Originally Posted by Daddy Dan
Someone correct me if I'm wrong here but all oil in these engines passes through the oil filter, right? Now, if you changed the oil and dirt and gunk broke loose, it may have plugged the oil filter and that could cause a large restriction.
filters have a bypass valve, so if they are completely plugged, the oil will bypass the filter and just not be filtered
if a rocker has "fallen off" it will not really affect the oil pressure, you would have one dead cylinder
it sounds to me like you have wasted the main, rod, and/or cam bearings....the pump produces oil flow, restriction to that flow is what creates the pressure, and the bearings are what creates that restriction...if the gap is too large, then there is less restriction and the oil just falls out without building up to any pressure...the pressure raises with RPM because that is also increasing the speed that the oil pump is turning, which means it is now pushing a higher volume of oil, which cant fall out of the gap between the bearings as fast, so it creates some restriction
sounds like your $620 beater needs a new motor, or a rebuild..or you can go the cheap route and just rol some new bearings into it without doing any machine work, or do a crank kit...got several options, anyway