Found this in my pan during oil change

well obviously none of us know exactly where it came from, however, i can say this beyond a reasonable doubt....

"it's NOT the nut from behind the wheel"!

 

Yes, if it made it back to the LR corner of the head it could easily fall through.

 

ok, i never pulled an engine apart as a driver. i didn't see where it would have been able to squeeze thru an oil drain in the head.

 

That's another thing about selling out this year. I don't have to deal with stuff like this any more.
Hope it's just a Chinese nut off a work bench. Wouldn't be the first time the oil change tech wasn't paying attention.

 

Is that a 1967 quarter?
Notice it doesn't have a Mint mark

 

Looks plated in the last few pics. Don't recall seeing plated hardware in any engines I've ever taken apart.

 

The BXS has separate VVA / Jake housings that utilize 1/2" nuts if I remember correctly. I know a C15 in a Columbia is tight but I would still highly recommend pulling the valve covers and taking a look. I've seen plenty of Chinese hardware used on the internals of engines by techs/shops, so just because it isn't a CAT nut doesn't mean anything. Keep a close ear on it and good luck !

 

BTW, a 1/2" nut has 3/4" hex.