KZ440 - Little chunk of the block missing.

Looking over the non-runner I just bought, I noticed a small chunk broken off the top of the motor, under the metal cover... Which I think is where the starter is?  The wire from the oil pressure switch runs through a grommet and under that cover.  This is on the right side of the bike.

1)  If I leave it as-is, will anything leak out?
2)  If it needs to be repaired, can I just weld on it a little bit and file it back down?

#1 Nothing will leak out, only water and debris can flow into the starter housing and then drain over the lower case to the ground.
#2 You can mask the area and fill it with JB Weld to close the gap and later touch up with some silver paint.