Metal in the filter, diagnostics and corrective action

timwinters

timwinters

Ejection Handle Pulled
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Chapter three:

Sunday's oil change revealed metal in my filter. Presumably bronze though one oil analysis lab told me that aluminum can look like bronze in a filter. Definitely non-ferrous.

They are very small flakes, about 1 mm or less in diameter (comparing it to the diameter of the leads in my old Pentel drafting pencils). With a very few (about 6) larger ones, about double that size.

I'd estimate that the total amount is less than an 1/8 teaspoon...maybe less than that even. There are quite a few flakes but, man, they're small.

Here's today's game plan.

1) Standard oil analysis is going to Blackstone as every oil change does to see what they find.

2) The filter pleats are going to Aviation Laboratories in LA/TX. They say they can perform metallurgy tests on the flakes and determine exactly which engine component tossed them out...I'm skeptical...we'll see about that.

3) While we're waiting for #1 & #2 to be accomplished, I will pull the rocker covers and see if one has flakes or something is obviously amiss...hopefully I will find something (rocker bushings or valve guides will be a lot cheaper than main bearings).

Oh, and BTW, yesterday I filtered the oil through a paint filter (and I repeatedly stirred the oil during the pouring process in an attempt to suspend any solids that may have settled out). There was little or nothing in the oil. I haven't had a chance to speak with the A&P about this yet but I certainly hope that's a "good news" item.

(productive) Suggestions and commentary welcome.
 
timwinters said:
Chapter three:

Oh, and BTW, yesterday I filtered the oil through a paint filter (and I repeatedly stirred the oil during the pouring process in an attempt to suspend any solids that may have settled out). There was little or nothing in the oil. I haven't had a chance to speak with the A&P about this yet but I certainly hope that's a "good news" item.

(productive) Suggestions and commentary welcome.
Click to expand...

The clean paint filter means is that the oil filter was doing its job which is good news in a way but doesn't address much about the health of the engine.
 
Tim, I don't have any ideas to offer you. From my neophyte point of view though it sounds like you have a good plan. As a hope to be soon owner, I do hope you follow up on this as you get info, it could be very helpful to folks like me who don't really know anything.
 
Tim, your post has raised an interesting question for me. If the filter works as its supposed to what is the purpose of the oil analysis, since all the metal will be accumulated in the filter and not in the oil that is drained? Unless of course the amount of microscopic pieces in the oil can tell you the same thing that is in the filter.

Although the flakes on the filter were apparently non ferrous did you run a magnet through the oil?
 
What were you seeing on prior oil analysis?
 
I like pie(my standard thread marking method).

The filter doesn't pick up everything. particulate matter smaller than the media size gets through, and also there's a bypass on all filter installation that sometimes lets unfiltered oil through when cold, or if there's a pressure surge, or if the filter becomes clogged.

Waiting to see where this goes.
 
AggieMike88 said:
What were you seeing on prior oil analysis?
Click to expand...

They've been impeccable w/ consistently lower than average wear metals & contaminants across the board and accompanied by a "this engine is doing great" oratory.

I'll be interested to see what Blackstone finds this time...if nothing...I may change my mind about oil analysis...I've been a strong proponent until now.
 
AdamZ said:
Tim, your post has raised an interesting question for me. If the filter works as its supposed to what is the purpose of the oil analysis, since all the metal will be accumulated in the filter and not in the oil that is drained? Unless of course the amount of microscopic pieces in the oil can tell you the same thing that is in the filter.

Although the flakes on the filter were apparently non ferrous did you run a magnet through the oil?
Click to expand...

In some cases an oil analysis can come back ok but the filter tells another story.

Personally, I've always felt that a good filter inspection is adequate in catching problems quick enough to remedy them before a catastrophic failure occurs. I don't know anyone who has actually taken an engine apart based on an oil sample, everyone waited until the problem got worse because they were hoping the bad oil sample was a one time deal.

Tim, your approach to diagnosis sounds reasonable. I'm interested to hear what you find.
 
timwinters said:
They've been impeccable w/ consistently lower than average wear metals & contaminants across the board and accompanied by a "this engine is doing great" oratory.

I'll be interested to see what Blackstone finds this time...if nothing...I may change my mind about oil analysis...I've been a strong proponent until now.
Click to expand...

Filter inspection and oil analysis are complimentary, sometimes there is an overlap in findings, sometimes not, which can actually help in diagnostics of what is failing.
 
Just wanted to say with all the talk about bad threads and posters, etc, this thread (and the one before this on the same subject) is exactly why I come to POA.

As a fellow 182 owner I like to learn as much as I can about the O-470.

I have learned a ton already and looking forward to seeing the resolution. Keep the good info coming!
 
Adam,

I missed your post this morning, sorry. But I think others have answered as I would have...especially docmirror...
 
AggieMike88 said:
What were you seeing on prior oil analysis?
Click to expand...

Mike, now that I'm in front of a real computer instead of my iPad...attached is my latest oil analysis...about 35 hours ago...
 

Attachments

  • N5057D-060415.pdf
    22.1 KB · Views: 66
what that sez to me is that your metal wear is not measurable.....it doesn't say there isn't wear, just not small particulate sized wear.

Be sure and check the sump screen too....:nono:

Based on your symptoms.....I be betting on valve guide wear. :yes:
 
neilw2 said:
Just wanted to say with all the talk about bad threads and posters, etc, this thread (and the one before this on the same subject) is exactly why I come to POA.

As a fellow 182 owner I like to learn as much as I can about the O-470.

I have learned a ton already and looking forward to seeing the resolution. Keep the good info coming!
Click to expand...

I'm quite confident that you're looking forward to seeing the resolution far more than I'm looking forward to paying for it! :)
 
Any ideas on what is causing the high calcium levels? Almost 5x the universal averages.

You been feeding that beast milk?
 
timwinters said:
Chapter three:

Sunday's oil change revealed metal in my filter. Presumably bronze though one oil analysis lab told me that aluminum can look like bronze in a filter. Definitely non-ferrous.

They are very small flakes, about 1 mm or less in diameter (comparing it to the diameter of the leads in my old Pentel drafting pencils). With a very few (about 6) larger ones, about double that size.

I'd estimate that the total amount is less than an 1/8 teaspoon...maybe less than that even. There are quite a few flakes but, man, they're small.

Here's today's game plan.

1) Standard oil analysis is going to Blackstone as every oil change does to see what they find.

2) The filter pleats are going to Aviation Laboratories in LA/TX. They say they can perform metallurgy tests on the flakes and determine exactly which engine component tossed them out...I'm skeptical...we'll see about that.

3) While we're waiting for #1 & #2 to be accomplished, I will pull the rocker covers and see if one has flakes or something is obviously amiss...hopefully I will find something (rocker bushings or valve guides will be a lot cheaper than main bearings).

Oh, and BTW, yesterday I filtered the oil through a paint filter (and I repeatedly stirred the oil during the pouring process in an attempt to suspend any solids that may have settled out). There was little or nothing in the oil. I haven't had a chance to speak with the A&P about this yet but I certainly hope that's a "good news" item.

(productive) Suggestions and commentary welcome.
Click to expand...

That equals .040 = .080 flakes....:eek:..


I agree. removing the rocker covers might disclose the defect.... Hopefully it is just rocker bushings.... :idea:
 
When metal shows in the filter suddenly between oil changes, some thing happened during that time period.

We gathered from the other thread that we have a sticking valve. IMHO that valve has already struck the piston deforming the top land of the piston. which in turn has rubbed the cylinder wall producing this metal debris in the oil.

I would borescope all cylinders trying to see which piston head shows a mark.

Any metal produced this way will go directly to the filter IF I say IF it gets picked up by oil flow.

I would do this, buy 5 gallons of stoddard solvent, pour it thru this engine, catching it with a white rag stretched over the head of a 5 gallon bucket. and see what comes out of the oil pan.
If you get any aluminum in that catch. I can Guarantee you have a deformed piston. Which in most cases will start galling the wall to cylinder and result in a catastrophic failure.
 
Thanks, Tom.

One question...do we know for sure that a low compression O-470L is a non-clearance engine?
 
Hmm. I just learned that Cam Guard is made of breast milk.


Sent from my HTC6525LVW using Tapatalk
 
Should I be taking away from this that the filter check is more helpful or telling than an oil analysis?
 
AdamZ said:
Should I be taking away from this that the filter check is more helpful or telling than an oil analysis?
Click to expand...

No, not at all. It all depends on the failure mode of the parts making the metal.....and the "size" of metal it makes (large, medium, or small).

Fine metal measured in PPM is indicated nicely with oil analysis. Medium to large flakes or chunks of metal will not indicate in the oil analysis but, will show in the filter and sump screens.
 
AdamZ said:
Should I be taking away from this that the filter check is more helpful or telling than an oil analysis?
Click to expand...

IMHO, need to do both, plus compression test, plus boroscope inspection to keep tabs on the health of your engine.
 
timwinters said:
Thanks, Tom.

One question...do we know for sure that a low compression O-470L is a non-clearance engine?
Click to expand...

What is that?

Do you mean the valve lifter is a zero lash lifter? (Hydraulic)
 
Tom-D said:
What is that?

Do you mean the valve lifter is a zero lash lifter? (Hydraulic)
Click to expand...

He's meaning interference or non-interference. In other words, will the piston hit the valve?

I know the E series Continentals are, not sure on the 470s. I assume so though.
 
N801BH said:
That equals .040 = .080 flakes....:eek:..


I agree. removing the rocker covers might disclose the defect.... Hopefully it is just rocker bushings.... :idea:
Click to expand...

You know...I looked at the small portion of filter pleat that I kept again today. And I was grossly exaggerating on the size of the particles. They are a 1/4 to a 1/3 the size of what I originally estimated.


mondtster said:
He's meaning interference or non-interference. In other words, will the piston hit the valve?

I know the E series Continentals are, not sure on the 470s. I assume so though.
Click to expand...

Exactly, I would be surprised if the old low compression engines are interference.
 
timwinters said:
You know...I looked at the small portion of filter pleat that I kept again today. And I was grossly exaggerating on the size of the particles. They are a 1/4 to a 1/3 the size of what I originally estimated.





Exactly, I would be surprised if the old low compression engines are interference.
Click to expand...

Tim....

That is great news...... smaller flakes can easily be accounted for...
 
timwinters said:
Y
Exactly, I would be surprised if the old low compression engines are interference.
Click to expand...

When the valve is stuck wide open, the piston will hit.

Let's say that the valve is open half way, as you crank, won't the valve be pushed to the full open position? Will it retract after that?

With the 0-470, when the engine is hot the guides are large enough to allow free movement, but when the valve guide is allowed to cool, it will shrink around the valve stem. and stop any movement.
When this happens when the valve is closed, you suffer the bent push rod or cracked rocker shaft boss. When this happens when the valve is open it simply stays open until the cylinder heats up enough to allow the valve to operate.
Leave it wide open, it will hit the piston.
 
I have seen aluminum in the oil filter turn out to be one of the wrist pin plugs disintigrating. But it could be some other aluminum piece. Just a one off... How many potential aluminum pieces are there that could end up in the oil filter? I dont know
 
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coloradobluesky said:
I have seen aluminum in the oil filter turn out to be one of the wrist pin plugs disintigrating. But it could be some other aluminum piece. Just a one off... How many potential aluminum pieces are there that could end up in the oil filter? I dont know
Click to expand...

I had that happen on a Lycoming 0-320. Found Al dust/sand in the filter pleats. No mental in the screen. Could not see anything when boroscoping the cylinders, so started to pull cylinders. Took until the 4th to find the hatted pin plug. The pin was scrubbing against the side of the cylinder wall. Not sure what causes the pin to shift to the point it would scrub? :dunno:
 
I've seen that too. Made minor metal for a long time on a C-150. What happens if it is ignored?
 
Rcmutz said:
IMHO, need to do both, plus compression test, plus boroscope inspection to keep tabs on the health of your engine.
Click to expand...

So I get the filter look see and the oil analysis on each change. Are you suggesting a boroscope and compression at each change as well or just upon annual or finding something?
 
Get a $40 USB dental camera.....yes, do a borescope every time the plugs come out. Much more meaningful than a compression check IMHO. :yes:
 
Checkout_my_Six said:
Get a $40 USB dental camera.....yes, do a borescope every time the plugs come out. Much more meaningful than a compression check IMHO. :yes:
Click to expand...
Can you recommend one?

I got a cheap one, tried to use it and the little lense fell off into the cylinder.
I'm sure they are getting better and cheaper.
 
Checkout_my_Six said:
Get a $40 USB dental camera.....yes, do a borescope every time the plugs come out. Much more meaningful than a compression check IMHO. :yes:
Click to expand...

Show me a definitive description of what you are supposed to see.

OK let's say you see some discoloration of a valve, are you going to allow me to pull the Cylinder and send it out for repair?
 
Bill Watson said:
Can you recommend one?

I got a cheap one, tried to use it and the little lense fell off into the cylinder.
I'm sure they are getting better and cheaper.
Click to expand...

I've bought several....any of the cheap ones on E-bay are fine. Do a search on "usb dental camera".
 
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