1990 740 turbo
Found this cracked and broken housing that supports the pinion shaft on the starter motor.
Wondering if this is a typical break or if it's indicative of other problems.

 

The starter broke, no big deal! No reason to suspect anything more...

 

Very unusual failure. My concern would be if there is some sort of chunk of metal flying around in the bell housing that might have cracked it. From the looks of the pic though, I don't see any nicks on the edge of the broken piece indicating that it was struck by a piece of metal. I can't see the other edge though. If there are no such indications, I would just chalk it up to a defective orignal part.

 

Thanks for the input. When it was still in place I couldn't rotate the engine by hand so I feared seizure (always fearing worst) and that a sudden seizure during cranking might have been enough to crack the support casting. After I removed it I am able to crank the motor by hand so no more seizure fears. I am going with the theory that it was dropped prior to installation and crack was started then.
Thanks again.
Thinking now (worst case again) there may be a tiny fragment of that casting left in the bell housing. I'll now see if I can access the bottom of the flywheel and check, otherwise I'll just get a new starter in and see how it goes.