Suzuki 2 Strokes

hello guys, i just bought a basket case T500 and the engine is apart and i noticed a broken bolt hole in the lower case
can anyone tell me what goes in the hole, its not a normal hole all the way through, i attached pics, thanks

thats the drain and crap trap for the main bearing lube feed, looks like those cases have taken a battering at some time, nothing unusual for those to be split from either animals working on them or twatting kerbs etc.

I usually mill the broken section out and weld in a drilled and tapped piece of ally bar to suit

great idea, thank for the info