I ended up finding the diagram on a OEM part site 😆
I think the reason it had a crack was becuase he had hired a teenager to work on it, (which i should have saw coming) he must of assembled the parts wrong, sent it on the kick start, and a crack had formed.
Ended up driving it around the park for a good while, with new oil. Runs great, i think the engine is near the end if its life since it tops out at a mear 28mph.
Also, all eletrical works except the headlight, tested the bulb, it's fine, im guessing he hacked up the wiring to get it to work, since there is anfew mystery wires that have been spliced