Engine Making Metal

[merrja]

Hi All,

On an oil change today my trusted a&p noticed steel in oil filter of my mooney .  Any advice on the overhaul?  It's been making metal for <50 hours since that was my last oil change and filter inspection.

 

Thanks,

Jim

[carusoam]

Plan on giving a whole bunch of answers regarding total engine times, time SMOH, your preference for factory reman or lowest cost available.

Which Mooney and/or engine do you have?

Have you done an analysis of the steal to know where it is coming from?

You can also search the same topics at the top of your screen. Don't forget to push the proper forum button...

I went with a factory reman when the time came. There are many ways available to suit your preferences.

Best regards,

-a-

[BigTex]

Hi Jim - How much and what type of engine?

 

Here's what Lycoming has to say about making metal:

 

8. Evidence of metal contamination found in the oil filter element or suction screen requires further examination to determine the cause. Below is a list of recommended actions based on the appearance and approximate quantity of particles found in the oil filter/suction screen.
Continue performing steps a. through d. until there is no further evidence of metal contamination in the oil filter element or suction screen. If at any time the amount of metal contamination equals or exceeds what is stated in steps e. through j. remove engine from service.
a. 1 to 9 small (1/16 inch diameter of less) pieces of magnetic or nonmagnetic metal – change oil filter and clean suction screen, drain oil, and refill. Place aircraft back in service and check oil filter or screen at next scheduled oil change/oil filter replacement.
b. 10 to 20 small (1/16 inch diameter or less) pieces of shiny flake-like, nonmagnetic, or 10 or fewer short hair-like pieces of magnetic material – change oil filter and clean suction screen, drain oil, and refill. Place engine back in service and again check oil filter or suction screen after 25 hours of engine operation.
c. 20 to 40 small pieces as in step b. – change oil filter and clean suction screen, drain oil, and refill. Place the aircraft back in service and check oil filter or suction screen after 10 hours of engine operation.
d. As in step b., but larger amount, such as 45-60 small pieces – change oil filter and clean suction screen, drain oil, and refill. Run engine on ground for 20-30 minutes. Inspect oil filter suction screen. If clean, fly aircraft for 1 to 2 hours and again inspect oil filter/suction screen. If clean, inspect oil filter/suction screen after 10 hours of engine operation.

NOTE
In items e. through j. below, the engine must be removed from service until the source of the metal is determined and corrective maintenance has been accomplished.
e. Pieces of metal ranging in size of broken lead pencil point (1/16 inch diameter) or larger. Remove suction (sump) screen to check for pieces of metal that may have fallen into the sump. In any event, ground aircraft and conduct investigation. A mixture of magnetic and nonmagnetic material in this case often times means a valve or ring and piston failure. Removing bottom spark plugs usually reveals the offending cylinder.
f. Nonmagnetic plating averaging approximately 1/16 inch in diameter; may have copperish tint. Quantity found – 1/4 teaspoonful or more; ground aircraft and investigate.
g. Same as in step b. but may be slightly larger in size and minus copperish tint. On direct drive engines, propeller action may be impaired. Ground aircraft and investigate.
h. Nonmagnetic metal brass or copperish color. Resembles coarse sand in consistency. Quantity of 1/4 teaspoonful or more – ground aircraft and investigate.
i. Anytime metal is found in the amount of 1/2 teaspoonful or more, it is justification for engine removal. Ground aircraft and investigate.
j. If any single or several pieces of magnetic or nonmagnetic metal larger than previously mentioned in steps e. through i. Ground aircraft and investigate.

NOTE
If the origin of the metal contamination cannot be determined, a call may be made to the Lycoming Product Support Department. A good description (photographs, color and quantity, etc.) of the metal may result in placing its origin. When phoning Lycoming or when returning metal removed from engines, supply the complete engine model designation, serial number, history of engine, oil temperature, oil pressures, and any unusual behavior of the engine on the ground or during flight. Do not ship material to Lycoming without first calling the Product Support Department.

 

9. If examination of the oil filter or suction screen, per the above, indicates abnormal aluminum or iron content, contact a technical representative of the Lycoming Product Support Department at 1-800-258-3279.

 

NOTE
Warranty for the metal analysis is available for engines listed under Models Affected only if the engine from which the sample is taken is a new, rebuilt, or overhauled engine from the Lycoming factory.
 

[NotarPilot]

I'd really like to know how many hours Jim has on his engine.

[MooneyBob]

.

[merrja]

Thanks all..... I'll check my log books, but should be ~900 hours and my filter was clean in my last annual in Jan, believe my engine is the A1A.  

[Gone]

See http://mooneyspace.com/topic/15547-metal-in-the-oil-filter/?hl=%2Bmaking+%2Bmetal

Ned Gravel

Lucky steward of C-FSWR, a '65 E model at Rockcliffe, Ontario, (CYRO)

Sent from my iPad using Tapatalk

[The-sky-captain]

Check the suction screen too. That's where the big, scary metal chunks will be.

[DXB]

In addition to detailed Lycoming recommendations cited above, latter portion of this webinar is a great guide on how to triage metal in the filter:

 

http://www.eaavideo.org/video.aspx?v=2149054014001

 

Hopefully the conclusion that you need overhaul is premature?  May be worth sending out to identify source of metal.  Per Mike Busch the content of the filter on visual inspection is often misinterpreted.

[M20F]

Thanks all..... I'll check my log books, but should be ~900 hours and my filter was clean in my last annual in Jan, believe my engine is the A1A.

Check when they last replaced the crank/cam it may have been done 900hrs ago or it may not have. Once the nitride goes on the cam the lobe will wear quick.

[merrja]

UPDATE-  OK, here is where we are

1) #3 & #4 cyls had low compression so we pulled the cyls

2) Metal was coming from the cam and it was pitted

3) cyls were worn so badly by the metal the even the cross hatches had been worn off one cyl

4) engine had 700 hours from a 2005 rebuild...presumably there was some rust on the cam from inactivity after the rebuild?  I bought the plane with 200 hours and  I've flown 600of the 800 hours in the last 3 years

5) All this happened within the last 50 hours as there was no metal in my filter at the last oil change...During these 50 hours I've flown to the Eastern Bahamas and across Lake Michigan!  Yikes

 

I am guessing nothing but a rebuild is in my future......  Any ideas?

Thanks,

Jim

[Raptor05121]

It seems like the first few years of its life of sitting probably helped kill it.

 

[ArtVandelay]

And it sounds like they didn't replace the cylinders when they did the last rebuild. I'd overhaul it and replace all cylinders with new ones, I'd overhaul the prop and mags as well.

[Shadrach]

And it sounds like they didn't replace the cylinders when they did the last rebuild.

theory is based on???

If an engine is run properly and regularly, telling the difference between a 300hr cyl barrel and an 1800hr cyl barrel would be a real challenge.

[M20F]

I am guessing nothing but a rebuild is in my future......  Any ideas

If the cam is making metal it means the nitrate is shot and once that goes it takes about 20-25hrs till the lobe snaps, I would stop flying it. You will need to split the case and replace the cam at miminmum.

This though is where things get tricky as you can chose to do an overhaul which will involve replacing exhaust valves on the cylinders and some other parts, or you can just do a repair and return to service. Depending on the health of the cylinders and whether you intend to sell the plane in the near future just fixing the bottom and reusing the cylinders is a viable and much cheaper route though it sounds in your case that might not be an option.

There is a lot of confusion when it comes to the word overhaul. While the engine was overhauled 800hrs ago my guess is they put in the old or a right at tolerance cam in (or a newer one which hanger talk says they suck and you should find an old good one on a shelf somewhere). Overhaul doesn't mean all new stuff and you really need to read any logbook entry concerning engine overhauls, repair and return to service, cylinders, etc. carefully to see exactly what they did. Given the pattern of the hours flown, time, etc. looks to me like the cam just wore out. The sitting early in life might have been an issue if 20hrs after sitting the issue developed but given the times you listed especially in the last 2yrs, just sounds like it wore out.

[Gone]

Oh.......   This sounds sooooo familiar. 

 

If metal is in the oil, look to overhaul the oil cooler and the prop governor.  I had to replace both this year for the same reason. During their overhauls, both were declared scrap.  

 

Splitting the case and getting a new camshaft apparently includes new lifters too.  No new cylinders for me because we caught it at the very beginning and there was zero scoring in the jugs.  But it was still expensive.  Labour, new cam and lifter kit, overhauled oil cooler and prop governor came near to 11 Canadian AMUs.  Consider two or three more if you have to buy a new governor and oil cooler.  I think we bought the cam/lifter kit from ECI.  I am not certain if Lycoming has solved their QA issue on parts yet.

 

Just be glad you did not also have my 10 year overhaul on the prop that scrapped the blades and forced me to buy my way out of the annual hub AD as well.

 

Good luck.  I really feel for you.  

[ArtVandelay]

theory is based on???

If an engine is run properly and regularly, telling the difference between a 300hr cyl barrel and an 1800hr cyl barrel would be a real challenge.

The fact that the cross hatches were worn off, you saying it would be normal for that to occur in 300 hours!

[AESpecialists]

  As others have pointed out, once the hardened surface of the cam is breached, wear is very rapid. Once that threshold is reached the cam can go in as little as 5hrs of operation, so the last oil change being fine is not really relevant.

  I'm willing to bet the piston skirts have little bits of steel embedded in them, which is typical, and a diagnostic tool of cam failure vs cylinder issues. Even if the decision is made to repair and move on, they will need to be replaced.

 

SB240v outlines mandatory replacement items at overhaul if you want to compare to the logbook entry or 8130.

[Shadrach]

The fact that the cross hatches were worn off, you saying it would be normal for that to occur in 300 hours!

No, I am saying that it's normal for the crosshatch to still be vividly visable on a cylinder barrel with 2000hrs. Piston rings should not come into contact with cylinder barrels unless something is very wrong. Crosshatch should not really wear at all. It is there to hold oil on the cylinder wall.

[bonal]

Two scariest things forced landing and making metal. I wish I could get overhaul insurance.  I think I am going to start an OH savings to go along with my annual savings account.  Need to do what I can to protect my real life savings from this dastardly hobby.  I always wonder what makes addicts continue with their behavior as it ruins there lives I wonder if its the same. Is aviation some sort of twisted self abuse.

Good luck with the work ahead and share any insight you may have on your journey.

[Parker_Woodruff]

That is a shame, especially since you have flown so much.  Unfortunately, 200 hours from 2005 to ~2012 isn't a lot of hours.

[M20F]

Unfortunately, 200 hours from 2005 to ~2012 isn't a lot of hours.

The issue didn't develop in 2012 it developed in 2015 after flying 200hrs a year in the last 3 years (600hrs after it sat). Sitting had nothing to do with the issue, the cam just wore out. This is evidenced by the metal coming off it which only occurs at end of life, you can verify that by getting the cylinder inspected as AES highlights.

No matter how much cam guard we use, how often we change the oil, and how much we love and baby our engines they eventually wear out and need to be overhauled.

[DXB]

UPDATE-  OK, here is where we are

1) #3 & #4 cyls had low compression so we pulled the cyls

2) Metal was coming from the cam and it was pitted

3) cyls were worn so badly by the metal the even the cross hatches had been worn off one cyl

4) engine had 700 hours from a 2005 rebuild...presumably there was some rust on the cam from inactivity after the rebuild?  I bought the plane with 200 hours and  I've flown 600of the 800 hours in the last 3 years

5) All this happened within the last 50 hours as there was no metal in my filter at the last oil change...During these 50 hours I've flown to the Eastern Bahamas and across Lake Michigan!  Yikes

 

I am guessing nothing but a rebuild is in my future......  Any ideas?

Thanks,

Jim

 

Regarding above, I have no real engine expertise, just a sordid history of obsessive Mike Busch webinar watching.  So someone please correct me on my present understanding of the following points if necessary:

 

- Corrosion related pits on cam lobes alone do not explain visible ferrous metal in the filter.

- Extensive pitting can create uneven loads at the cam-lifter interface that slowly wear away the hard exterior of the cam lobe around the pits.  This progresses to spalling of the softer metal inside the lobe, which is the visible ferrous metal in the filter.

- The rough interface also spalls the softer metal of the lifters, which contributes visible metal to the filter.

- On lycomings this is likely to happen on the cam lobes and lifters driving the intake valves because those lobes work twice as much- opening 2 valves per lobe.

- As this cam lobe loses height from spalling, there is a gradual decrease in engine power from incomplete intake valve opening.  

- Though the spalling happens fast once it starts, it does not produce catastrophic engine failure.  So unless someone chooses to ignore obvious, large amounts of ferrous metal in the filter and then also an anemic engine, the only danger from cam/lifter spalling is to one's pocketbook.

 

Again note disclaimer, and folks with real expertise please correct me.  And my sympathies to the poster.  I'm certain the time for my O-360 will come one day too.

[Shadrach]

The issue didn't develop in 2012 it developed in 2015 after flying 200hrs a year in the last 3 years (600hrs after it sat). Sitting had nothing to do with the issue, the cam just wore out. This is evidenced by the metal coming off it which only occurs at end of life, you can verify that by getting the cylinder inspected as AES highlights.

No matter how much cam guard we use, how often we change the oil, and how much we love and baby our engines they eventually wear out and need to be overhauled.

Interesting take. I don't really believe that cams just "wear out". They can rust, the can be damaged by lack of lubrication, they can self destruct due to poor metallurgy and any other number potential issues. However during normal operation, the cam is not "wearing" at all. There is no metal to metal contact during normal operations.

I agree that this likely had nothing to do with lack of use.

[Yetti]

Curious if your missions were long flights with constant power settings.   Also sounds like a switch to Continental since they figured out the valve tappet issue

 

http://precisionengine.home.mindspring.com/engine3.htm

 

Maybe we should be running diesel truck oil.  Does anyone know the source of the lifters for Lycoming

 

http://www.hotrod.com/how-to/engine/flat-tappet-cam-tech/