The previous owner neglected to inform me that he has either lost the sump bolt or rounded the threads and decided on the best course of action would be to put any old bolt in the hole and metal weld paste around it.
I found this out when doing an oil change.
No the metal weld is starting to weep oil and i thought i may be able to helicoil the hole and fit a new plug as removing the whole sump will require jacking the engine.
So why not just hit up the local parts house for an off the shelf oversized self tapper plug? You already know that it's a BMW diesel. Surely any decent parts house can readily give you a choice of factory, helicoil or oversized.