I'm working on a couple of possible solutions to the chronic "low oil pressure" problems of spray-oiler engines. With a little creative plumbing, it looks like the Melling M-45 oil pump intended for the full pressure 235's and 261's can be adapted to the 216's and spray-oiler 235's. The gears in those pumps are taller, and they will move a higher volume of oil. The reason oil pressure gets low, especially in an engine with a lot of miles on it, is the fact that lube oil leaks out of a bearing with extra clearance faster than the pump can replenish it. The gears on the 216 pump are so short that once the main bearings and cam bearings get worn somewhat, the pump just can't keep up with the demand for oil, so the pressure drops.
Another approach would be to adapt the engine for a newer, higher volume pump. I'm working on an adapter that will mount a Melling M-55 pump for a small block V8 to a stovebolt engine. The M-55 has even taller gears than the M-45, but it also would need some machining on the pump housing to fit the adapter properly. I did some research last night and it looks like a pump for a 230/250/292 6 cylinder would be easier to adapt to the earlier sixes. Any of the above pumps should be able to supply 20+ PSI oil to a 216- - - - -AT HOT IDLE! Stay tuned for more developments!
Jerry
