[Teutonics]

Low oil can definitely be a cause.

I have rebuilt many B&S engines with broken con-rods, and most were due to to low oil (and it's always black and smelly because it was never changed). The worst case would also require replacement of the crankshaft due to bearing failure. If you got lucky, it was just the con-rod that broke, which is a simple repair (assuming it didn't do other internal damage or punch a hole in the case).

The upside is that if it can be repaired (cost effectively), it should be fine.