Babbit is simply a soft bearing material that's bonded to the big end of the rods instead of having a removable bearing. While it can't rust, the rest of the rod can. It's much more likely that the rings and/or the cast iron pistons have rust-bonded to the cylinder walls. Soak the cylinders with KROIL or some other penetrating oil, then carefully pry on the flywheel teeth with a pry bar like the chisel end of a long shepherd's crook wrecking bar. It might be necessary to remove the cylinder head and pound on the piston tops with a block of hardwood and a BFH to break them loose.
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
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