Curious Evaluation of Oil Chip Detectors

 While enroute to Alaska, after a fresh rebuild with an engine performance upgrade on my Rotax 912UL, I experienced rough engine operation. Subsequent mechanic work at Watson Lake, Yukon Territories attempted to find the source of the rough engine operation. A variety of things were checked; I believe the final conclusion was that a carb cleaning had somehow solved the problem.

One of the things that was checked was the magnetic chip detector, and it looked like this:

Recently, I posted details associated with the accident I subsequently experienced at Lake Hood. If you haven't read it already, it's a must read. It includes references and excerpts from the final NTSB report.

Standard Pilot Blog: Chipper 2 NTSB Final Report Lake Hood Accident N3748 (jameswiebe.blogspot.com)

Also, if you haven't already read it, another engine upgrade to my Rotax failed before this one, in Alabama. You can read it here:

Standard Pilot Blog: The Curious In-Flight Engine Failure of N3748 in Alabama (jameswiebe.blogspot.com)

After I posted recently, a couple of Deep Throat information friends have emerged to give me additional info. One of them provided me with a copy of a page from the Rotax maintenance manual.  Wish I had it handy that day. Here's what it shows:

Well doggone, if that 'non acceptable' picture from Rotax doesn't exactly match my photo.!!

I wish I'd stopped my journey at Watson Lake. The heads could have easily been removed, and it is possible (and I believe likely) that the witness mark on the top of the piston would already have been there from the valve strike. I wouldn't have ended up in Alaska, but I also could have avoided that useless trip to the emergency room.

But that was then. Meanwhile, my experimental aviation journey has taken a new path. I am loving my ULPower 350iS engine and I just did my first oil change on it, on Chipper 2, N318KW:

After removing the chip detector from my ULpower engine, I saw no metal on it.  I smeared the oily residue onto a paper towel, and with the help of an A&P/IA friend, he examined it under a magnifying glass. Absolutely nothing found! Yeah! That's the way it ought to be. Back to flying.