I’ve just had to rebuild the oil pump on my 1913 2 3/4 hp. I found that the one way valve and spring at the base of the pump is missing, however the valve on the top of the crankcase is in place. My engine has apparently been running for quite a few years in this guise.
I tried to unscrew the ‘lid’ but reckon I’ll break the slotted thread if I try any harder. Given that both one way valves work in the same direction between pump and engine, are two necessary?
