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Oil Sump Suction Screen

gharding

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Is it important to check the oil sump suction screen at each oil change? If so, why? Obviously inspection of the oil filter element along with oil analysis is prudent, but curious if most are also inspecting the oil sump suction screen.

Thanks,
Gary
 
Is it important to check the oil sump suction screen at each oil change? If so, why? Obviously inspection of the oil filter element along with oil analysis is prudent, but curious if most are also inspecting the oil sump suction screen.

Thanks,
Gary

Normally accomplished at annual/100hr inspection.
 
Maybe I’m a weird one, but I pull the sump screen at every oil change; it’s easy access (RV-8) and only costs a few cents for a new crush washer. I haven’t found any big metal chunks, but there’s usually a bit of carbon in there.
 
I had read that it was recommended at each oil change, but was curious what others were doing. Thanks for your input.
 
The good news

The good news is that with the size of the holes in that screen, anything you may find in there should have a part number on it!:D
 
Oil Screen

The old guys used to say that if your engine began to make big chunks of metal the screen would protect the oil pump from being destroyed immediately and it might run long enough to get to a airport.

Don Broussard
RV9 Rebuild in Progress
57 Pacer
 
Yea, I guess if you find parts of an oil spray nozzle and helicoil in the screen, probably good to know sooner than later.
 
I check it every 25 hours when I do my oil change. I relish any opportunity to see how the engine is doing.
 
I had read that it was recommended at each oil change, but was curious what others were doing. Thanks for your input.

Do it more often if you like, From the Lycoming manual:

b. Oil Suction and Oil Pressure Screens – At each 100-hour inspection remove suction screen. Inspect for metal particles; clean and reinstall. Inspect and clean pressure screen every 25 hours
 
Readers of my posts are going to start calling me a broken record because whenever I see this kind of question I want to scream READ MIKE BUSCH ON ENGINES.

Because I had so many of these sorts of questions and that book answered them so much more thoroughly than most Q&As on this forum could. For example do you want to know why the screen should be checked, and what does metal there mean versus metal in the filter versus some trend in your oil analysis? And under what kinds of conditions would you want to check it more often than the recommended interval? Just so much good info for people who want to really know how to operate and maintain these things, I've had my plane for more than 20 years and I wish I had this book a long time ago.
 
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Reading Mike’s book is what prompted me to start this thread. Makes perfect sense to me. Just wanted to hear your thoughts. Thanks
 
I check it every 25 hours when I do my oil change. I relish any opportunity to see how the engine is doing.

If you haven't yet, carefully stick your borescope down the oil filler opening both with and without oil in the sump - very interesting. You can also go up the oil drain and inside the suction screen opening after draining the oil.

Depending on which borescope you have, take care to not get it "wet". Most seem to not like that.
 
Readers of my posts are going to start calling me a broken record because whenever I see this kind of question I want to scream READ MIKE BUSCH ON ENGINES.

Because I had so many of these sorts of questions and that book answered them so much more thoroughly than most Q&As on this forum could. For example do you want to know why the screen should be checked, and what does metal there mean versus metal in the filter versus some trend in your oil analysis? And under what kinds of conditions would you want to check it more often than the recommended interval? Just so much good info for people who want to really know how to operate and maintain these things, I've had my plane for more than 20 years and I wish I had this book a long time ago.

Sounds more like an advertisement for MB than anything else.
Lycoming offers maintenance publications for free.
 
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but...

Sounds more like an advertisement for MB than anything else.
Lycoming offers maintenance publications for free.

Would you make the same statement if The Aeroelectric Connection book was recommended?

Or maybe the Bingelis series of books?

Just curious...
 
Would you make the same statement if The Aeroelectric Connection book was recommended?

Or maybe the Bingelis series of books?

Just curious...

Yes if I knew of a source of free material that offered the requested information that the OP was seeking (sump screen servicing)

Of course, the Aeroelectric/Bingelis stuff covers a much wider range of topics, so it's not really apples to apples comparison.
 
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What I enjoy in books like Bingelis, Nuckolls, and Busch is that they take a lot of the information that's "out there" and pull it together into a more accessible format.

One example is the oil suction screen - Busch talks about this in his book "Engines" in the "Oil Analysis" chapter, right up front. Even includes pictures. This is a huge help to someone like me that's still learning how to maintain my aircraft.

I also have John Schwaner's "Sky Ranch Engineering Manual", Second Edition, Operation/Failure/Repair, Piston Aircraft Engines, 1990/1991, and while it is chock full of interesting information, and I really enjoy reading and re-reading it, I can't find any mention of this screen. Of course, I could have missed it, and to be fair, John says many times "read the engine manufacturer's documents, and do what they say."
 
Reading Mike’s book is what prompted me to start this thread. Makes perfect sense to me. Just wanted to hear your thoughts. Thanks
Good to know and I hope I don't sound preachy but I just got so much value from that book which is a lot if good info in one place.

Sounds more like an advertisement for MB than anything else.
Lycoming offers maintenance publications for free.
But not nearly as readable. I'm not affiliated with MB, just a satisfied customer.
 
Is it important to check the oil sump suction screen at each oil change? If so, why?

Lycoming SB480, Table 1, entry two, calls for oil change, filter replacement, and sump screen cleaning/inspection every 50 hours.

That's what I do.
 
Question for Walt?

Now that the OP's question has been answered, perhaps a bit of thread drift will be tolerated.
How many times in your long career have you found anything of consequence in that oil screen?
Thousands of oil changes I assume and what if anything have you ever found that led to an engine tear down or other significant maintenance issues?
Just curious.
 
Now that the OP's question has been answered, perhaps a bit of thread drift will be tolerated.
How many times in your long career have you found anything of consequence in that oil screen?
Thousands of oil changes I assume and what if anything have you ever found that led to an engine tear down or other significant maintenance issues?
Just curious.

Only one time did I remove the screen and with it out came literally a handful of broken pieces. Large chunks. Sent to Lycoming for evaluation and they quickly determined they were lifter bodies. During OH found bad cam and multiple broken bodies, filter was clean. Engine was still running fine :eek:

Have found many screens partially plugged with debris, they likely hadn’t been removed and cleaned in a long time or ever.
 
Have found many screens partially plugged with debris, they likely hadn’t been removed and cleaned in a long time or ever.

Yep, that’s why I check it regularly; while I’ve never found anything notable in the sump screen, it keeps it clean.

Background on why I do it; I bought my engine used (1660 hrs from a flight school Geronimo Apache) and had it field overhauled. The mechanic reassembling the engine mentioned that before bolting the sump back on, he checked the screen and found that it apparently had been neglected for several years... it was pretty well blocked with sludge and gunk.
 
Lycoming SB480, Table 1, entry two, calls for oil change, filter replacement, and sump screen cleaning/inspection every 50 hours.

That's what I do.

But doesn't that same SB in entry five call for oil suction screen cleaning/inspection every 25 hours or four months whichever comes first?

Do you also do this?
 
Pressure Screen

But doesn't that same SB in entry five call for oil suction screen cleaning/inspection every 25 hours or four months whichever comes first?

Do you also do this?

The fifth item in table 1 is for cleaning the pressure screen which is applicable to engines that aren’t equipped with oil filters.

Skylor
 
Oil Screen Saves!

--- over the years I have found a number of things successfully strained from the oil by that little screen. Because it is there, and relatively easy to access, I use it as an indicator of engine well-being at each oil change. I have found chunks of lifter bodies, snap rings, a gear tooth, broken valve lash cap, washers and a snapped off bolt head from the accessory case. Any of these, had they gone through the oil pump would have destroyed it, and most likely have been followed by an engine failure. almost without exception we find large chunks of very hard carbon generated by the antiquated piston and piston ring assemblies. The screen also seems to catch the little half-moon shaped pieces of aluminum shed by the piston pin buttons indicating a soon to be problem related to rod alignment. Those alone most likely wouldn't take out the oil pump, and the oil filter would catch them, but they also will not do any good as they pass through. I see people overlooking this resource for information that could potentially save their lives, then they tie wire an oil filter and a pipe thread drain plug that not only is extremely difficult to remove on purpose but has never fallen off or out by themselves. Wow! go figure. Thanks, Allan--:D
 
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Better look closer

The fifth item in table 1 is for cleaning the pressure screen which is applicable to engines that aren’t equipped with oil filters.

Skylor

I suggest you look again. SB480F, page 2, table 1, left column, 2nd item from the top, at the bottom of that item

"On oil sump - Oil suction screen cleaning/inspection"

In the right column, it shows to be done every 50 hours or 4 months, whichever comes first.
 
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