Probably used during the manufacturing of the cam cover as a machining
datum/part handling feature. It's not a through-hole so no need to worry
about contamination or spitting oil.

"Chris Driscoll" <ack@sio.midco.net> wrote in message
news:vkjhojb0pj5oc5@corp.supernews.com...
> http://sio.midco.net/relic/ummboltq.jpg
>
> is there supposed to be a bold there? (far left on cylinder head) just
seems a
> little strange to me that there's an open hole to the crankcase?
>