Test BillBoost

AIR pump?

Okay Bill. I'm swapping my engine, and in the process moving a variety of parts from one engine to another. I thought it was all going great... Then I spotted this bolt laying on the counter, and have NO idea where he came from. Any suggestions? :)

Razorblade for scale. http://www.flickr.com/photos/65736006@N08/5978685002/