Hypothetically speaking, how long until . . .

How long would a paper shop towel survive in the oil pan?

  • Less than an hour

    Votes: 7 36.8%

  • Less than 20 hours

    Votes: 4 21.1%

  • Until the next tear down

    Votes: 8 42.1%
  • Total voters
    19
  • Poll closed .
Blatham489

Blatham489

Pre-takeoff checklist
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Latham
Let’s say a plane goes in for maintenance or repair. Somehow, one of those blue paper/cloth hybrid type shop towels ends up in the oil pan. How long is it likely to stay down there before something bad happens - plugged passages, covered sump inlet, getting shredded, etc., and then the obvious carnage that results from same?

Engine is an IO-520
 
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I don't know, but back when I worked in a truck stop one guy left a red rag in the intake, and by the time the truck got to the end of the street there was little pieces of smoking red rag shooting out the stack....

And actually all it did was sputter for a few seconds, then cleared up and ran just fine.
 
Ah. So this is what you intended to post anonymously.

:)
 
The answer to this is determined by which engine.
The oil sump on a Lycoming is not a part of the rotating groups, it is well screened for oil pic up, So the towel should stay there for a long time.
O-200 same thing. but the 0-300 the oil sump is part of the case and very close to the spinning crank cam and other moving parts.
 
Blatham489 said:
Let’s say a plane goes in for maintenance or repair. Somehow, one of those blue paper/cloth hybrid type shop towels ends up in the oil pan. How long is it likely to stay down there before something bad happens - plugged passages, covered sump inlet, getting shredded, etc., and then the obvious carnage that results from same?
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Aren't we happy shop towels don't have owners names on them.
 
Exactly how to you get a towel in the sump of an assembled engine without intentionally pushing the towel through the filler?
 
Clip4 said:
Exactly how to you get a towel in the sump of an assembled engine without intentionally pushing the towel through the filler?
Click to expand...

Some accessories, when removed, leave a large hole in the crankcase. That needs covering while waiting for the accessory to be rebuilt.
 
Why? You mean you are planning on flying until you get to the “best guess” from POA on how long it has? Or else if it is flown, and goes over figure that the rag wasn’t left in there?
 
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We had a mechanic leave a red cloth shop rag in a Honda automatic transmission during a rebuild. It clogged the pump intake, and wasted the new clutch packs, in about 20 miles. I'd be pulling every cover I could off of that engine.
 
Bought a Piper Clipper (Lyc 0-235) near KC one time, flew it home to DSM, and while I was getting my insurance check-out the engine quit (another story). We found a red shop rag in the engine when we tore it apart. Point being, it could be awhile....

Jim

PS- If you're ever getting checked out by a CFI in a different airplane and the engine quits...two words to know. "Your airplane" :)
 
I'm aware of an IO-470 that had a blue towel act as a "magneto hole cover" while the mag was out for overhaul. The towel was overlooked on reassembly and fell into the accessory gears.

A blue towel in the accessory case of an IO470 will take about 3 flight hours before it grenades the engine, in that instance. The gears dutifully shredded the towel and everything got plugged. It was a starved main bearing that got the motor.

In an IO-520, though... a paper towel in the sump... this sump:

esBPrUj.png


How would a square, oil-soaked (thus, heavy) towel accidentally position itself to completely envelop that inverted sump screen and block it?

I can see reduced oil pressure and extra filtration from the additional paper :D but it's easier for me to imagine a towel found in the bottom of the sump at overhaul and laughed about.
 
schmookeeg said:
How would a square, oil-soaked (thus, heavy) towel accidentally position itself to completely envelop that inverted sump screen and block it?

I can see reduced oil pressure and extra filtration from the additional paper :D but it's easier for me to imagine a towel found in the bottom of the sump at overhaul and laughed about.
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I would hazard a guess that the flow of oil toward the pickup would take the paper towel (with its very large surface ares) along with it, covering the pickup screen. Saturate a paper towel in used crankcase oil and imagine how much oil is going to pass through it under moderate suction. I suspect the oil pressure would drop enough to grenade the engine pretty quickly when that happened.

On the bright side, once the engine quits the paper towel will probably sink back to the bottom of the oil pan.
 
covering a 4" round screen completely? Eh, maybe.. I imagine the towel would be pulled in the direction of the screen, and held on that side by suction, not necessarily wrapping and enveloping the screen completely. At least not instantly.

I wonder how much oil pressure can pass through a paper towel? Those oil filter pleats seem sturdier than a blue towel, but of course, oil filters have that nifty bypass.

Either way, OP's (apparently months ago :D ) question regarding the towel getting shredded and plugging oil passages, I think there is zero chance. It's just a question of how much the sump screen got covered, how much oil pressure remained, and how long is reasonable for a pilot to notice this serious lack of OilP and take measures prior to damage occurring.
 
When I was in A&P school, one of our instructors purchased a used Cessna 182. When he changed the oil, he found a cloth shop rag under the oil filter. It had been there for about 40 hours..no symptoms of a problem existed as far as I recall.
 
Take off the quick connect oil drain.

drain oil

Borescope camera inside oil pan.

That is all I got
 
Blatham489 said:
Let’s say a plane goes in for maintenance or repair. Somehow, one of those blue paper/cloth hybrid type shop towels ends up in the oil pan. How long is it likely to stay down there before something bad happens - plugged passages, covered sump inlet, getting shredded, etc., and then the obvious carnage that results from same?

Engine is an IO-520
Click to expand...

So.... how long did the engine last.??
 
Gross. I'm amazed the blue towel turned to muck like that, those things are pretty tough. :eek:

Since I'm eating my words on my hypothesis, any idea how long that thing was in there?
 
I have no input or suggestions, just a side story.

I washed a pair of jeans or hoodie recently with an oily blue shop towel in a pocket. I was amazed that it came out of the dryer in one piece and relatively clean! It had shrunk to about 2/3 of the original size but was still quite usable...so I did!

I almost took a picture and posted it here but didn't get around to it.
 
timwinters said:
I have no input or suggestions, just a side story.

I washed a pair of jeans or hoodie recently with an oily blue shop towel in a pocket. I was amazed that it came out of the dryer in one piece and relatively clean! It had shrunk to about 2/3 of the original size but was still quite usable...so I did!

I almost took a picture and posted it here but didn't get around to it.
Click to expand...

Thanks though! I’m a cheapskate maybe I’ll start washing em!
 
Correct, 5 mins flight time. I did a slightly longer and more thorough run up since it was first flight post-maintenance. All looked good, The failure happened quickly. I was at low power (from memory 12-15” MAP) heard the engine start to get loud, looked at the gauges, next thing I knew (maybe 2-3 secs) it got very loud and lots of vibration, puff of smoke from under the cowl (no doubt as the holes got punched in the crankcase), then I knew I was about to have a bad day. Plane was a total loss, I walked away without a scratch.
 
Blatham489 said:
Correct, 5 mins flight time. I did a slightly longer and more thorough run up since it was first flight post-maintenance. All looked good, The failure happened quickly. I was at low power (from memory 12-15” MAP) heard the engine start to get loud, looked at the gauges, next thing I knew (maybe 2-3 secs) it got very loud and lots of vibration, puff of smoke from under the cowl (no doubt as the holes got punched in the crankcase), then I knew I was about to have a bad day. Plane was a total loss, I walked away without a scratch.
Click to expand...

I like the bold part.

Yikes.
 
Insurance covered the stated amount. We're "discussing" the balance of the remaining value with the shop currently. I'll try to remember to post an update when a judgment is made, probably this year.
 
Note the professional descriptive captions on the photos. They almost look like the type you would find on plaintiffs exhibits.

;)

:D :D
 
Just some further anecdotal evidence as to the ruggedness and durability of those blue paper shop towels...

When this whole mask-wearing thing became a public necessity almost two months ago, I made a mask out of a blue shop towel, a paper clip, and two rubber bands as suggested by our local news website. It worked so well (better than a cotton cloth or other woven material) that I figured I'd just make a new one every day or two rather than go through the hassle of fighting hoarders trying to buy one. After wearing it, I spray it until it's soaking wet w/ some very serious sanitizer I use in homebrewing. Still haven't had to make a second mask... Seven weeks later.

Would NOT want one in an engine.
 
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