that counts for something, right? ;) )

A(viation)M(onetary)U(nit) = $1000
 
I purchased a Cessna 150 with an o-200 late last year, the engine has 700ish hours since factory new from Continental but it has sat for quite a while.

We went ahead and replaced the accessory housing, oil pump gears, cover and oil pressure relief valve as it was having a hard time staying primed.

It’s flown probably 25 hours since I got it, runs like a top, all the cylinders are in the upper 70s and overall it’s been very reliable for me.

A few weeks ago on an 85 degree day I was doing touch and goes and on the 4th lap around the pattern I saw oil pressure indications that I didn’t like.

It was leaned for max rpm, and we were climbing out at VX to stay close to the airport.

At idle it would sit right below the red line, in flight at 1400rpm it would sit right above the red, and in cruise with full throttle it would sit just below the green.

I know in these small continentals, oil pressure issues are kind of a common thing.

I keep reading mixed opinions as to what to expect. Continental manual says 10psi min @ idle, 30psi in cruise. Every gray haired A&P I’ve talked to says “it’ll run past TBO don’t worry about it”

I’ve attached photos of the indications we were getting. I’m not thrilled about them.
First get a KNOWN GOOD mechanical gauge on a short hose, find an oil tap on the engine (probably 1/8 npt) and compare readings to the cockpit gauge. Probably you're seeing good pressure when cool, poor pressure when hot. If oil filter is not showing metal don't worry
 
First get a KNOWN GOOD mechanical gauge on a short hose, find an oil tap on the engine (probably 1/8 npt) and compare readings to the cockpit gauge. Probably you're seeing good pressure when cool, poor pressure when hot. If oil filter is not showing metal don't worry
Read a little further down in the thread, it was talking to me. Fortunately I kept an eye on it and the crank was repairable.
 
Just an update,
All of the parts minus the lifter bodies were repairable.

After inspecting the cylinders, I found that they have low enough serial numbers to be affected by the AD for cracks, beyond that the valve guides are junk, the valves actually had guide material embedded in them.

So I ordered a set of millennium cylinders.

Here’s more carnage pics.
71C7396C-8411-4520-9BD5-C8B950980211.jpeg
A97B5C2A-061F-4472-B117-AC1113D0FC8B.jpeg
 

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Glad you’re able to get it sorted out. When can it get back in the air?
 
Glad you’re able to get it sorted out. When can it get back in the air?
Next weekend I’ll begin re-assembly. That shouldn’t take more than a week or two assuming I’ve got all the parts I need.

The airplane is due for annual Jan 1st so while I’m installing the engine I’ll take care of that.

I’m hoping to be flying by Christmas but it’s likely that it’ll take until early January as we’re pretty stacked up with super cub restoration projects.
 
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