Stovebolt connecting rods are long, and relatively flimsy. It's possible to twist one by simply torquing the wrist pin pinch bolt incorrectly. You might have bent or twisted a rod instead of hammering the Babbit out, but all it takes is a couple of thousandths of extra clearance to make a Babbit rod noisy. A twisted rod makes the piston rotate in the bore as it moves up and down, and causes an oddball piston slap noise.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!