I was wondering exactly which parts are generaly NOT replaced in an
engine overhaul. Assume all new cylinders/pistons/rings/pushrods. I
know that the crank is often not replaced if it checks to spec, and
the cam may be reground and replaced but what about other parts? Are
the con rods usually replaced or reconditioned like the crank/cam?

'From: Jerry Jesion


Cylinders, pistons and pushrods do not necessarily need to be replaced at
overhaul. Theoretically you can overhaul an engine in which every non
consumable part meets overhaul specifications and is reused leaving only
consumable items like piston rings, seals, gaskets, o'rings and hardware to be
replaced.

Connecting rods are not typically replaced at overhaul unless it is required by
service bulletin, AD or they do not meet some specification. I recently sent
out an engine for a repair and the shop found the connecting rods out of
specification due to a change in the overhaul manual from almost 20 years ago.
The engines had been overhauled just 4 years ago.

John Dupre