OK- - - -not quite as dire a circumstance! 216's routinely run very low oil pressure, even at cruise speed. Connecting rod clearance will have no effect on oil pressure, as the rods are lubed by spray nozzles in the oil pan. Main bearing and cam bearing clearance will have a big influence on a 216. Where is the pressure gauge line attached to the engine? The only place to get an accurate reading is at the oil gallery on the lower driver's side behind the exhaust pipe. 15-20 PSI at hot cruise speed isn't ideal, but it's not uncommon. Pressure will drop to nearly zero at hot idle, which is also normal for a 216. Don't run water-thin oils such as 5W-30, etc. The engines were designed to run straight 20 or 30 weight. 15W-40 Diesel rated oil will work well. Lots of stovebolters run that oil with no problems.
Jerry
