Engine overhaul

[jetdriven]

It was definitely an engine issue, and single engine was not a problem, and the props were both  balanced too and it still did it. 

[Browncbr1]

I spoke with the shop today because I wanted more details on the cracked cylinder….  Specifically wanted to verify that the cylinders were magnafluxed.  He confirmed all had been dye penetrant inspected.  He was able to get a new cylinder off the shelf from an industry friend for $700. I was happy to hear that.    He also told me that one of my connecting rods was cracked.  Holy chit!   In any case, things are put together and he’s getting close to running it on the test stand.  
 

[carusoam]

See if you can get a pic of the cracked connecting rod…

That sounds semi-mortal, waiting for the crack to propagate…

Nice catch by the guy who found that…

PP thoughts only,

-a-

[Browncbr1]

17 hours ago, carusoam said:

See if you can get a pic of the cracked connecting rod…

That sounds semi-mortal, waiting for the crack to propagate…

Nice catch by the guy who found that…

PP thoughts only,

-a-

Here are pictures of the cracks.  
the rod crack is lengthwise.  The cylinder crack is pretty high up in the stroke, which he said is strange.  He had only seen the crack lower near the flange and had never seen a cracked barrel on an angle valve head.  

 

Edited March 5, 2022 by Browncbr1

[201Steve]

Can’t see pics

[Browncbr1]

19 minutes ago, 201Steve said:

Can’t see pics

Fixed

[carusoam]

Eagle Eye award to the mechanic who spotted those anomalies… !

Thanks for sharing the pics.

Go MS!

Best regards,

-a-

[EricJ]

That rod crack is huge.    How did they find the barrel crack?   I'd think that'd be tough to see with either magnaflux or dye pen.

 

[jetdriven]

Are you sure that rod is cracked? Magnaflux will tell you for sure, that’s the way engine shops check them. 

[Browncbr1]

9 hours ago, jetdriven said:

Are you sure that rod is cracked? Magnaflux will tell you for sure, that’s the way engine shops check them. 

He said the rod was rejected from a third party inspection, I understand it was magnafluxed..  the shop that did the crank also did the rods..  he said he tried to look at the crack using a 10x scope, but couldn’t see it.   The barrel crack they were able to see after honing.  It wasn’t visible after disassembly.  

Edited March 6, 2022 by Browncbr1

[Browncbr1]

11 hours ago, EricJ said:

That rod crack is huge.    How did they find the barrel crack?   I'd think that'd be tough to see with either magnaflux or dye pen.

 

The barrel crack was found visually after honing.  He confirmed all cylinders, including the new one were carefully inspected with dye penetrant though.  
 

the only think I can think of causing the cylinder crack is shock cooling.  I did do some training on this engine years ago.  No telling how long these cracks have been there.  

[A64Pilot]

Sometimes cracks are internal and not even open to the surface, magnetic particle inspection will find some of these cracks as will ultrasound and eddy current, x-ray but dye penetrant will not

[Old Chub]

The crack indication is most likely a forging lap as it is not oriented in a direction the rod would see tension (that would create a fatigue crack).   However, I have always said (and especially in cases of aircraft engine rotating components) " when in doubt, junk it out"   

Best to replace and move forward with confidence.

 

 

 

[Browncbr1]

The engine shipped out to me on Friday.  Should have it this week.  Here is a video of it running on the test stand while it was warming up.  He ran it at high MP for about 40 minutes.  
 

I’ll post a $ total detail break down later this week.  I had to order a new oil cooler, as they said mine old one was beyond repairable.  

[201Steve]

Not what I had in mind for a test cell, but I guess it does the trick!! Do they change oil and filter after the run/before shipping or does it stay with it for a bit longer?

[Browncbr1]

3 hours ago, 201Steve said:

Not what I had in mind for a test cell, but I guess it does the trick!! Do they change oil and filter after the run/before shipping or does it stay with it for a bit longer?

It’s basically an operations and leak checking run.  Seems he also set the idle speed and mixture for the new servo as well.  I still have to break it in..   yea, it’s not a dyno, and I knew that going in.  I just wanted to make sure it’s running good and no leaks before shipment.   I didn’t want to have to ship and install on the plane to find out if something was wrong.    
 

I don’t think the oil or filter were changed after.   I understand that happens at 10hrs.  

Edited March 20, 2022 by Browncbr1

[carusoam]

Way cool!

Needs a few more things for the next run…

1) A dog house (improved cooling)

2) A JPI (great data collecting)

3) A steering wheel (to drive the test stand down the runway!)

4) capture 0 to Vr times in seconds…

That would make the ground runs fun!

Great video Mr. Brown!

Thanks for sharing it.

Best regards,

-a-

[jetdriven]

On 3/20/2022 at 1:09 PM, Browncbr1 said:

The engine shipped out to me on Friday.  Should have it this week.  Here is a video of it running on the test stand while it was warming up.  He ran it at high MP for about 40 minutes.  
 

I’ll post a $ total detail break down later this week.  I had to order a new oil cooler, as they said mine old one was beyond repairable.  

I would be really concerned about running an Engine at high manifold pressure without some kind of air deflector or scoop on top of it to force air through the fins. 

[Browncbr1]

It showed up day.   In a well built new wood crate.  Starting install tomorrow. 

[Browncbr1]

1 hour ago, jetdriven said:

I would be really concerned about running an Engine at high manifold pressure without some kind of air deflector or scoop on top of it to force air through the fins. 

Yea….  Not everything has gone as expected..    I don’t know for certain how long and how hard it was really run.  In the beginning, he said he would have CHT probes on every cylinder.   I don’t see them in the video.  Not sure

Edited March 21, 2022 by Browncbr1

[N201MKTurbo]

They didn't paint it? The service manual for the engine requires that it is painted.

[jetdriven]

21 minutes ago, Browncbr1 said:

Yea….  Not everything has gone as expected..    I don’t know for certain how long and how hard it was really run.  In the beginning, he said he would have CHT probes on every cylinder.   I don’t see them in the video.  Not sure

Who is building the engine?

[Browncbr1]

6 minutes ago, jetdriven said:

Who is building the engine?

Bill Wagner at SkyBoss Aviation in Tulsa 

Edited March 21, 2022 by Browncbr1

[EricJ]

39 minutes ago, Browncbr1 said:

Bill Wagner at SkyBoss Aviation in Tulsa 

Looks awesome and well-packed.   That's a good start.

[Guest]

1 hour ago, Browncbr1 said:

Yea….  Not everything has gone as expected..    I don’t know for certain how long and how hard it was really run.  In the beginning, he said he would have CHT probes on every cylinder.   I don’t see them in the video.  Not sure

I had always understood that in order to be called an Overhaul it had to be run in with a set of calibrated instruments to record engine parameters including temperatures, RPM, MAP.  The oil is to be drained, suction screen and main filter are to be checked after the run.  Drained oil is supposed recorded and compared to starting quantity in order to determine oil use during the run.
 The test club propellers are specific to engine horsepower,  if the engine can turn the prop to a specified RPM, it’s supposed to be making rated HP.

Clarence