[Dr Chill]

Folks, I'm rebuilding an atomic four that was stored for several years after being partially assembled. I've been following the manual. I have the pistons and crankshaft in, the crankcase oil pan in. As I'm putting the camshaft in, I notice that there's a hole behind the sprocket. It doesn't appear to have been tapped, and it has evidence of being painted. Is there something that needs to go into that hole, or is it there to allow oil to pass from the block over to the transmission housing?