Did he use a neoprene seal? 1954 235s still used shims on the mains. Some people try to use the later neoprene seal on these engines with limited success as the shims hold the ends of the seals apart, this creates a path for the oil. The seal groove in the block and cap is also deeper so the seal is not held tight to the crank. I would always use a rope seal on these engines.
