Strange engine bolt. Where does it go?

[flathead4rd]

I'm reassembling my engine 1950 8-CM and I found this bolt that is quite different than the rest. It's a 7/16 hex head about an inch about a quarter long, coarse thread. It has a hole drilled through the center threaded end and another through the top end of the threads. I assume it's used to lubricate some part. I tried to post a picture but no luck. Any thoughts?