Cyllinder base oil leak, repair or defer?

Checkout_my_Six said:
depends....leaks is a relative term. Technically....they all leak....some more than others.
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There's dumb, and really dumb.

Ya ever stop to think, that you can't have a fire with out fuel? Go ahead add fuel and wait, sooner or later :)

Have an induction fire with a cowl full of oil,,,, yep that's where ya want to be
 
Tom-D said:
There's dumb, and really dumb.

Ya ever stop to think, that you can't have a fire with out fuel? Go ahead add fuel and wait, sooner or later :)

Have an induction fire with a cowl full of oil,,,, yep that's where ya want to be
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think about it....Pal. ;)
 
Tom-D said:
or other methods, techniques, and practices acceptable to the Administrator,
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Ah, so an approval from the fsdo or perhaps other appropriate authority. Just wondering how often that would occur.
 
Let'sgoflying! said:
Ah, so an approval from the fsdo or perhaps other appropriate authority. Just wondering how often that would occur.
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FSDO need not get involved. Lots of shops have authorized repair procedures.
 
Let'sgoflying! said:
but even they must have gotten approval from someone.
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Not necessarily, many independent shops just do what they think best, it really is a minor alteration.
read FAR 43.2

I don't even say I complied with the overhaul manual in my sign offs.

This engine meets FAR 43.2 for ZERO since major at total time of XXXX as rebuilt to new standards.
With the following parts reworked or replaced
then the list.
Remember the overhaul manual tells you to do a lot of things we no longer do, we no longer rebuild cylinders we use after market, So how can you use the OM when you really didn't do the things in it?
All the FARs require is a description of work done
 
Dan Thomas said:
Yup. That's the usual problem. Aging seals.
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Tom-D said:
Not necessarily, many independent shops just do what they think best, it really is a minor alteration.
read FAR 43.2

I don't even say I complied with the overhaul manual in my sign offs.

This engine meets FAR 43.2 for ZERO since major at total time of XXXX as rebuilt to new standards.
With the following parts reworked or replaced
then the list.
Remember the overhaul manual tells you to do a lot of things we no longer do, we no longer rebuild cylinders we use after market, So how can you use the OM when you really didn't do the things in it?
All the FARs require is a description of work done
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Repair Stations cannot do whatever they feel like and implying they can is false.
 
Isn't there an AC out there concerning methods, techniques, and practices acceptable to the administrator? I don't know if the sealing of crank cases is in there, but it may well be.
 
bnt83 said:
Repair Stations cannot do whatever they feel like and implying they can is false.
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Many shops are not repair stations, they are just A&Ps

Repair stations can develop their own procedures. The FAA does not dictate procedures they only approve or not.
 
Tom-D said:
shops just do what they think best
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Wow, I had no idea a person could do whatever they wanted.
Honestly I would be really uncomfortable with that.
Or even flying an engine like that which someone else had done that way.
Have to wonder if that's what happened with people putting RTV on the cylinder bases, and the disaster that was.
 
Tom-D said:
Many shops are not repair stations, they are just A&Ps

Repair stations can develop their own procedures. The FAA does not dictate procedures they only approve or not.
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I'm well aware of repair station procedures, you are not. Developing a written procure is a lot more than making up stuff out of thin air. Since a repair station RSGOM dictates how a station will operate, those proprietary procedures are likely FAA approved and took a lot longer to get then you are aware of. Some of the ones I'm familiar with took years to get approved.
 
charlie said:
I agree. A failure waiting to happen. Hard to believe anyone could be stupid enough to use something like that let alone show it off! WHY?
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The original engine oil screen remained installed despite the fact the engine was equipped with an oil filter. The oil screen was removed and it was noted that there was a significant amount of contaminates consistent with metallic material as well as a significant amount of unidentified black colored substance.

The crankcase was intact and undamaged. The crankcase halves were split and the crankcase was visually inspected. It was noted that there was black sealant applied to the crankcase halves mating surfaces and there was no silk thread noted on the crankcase halve mating surfaces. It was also noted that the black sealant material was found in several of the oil galleys.

When Mr. Downey was asked what the black sealant substance was found on the cylinders and the crankcase during an examination of the engine and airframe on October 15, 2016, he replied that it was #2 Permatex. Mr. Downey said that it was a non-hardening substance, so if it goes through an oil pump it will not clog a passageway.

When Mr. Downey was informed as to why the black sealant, #2 Permatex, was not applied to the #2 cylinder, he replied that he omitted to apply the compound. He had to reason as to why it was not applied, just that it was omitted.
 
bnt83 said:
I'm well aware of repair station procedures, you are not. Developing a written procure is a lot more than making up stuff out of thin air. Since a repair station RSGOM dictates how a station will operate, those proprietary procedures are likely FAA approved and took a lot longer to get then you are aware of. Some of the ones I'm familiar with took years to get approved.
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Who said any thing was made up out of thin air? once again you over react to a simply statement.
The FAA certainly doesn't make up repair procedures, the Repair station does, who cares how long it takes to gain approval, That's just the FAA way.
Would you like the FAA to tell you how you to do anything? they either approve your procedure or not, if not, you get to try again.

And OBTW, if you are so well educated about repair procedures, tell us about A&Ps in the field, placing a sealant on case half.
 
Let'sgoflying! said:
Wow, I had no idea a person could do whatever they wanted.
Honestly I would be really uncomfortable with that.
Or even flying an engine like that which someone else had done that way.
Have to wonder if that's what happened with people putting RTV on the cylinder bases, and the disaster that was.
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When sealing cases, common sense goes a long ways.
I recently tried to separate a case that some one had epoxied together, I'll give them credit, it never leaked. But getting it apart ruined the case.
 
slacktide said:
The original engine oil screen remained installed despite the fact the engine was equipped with an oil filter. The oil screen was removed and it was noted that there was a significant amount of contaminates consistent with metallic material as well as a significant amount of unidentified black colored substance.

The crankcase was intact and undamaged. The crankcase halves were split and the crankcase was visually inspected. It was noted that there was black sealant applied to the crankcase halves mating surfaces and there was no silk thread noted on the crankcase halve mating surfaces. It was also noted that the black sealant material was found in several of the oil galleys.

When Mr. Downey was asked what the black sealant substance was found on the cylinders and the crankcase during an examination of the engine and airframe on October 15, 2016, he replied that it was #2 Permatex. Mr. Downey said that it was a non-hardening substance, so if it goes through an oil pump it will not clog a passageway.

When Mr. Downey was informed as to why the black sealant, #2 Permatex, was not applied to the #2 cylinder, he replied that he omitted to apply the compound. He had to reason as to why it was not applied, just that it was omitted.
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You should also note the FAA had no problem with the sealant, they simply made note of it.
and did not blame the sealant for the failure. And you forgot to note this was an owner build.
 
charlie said:
I agree. A failure waiting to happen. Hard to believe anyone could be stupid enough to use something like that let alone show it off! WHY?
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The engine in the picture is a E/AB engine with data tag removed and is now flying in Canada on a VariEZ. And flying very well I might add.
 
Tom-D said:
You should also note the FAA had no problem with the sealant, they simply made note of it.
and did not blame the sealant for the failure.
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It was an NTSB investigation, not an FAA investigation. They blamed other sloppy workmanship for the failure.

The National Transportation Safety Board determines the probable cause(s) of this accident to be:
The loss of engine power due to the mechanic's inadequate tightening of the crankshaft gear
retaining bolts during an engine overhaul, which resulted in fatigue failure of the bolts and the
crankshaft gear dowel pin that allowed the crankshaft gear to separate from the crankshaft.


Tom-D said:
And you forgot to note this was an owner build.
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Sounds like you forgot to tell the NTSB that. The record indicates that you told them that you did the work. Also, it's your signature in the logbook.

When Mr. Downey was asked if he had a calibrated torque wrench, and if he used it to install the crankshaft gear, he replied “YES” to both questions.

Mr. Downey was asked if any of the accessories were sent out to other vendors during the engine overhaul process, specifically the starter, carburetor, and magnetos. Mr. Downey replied that during the entire overhaul process no components were sent out, that some were inspected and repaired by himself.

Mr. Downey was asked by the IIC what manual or instructions did he use to overhaul the accident airplane’s engine. Mr. Downey replied he used the Continental O-200 Overhaul Manual, which was dated January, 1984, which was the date of approval by the Federal Aviation Administration.
 
slacktide said:
The original engine oil screen remained installed despite the fact the engine was equipped with an oil filter. The oil screen was removed and it was noted that there was a significant amount of contaminates consistent with metallic material as well as a significant amount of unidentified black colored substance.

The crankcase was intact and undamaged. The crankcase halves were split and the crankcase was visually inspected. It was noted that there was black sealant applied to the crankcase halves mating surfaces and there was no silk thread noted on the crankcase halve mating surfaces. It was also noted that the black sealant material was found in several of the oil galleys.

When Mr. Downey was asked what the black sealant substance was found on the cylinders and the crankcase during an examination of the engine and airframe on October 15, 2016, he replied that it was #2 Permatex. Mr. Downey said that it was a non-hardening substance, so if it goes through an oil pump it will not clog a passageway.

When Mr. Downey was informed as to why the black sealant, #2 Permatex, was not applied to the #2 cylinder, he replied that he omitted to apply the compound. He had to reason as to why it was not applied, just that it was omitted.
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The accident that Slack is talking about is still in litigation so I'm not at liberty to discuss it, But I can tell you that I have been totally exonerated from any liability in this engine failure. The suit is not toward me, it is between plaintiff and the major parts supplier.
The fact is, when the plaintiff's lawyer sued the NTSB for the parts, after a year they sent them back, they were then sent to a lab in Canada for analyzing, the 4 bolts that failed showed a Rockwell hardness of 18-20 (a grade 5 bolt is higher than 25).
take a look at
http://veteranflyg.se/wordpress/wp-...-C75-C85-C90-O-200-Parts-Catalog-Aug-2011.pdf
see figure 5 item 11, see there two part numbers, see the notes?

those two part number are what this lawsuit is all about.
The NTSB never did a harness test on the bolts, just a visual and made an opinion (a wrong one) The bolts did stretch, soft bolts do that. These two part numbers look exactly alike, there are no head markings. The packing we got had the correct part number but not the correct bolt.
And that is what the parts supplier and the company that supplied them are trying to figure out who will pay and how much.
My Friend (the plaintiff) and his wife are doing well and are back flying.
 
The National Transportation Safety Board determines the probable cause(s) of this accident to be:
The loss of engine power due to the mechanic's inadequate tightening of the crankshaft gear
retaining bolts during an engine overhaul, which resulted in fatigue failure of the bolts and the
crankshaft gear dowel pin that allowed the crankshaft gear to separate from the crankshaft.

And their determination has been proven wrong in court to every ones approval. they did not do the whole job.
 
but you said you weren't gonna comment on it...and you did.o_O
Tom-D said:
The accident that Slack is talking about is still in litigation so I'm not at liberty to discuss it, But I can tell you that I have been totally exonerated from any liability in this engine failure. The suit is not toward me, it is between plaintiff and the major parts supplier.
The fact is, when the plaintiff's lawyer sued the NTSB for the parts, after a year they sent them back, they were then sent to a lab in Canada for analyzing, the 4 bolts that failed showed a Rockwell hardness of 18-20 (a grade 5 bolt is higher than 25).
take a look at
http://veteranflyg.se/wordpress/wp-...-C75-C85-C90-O-200-Parts-Catalog-Aug-2011.pdf
see figure 5 item 11, see there two part numbers, see the notes?

those two part number are what this lawsuit is all about.
The NTSB never did a harness test on the bolts, just a visual and made an opinion (a wrong one) The bolts did stretch, soft bolts do that. These two part numbers look exactly alike, there are no head markings. The packing we got had the correct part number but not the correct bolt.
And that is what the parts supplier and the company that supplied them are trying to figure out who will pay and how much.
My Friend (the plaintiff) and his wife are doing well and are back flying.
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Slack is totally wrong on this he only knows what he read in a report that has been proven wrong.
 
Checkout_my_Six said:
but you said you weren't gonna comment on it...and you did.o_O
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Yeah and will probably catch hell for it too.

IMHO had the NTSB done a proper job and hardness tested the bolts, we wouldn't be here there would probably be an AD on every 0200/0300 that could possibly have these bolts in them.
 
And to add, the proper bolt for the 0-200/0-300 is a grade 8 bolt. (you saw the part number) and the funny thing is there are none in the supplier's supply source.
Same Same = Rod bolts.
 
Tom-D said:
You should also note the FAA had no problem with the sealant, they simply made note of it.
and did not blame the sealant for the failure. And you forgot to note this was an owner build.
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Owner build, but going into a plane that isn't an experimental. Wouldn't an A&P need to sign off on that engine?
 
Cap'n Jack said:
Owner build, but going into a plane that isn't an experimental. Wouldn't an A&P need to sign off on that engine?
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Yes, why do you believe I was even involved, the owner did the torque, I watch and safety wired the bolts. two people involved, Snap-On torque wrench calibrated the week prior.
You guys had me convinced I screwed the pooch on this, And I lost a hell of a lot of sleep thinking I had some how hurt a dear friend, But no, thanks to a great diligent lawyer (blood hound). we find that we were f- with bogus bolts.
 
Tom-D said:
Yes, why do you believe I was even involved, the owner did the torque, I watch and safety wired the bolts. two people involved, Snap-On torque wrench calibrated the week prior.
You guys had me convinced I screwed the pooch on this, And I lost a hell of a lot of sleep thinking I had some how hurt a dear friend, But no, thanks to a great diligent lawyer (blood hound). we find that we were f- with bogus bolts.
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It seems the bolded parts contradict one another.
 
Tom-D said:
OMG your mechanic is a freaking idiot, Doesn't he/she know the cylinders are held on by thru case bolts? The only ways for a cylinder base to leak is for a cylinder hold down stud or a cylinder thru case bolt to be loose. the only way they get loose is to stretch them. How do you stretch them? detonation!
GET that engine off of there and get it rebuilt, before it kills you.
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"Detonation". You clearly have no clue what happens inside an engine.
(No, detonation never happens inside a piston engine, but I'll humor the incorrect term for this).

Just FYI: It has NOTHING to do with stretching bolts.
Knocking/detonation/whatever you want to call it happens AFTER the combustion event. The peak pressures caused by it aren't different in a meaningful way to cause issues.
Sorry, don't call people freaking idiots, when you have no clue what you are talking about.
 
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This is how I was taught concernign detonation

Detonation causes a very high, very sharp pressure spike in the combustion chamber but it is of a very short duration. If you look at a pressure trace of the combustion chamber process, you would see the normal burn as a normal pressure rise, then all of a sudden you would see a very sharp spike when the detonation occurred


KEY DEFINITIONS
Detonation: Detonation is the spontaneous combustion of the end-gas (remaining fuel/air mixture) in the chamber. It always occurs after normal combustion is initiated by the spark plug. The initial combustion at the spark plug is followed by a normal combustion burn. For some reason, likely heat and pressure, the end gas in the chamber spontaneously combusts. The key point here is that detonation occurs after you have initiated the normal combustion with the spark plug.

Pre-ignition: Pre-ignition is defined as the ignition of the mixture prior to the spark plug firing. Anytime something causes the mixture in the chamber to ignite prior to the spark plug event it is classified as pre-ignition. The two are completely different and abnormal phenomenon.
 
1RTK1 said:
This is how I was taught concernign detonation

Detonation causes a very high, very sharp pressure spike in the combustion chamber but it is of a very short duration. If you look at a pressure trace of the combustion chamber process, you would see the normal burn as a normal pressure rise, then all of a sudden you would see a very sharp spike when the detonation occurred


KEY DEFINITIONS
Detonation: Detonation is the spontaneous combustion of the end-gas (remaining fuel/air mixture) in the chamber. It always occurs after normal combustion is initiated by the spark plug. The initial combustion at the spark plug is followed by a normal combustion burn. For some reason, likely heat and pressure, the end gas in the chamber spontaneously combusts. The key point here is that detonation occurs after you have initiated the normal combustion with the spark plug.

Pre-ignition: Pre-ignition is defined as the ignition of the mixture prior to the spark plug firing. Anytime something causes the mixture in the chamber to ignite prior to the spark plug event it is classified as pre-ignition. The two are completely different and abnormal phenomenon.
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You were taught wrong.

Detonation is _supersonic_ combustion. The process is _ALWAYS_ subsonic = deflagration, never detonation. The flame front NEVER exceeds the speed of sound. Detonation is an old term that was used when people had no idea what actually was going on.

The reason why it damages things is not the pressure, but that it breaks the boundary layer protecting the surfaces inside the combustion chamber.
The compression these engines run cannot produce "super knock" that might have a meaningful difference in cylinder pressures. Normal knock isn't that much higher than normal cycle.
 
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Can you cite a reference.
I’ve seen graphs of engine monitors where temps runaway very quickly in airplanes. What is your reason for that? Detonation or pre-ignition
 
1RTK1 said:
Can you cite a reference.
I’ve seen graphs of engine monitors where temps runaway very quickly in airplanes. What is your reason for that? Detonation or pre-ignition
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What temps? CHTs or EGTs?
 
1RTK1 said:
View attachment 66434

According to testing cylinder pressures do rise
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That's what's called "super knock", it won't happen inside an O200. Maybe a highly stressed turbocharged engine, but not a N/A engine. To have that sort of effect, you've had a thermal runaway inside the cylinder chamber.
 
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