One day back in 1995 an Aerostar came into our airfield with one turning and one not. There was oil all over the Left wing behind the dead engine. The owner took the cowl off. It turned out that one of the bolts holding a rod on the crankshaft had broken. The rod went up, broke the case just under the fuel distribution manifold, and then slid up the barrel of the cylinder, cutting a nice notch in the cylinder wall, until it got to the fins.
The owner was in a quandary. He'd had both engines overhauled at the same place at the same time. And while there was an Airworthiness Directive out on rod bolt failures for that engine, the one that failed was not of the lot covered by the AD. He had to replace that failed engine but should he replace both of them? He said that he was considering buying two zero time engines, replacing the failed engine, and sticking the other new engine in the back of the airplane in case the Right one did the same thing.