Small Engines (Lawn Mowers, etc.): contaminated oil, pencil lead, steel engine


Question
QUESTION: I have a Kawasaki E/no PA540A040705, 535cc. I recently changed the oil, and found tiny flakes of aluminum in the used oil.Any ideas on what to look for first, where might they have come from? It is on a JD 525 MOWER,SER. NO MOF525A-170839. Thanks for your time& service.

ANSWER: Was the oil a silvery color or was there just the small pieces?  What size pieces were they?  How often has the engine been serviced and about how many hours does it have.

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QUESTION: NO. The oil was normal color, black,There was only small specks left on the bottom of the drain pan after I poured the used oil off, to recycle.They were about the size of a pencil lead, or a little larger, they would not stick to a magnet, so they were not steel.Engine has 365 hours, I change oil twice a summer.

Answer
That's a tough one.  We rebuild these engines around 500 hours for a couple of our commercial cutters.  My first instinct is that it's probably not a problem.  But it also could be something beginning to fail, such as where the cam rides in the block.  I don't know that I would say a rebuild is called for, but I would probably change my oil every 5-10 hours for the next 30 hours or so and monitor it closely.  I suspect they'll clear up, but it would be worth 20-30 dollars in oil changes to be sure.