mystery 1641 part??
 

Hello All-
About 2 weeks ago my 1641 snapped an exhaust rod. (Not really sure what caused that, except that the cooling fins were gunked up form oil from the breather tube.)
Anyway, I just replaced the rod and also installed an OHV seal kit on both sides while I had it apart. While doing this I ended up taking all the housing off the engine, as well as moving the firewall out of the way.
I put it all back together last night and didn't have the valves adjusted correctly. So I jumped on YouTube, watched another 4 videos and set those properly this morning.
It started up but was running at a much higher sounding rpm than I was used to, with a higher pitch. I had throttle down low and after a few minutes decided to put it to high. After about 5 seconds on high, this piece of metal shot out of the engine and hit me in chest! I just don't know where it originated from? It came out of the oil filter side near the blower motor housing. Once it shot out, the engine changed rpm and tone. It now sounds normal.
I think the piece ricocheted because I saw a spark right before it came flying out. Is it possible this piece was being "ticked" by the flywheel in the blower housing and somehow was finally spit out? (It has splines on part of the shaft but is not threaded inside as if it was meant to receive a bolt.)
Also strangely, now when I turn it off, it takes a few seconds for the engine to actually turn off. I hope this cub is not on its way out. I use it all year round.
Thanks for any help!
Attachment 110976

Attachment 110977

Never mind. Found it. It's a spacer. Part 668A. Take care!