40c cylinder head questions

[Swawpy]

Ive got a few qustions after removing cyl head on my 40c. First there is a 1 1/4" expansion plug set into cyl head (parts book #46). My question is that mine has about a 5/8" hole drilled in the center of this and I just wanted to verify if this is correct or not? The parts book lists a plug and mine being drilled obviously isnt a plug. Im just assuming this not correct and that someone before me drilled a hole through that expansion plug to aid cooling, or maybe warm-up, or ??? Any ideas?

Also the head is cracked at both the front and rear of head between the oblong and round coolant ports, (from the oblong port towards the spark plug side of head to the round jacket hole. This is just about on the center-line of head. Hopefully some of this description will make sense to somebody. Thanks for any help.[/img]

[Swawpy]

[Lavoy]

The plug is correct.
I would think that as long as the crack do not go to an edge, or are not from water to oil, you should be fine. I know I had one block crack like that, never had a problem with it.
Lavoy

[Swawpy]

Thanks Lavoy, I think Ill just clean the head up and grind the valves and see what happens with lots of coppercoat.