Motorcycle Repair: welding case near oil pump 82 shovel, oil pump, tool shop

Question
Buddy of mine discovered crack in case by oil pump
on his 82 fxr sturgis. Obviously wants to keep numbers matching so we will have to repair. First
are the cases aluminum or magnesium and second is there anything special to watch for during this weld (it is being done in a tool shop but not one
overly familiar with bikes)

Thanks
MWE

Answer
the cases are aluminum. If the shop has never welded cases, you should find sombody that has.
First,with aluminum, the area has to be really clean. Aluminum is porus and there will be some oil in the case.
Second, you need to cut a groove in the crack on both sidss and then weld. Just welding the crack might not hold.
Good luck and happy riding
Mike