250 Crank Case Housing Repair

Biggest problem is practice weld on the material. If you don't know the composition of the material, it can go south quick.

Then there is the cleaning it up and filling the surface for a good seal at gasket. Best to make a jig that holds it together and heat the entire case piece, then weld to reduce any warpage that "will" occur.
 
Id JB that sucker. solvent, sandpaper, more solvent. Then torch it lightly, epoxy and bolt it up lightly to the case before it sets. rub excess from the seam and wait. pull it off and remove leftovers with a razor from the mating surface if any. JB'd more than one cracked case cover and it works. Thats an extreme split, but doable. Heck if it doesn't work, you're left with what you have now - $7 for the try.
 
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