Making metal

Norman said:
Given the circumstances and time SMOH on that engine I would NOT sign it off for return to service without a tear-down inspection. Time to bite the bullet and overhaul NOW. It only take one bearing seizure to create a situation your lawyers have warned you about.
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These engines usually do not fail in that manner. they will normally simply loose oil pressure, and generate more metal.

Seizure will occur when a rod is broken and contacts the case, or some thing like that.
 
LDJones said:
Filter pleats were full of itty-bitty bits.

After evaluating the damage it is definitely getting a full teardown and rebuild. :sad: Better safe than sorry.
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I'd like to see pictures of the results of the tear down inspection.
 
.....and any guesses how the oil analysis would turn out?

I bet not clean....:no:


Looks like Tom is taking bets on the crank being trashed......:D
 
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Checkout_my_Six said:
.....and any guesses how the oil analysis would turn out?

I bet not clean....:no:


Looks like Tom is taking bets on the crank being trashed......:D
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That really depends upon what size the crank was at last overhaul.
 
Tom-D said:
These engines usually do not fail in that manner. they will normally simply loose oil pressure, and generate more metal.

Seizure will occur when a rod is broken and contacts the case, or some thing like that.
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unless they don't get all the metal out in the flush and a main oil galley plugs and melts down the bearing. but most the time you are right the oil pressure drops until it seizes.

bob
 
unsafervguy said:
unless they don't get all the metal out in the flush and a main oil galley plugs and melts down the bearing. but most the time you are right the oil pressure drops until it seizes.

bob
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Bearing failures very seldom cause a seizure. Seizure won't occur until you have parts large enough floating around in the crank case to jamb the crank.
 
Tom-D said:
That really depends upon what size the crank was at last overhaul.
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As pulverized as that piston is, I am betting the rod is junk, the crank is trashed from parts beating on the counter weights,, and The case is probably toast for the same reason......:yes:
 
....well, believe it or not.... peening is actually a great stress reliever.... :lol:
 
N801BH said:
As pulverized as that piston is, I am betting the rod is junk, the crank is trashed from parts beating on the counter weights,, and The case is probably toast for the same reason......:yes:
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I don't believe the case was struck with a piece large enough to do it any damage. But I'll bet the rod would not pass inspection to be used again with out rework. At this high time, it will need at minimum a new wrist pin bushing, and rebore of the bearing end. (if it is not too short from previous rework)
 
Tom-D said:
I don't believe the case was struck with a piece large enough to do it any damage. But I'll bet the rod would not pass inspection to be used again with out rework. At this high time, it will need at minimum a new wrist pin bushing, and rebore of the bearing end. (if it is not too short from previous rework)
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I hope the OP posts pics of the autopsy...
 
Before I would return this engine to service I'd have the case lapped & line bored, crank inspected/reworked, buy new cylinders, new cam, new lifter assemblies. Then comply with all SBs required at overhaul. and any other requirements of FAR 43.2.

I just found out how it feels to have one of your engines quit in flight. It is a gut wrenching, beat your self up experience that simply not worth skimping on the maintenance.
 
Tom...I'm betting on something along the lines of pilot error..... Think carb icing
 
Tom-D said:
Before I would return this engine to service I'd have the case lapped & line bored, crank inspected/reworked, buy new cylinders, new cam, new lifter assemblies. Then comply with all SBs required at overhaul. and any other requirements of FAR 43.2.
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At this point a factory reman may be a better option. Let Lycoming deal with what may turn out to be junk.
 
Toast...


Sent from my iPhone using Tapatalk
 
Norman said:
At this point a factory reman may be a better option. Let Lycoming deal with what may turn out to be junk.
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I know Continental only gives credit for a core if it is 'assembled and running when removed'. They dont want a crate with parts and they dont credit for an engine with con-rods sticking out of the case. Not sure how they would treat this kind of internal unplanned disassembly.
 
Norman said:
At this point a factory reman may be a better option. Let Lycoming deal with what may turn out to be junk.
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Oh Hell no. read what a rebuilt engine is. Under or over sized parts as the manufacturer allows.

The next time you think you can overhaul the engine it may simply have parts that can't be reworked again.

Use your own good parts, and replace the worn ones with NEW, you'll have a better engine.
 
Checkout_my_Six said:
Tom...I'm betting on something along the lines of pilot error..... Think carb icing
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Thanks for the positive thinking, but we may not know for up to a year. The NTSB investigator said they will not close the investigation until they interview the pilot, they will not do that until he is off drugs. God knows when that will happen.

In the mean time I have no financing for the clipper project, because we don't know if he will ever fly again, so we won't know if he will want to finish it or not.
Right now every thing is on hold.
 
docmirror said:
Alternate Repair method, sure to be approved by the administrator:

1. Remove affected cylinder, remove rod, piston(parts) pushrods and lifters.
2. Fit a #3 nitrile rubber segment around the affected rod journal, attach with a dab of silicone over the oil hole in journal.
3. Clamp a #3 NAPA hose clamp over the rubber and journal. Tighten hose clamp screw to 4.5 Newton Meters(or so)
4. Reattach old cylinder and pushrod outer tubes with new seals and attach the rocker cover.
5. Derate engine a skosh.

:yikes:
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A friend of mine did this with a 350 in a Chevy van. Removed remains of a throw rod, pushed the piston up, removed the pushrods, sold it. The new owner did a compression test to diagnose the vibration, found 0 compression on one cylinder (imagine that!), blew air in to see if that loosened anything up. Piston went down, contacted crank, engine wouldn't turn over.
 
Barb had a Dodge Dart slant 6 / 225 at about 85k it blew a hole in #1 piston, no knocks just burned oil and smoked like hell. So I pulled the push rods for #1 and drove it on 5 for 20k miles before we traded it.
 
Tom-D said:
Barb had a Dodge Dart slant 6 / 225 at about 85k it blew a hole in #1 piston, no knocks just burned oil and smoked like hell. So I pulled the push rods for #1 and drove it on 5 for 20k miles before we traded it.
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Wow. I'm surprised. Those slant 6's would usually run forever as long as you could keep enough oil in them as the rings wore out. When I was first in college (late 1970's) there was guy that had one with something over 300k miles on it. He installed a small oil tank to keep feeding oil into the crank. It smoked like crazy but it ran pretty smooth and it was cheap.

John
 
jsstevens said:
Wow. I'm surprised. Those slant 6's would usually run forever as long as you could keep enough oil in them as the rings wore out. When I was first in college (late 1970's) there was guy that had one with something over 300k miles on it. He installed a small oil tank to keep feeding oil into the crank. It smoked like crazy but it ran pretty smooth and it was cheap.

John
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Ours was a NY car, it rusted away long before it wore out.
 
What a mess we found inside. Most of the lifters were broken from the metal bouncing around inside.
 

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And it was a broken piston skirt as originally suspected.
 

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The cam didn't fare well, either.

Sorry for the separate posts but iPhone only allows a singe attachment!
 

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Next question:

Is the case salvageable or dd it get beaten to death by flying parts?
 
Norman said:
Next question:

Is the case salvageable or dd it get beaten to death by flying parts?
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Case and crank sent out for testing. All of the cylinder flanges were beat to heck so they're junk. Not much of the original engine will go back in it.
 
LDJones said:
Case and crank sent out for testing. All of the cylinder flanges were beat to heck so they're junk. Not much of the original engine will go back in it.
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It's amazing how quickly an engine will self destruct, this one looks like it was seconds away, glad no one was hurt.
 
PaulS said:
It's amazing how quickly an engine will self destruct, this one looks like it was seconds away, glad no one was hurt.
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Yeah, we're talking a collective minute or two max from first ka-thunk to it being pretty much destroyed. Glad they opted to not fly! The fact that it even ran after all that is fairly amazing.
 
Ok, that engine did not get like that in two minutes from the first 'clunk'.
It has been shedding metal for some time.
Ya might want to develop the habit of checking the oil level (which I know you do) and putting a drop off the stick onto your finger and rubbing it around looking for a silvery sheen.
If so, go back home.
 
Dr. O said:
Ok, that engine did not get like that in two minutes from the first 'clunk'.
It has been shedding metal for some time.
Ya might want to develop the habit of checking the oil level (which I know you do) and putting a drop off the stick onto your finger and rubbing it around looking for a silvery sheen.
If so, go back home.
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Because it's in a training environment it gets 25, 50 and 100 hour checks. So that mean almost weekly checkups. Our mechanic is pretty anal about our engines. That said, helicopter engines take a beating....especially trainers.
 
Dr. O said:
Ok, that engine did not get like that in two minutes from the first 'clunk'.
It has been shedding metal for some time.
Ya might want to develop the habit of checking the oil level (which I know you do) and putting a drop off the stick onto your finger and rubbing it around looking for a silvery sheen.
If so, go back home.
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I respectfully disagree...

I used to own and run a racing engine development company and some of my higher end customers would actually build up some prototype motors and I will blow them up on purpose to find the weak links..

Probably did that 40 -50 times in my life... In almost every case I was able to throttle back, kill the ignition and fuel in maybe 2-3 seconds but the vast majority were completely trashed. Some to the point of not being able to determine the part that failed first during the autopsy....

The ones that were built with not enough bearing clearance would start to exhibit laboring, reduced RPM's and smoke out of the breather.. In those cases I could shut it down in a timely matter to be able to analyze the failed part.... Even those NEVER got half assed rebuilt.. They all got a complete teardown, and I bet 99% never used any old parts on the new prototype motor..

Also,,, people NEVER reuse the oil pumps , filters, lines and coolers since it is industry practice to not try and clean out the metal shaving... IMHO...

I said in a very early post that motor was TOAST...... And it is..... BTDT way too many times...:yes::yes:
 
N801BH said:
I respectfully disagree...

I used to own and run a racing engine development company and some of my higher end customers would actually build up some prototype motors and I will blow them up on purpose to find the weak links..

Probably did that 40 -50 times in my life... In almost every case I was able to throttle back, kill the ignition and fuel in maybe 2-3 seconds but the vast majority were completely trashed. Some to the point of not being able to determine the part that failed first during the autopsy....

The ones that were built with not enough bearing clearance would start to exhibit laboring, reduced RPM's and smoke out of the breather.. In those cases I could shut it down in a timely matter to be able to analyze the failed part.... Even those NEVER got half assed rebuilt.. They all got a complete teardown, and I bet 99% never used any old parts on the new prototype motor..

Also,,, people NEVER reuse the oil pumps , filters, lines and coolers since it is industry practice to not try and clean out the metal shaving... IMHO...

I said in a very early post that motor was TOAST...... And it is..... BTDT way too many times...:yes::yes:
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By the time you saw the failure on the test stand the engine was already toast. and had been that way for a while.

You'd be surprised at how long after the initial failure some of these aircraft engines will run.

But then again when you have a rod bolt failure it's over in 1 revolution. :)

You just never know.
 
Tom-D said:
By the time you saw the failure on the test stand the engine was already toast. and had been that way for a while.

You'd be surprised at how long after the initial failure some of these aircraft engines will run.

But then again when you have a rod bolt failure it's over in 1 revolution. :)

You just never know.
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Yup...

We called that a "OIL PAN FAILURE"..:yikes:..

Ya see,, the pan failed just as the rods, crank and other parts put BIG holes in it..:rolleyes::D.......:redface:
 
For those interested in this saga:

Crankshaft was toast. Case was salvageable and has been reworked, and is on its way back. I think the case is probably the only part that will be reused in the entire engine...perhaps a few accessories.

Sure doesn't take long to trash an engine!
 
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