farmall pete
Member
Looking for advice. Bought a 656 with a c263 motor. Motor has a knock in it. Motor checks out good otherwise: oil pressure steady 30 psi, does not smoke, all cylinders compression test at around 150 psi dry. Motor runs smooth, just knocks. Set the valves but no change in knock. Tried pulling the plug wires one at a time to isolate the knock; no change. Pulled the oil pan, bearings Ok.
Was thinking it could be a piece of carbon broke loose & is sitting on top of one of the pistons. Maybe wishful thinking on my part as an alternative to a piston pin or skirt slap. Heard of an old remedy: splashing water into the carb intake with motor running to steam clean and maybe break up the piece. Sounds a little risky.
Any other ideas for diagnosing short of pulling the head to take a look see?
Was thinking it could be a piece of carbon broke loose & is sitting on top of one of the pistons. Maybe wishful thinking on my part as an alternative to a piston pin or skirt slap. Heard of an old remedy: splashing water into the carb intake with motor running to steam clean and maybe break up the piece. Sounds a little risky.
Any other ideas for diagnosing short of pulling the head to take a look see?