Has anyone ever tried to draw a vacuum from the inlet hole at the oil filter housing?? If there's air trapped inside the pump or the oil lines leading into the engine, it seems this method would evacuate it out. I need to find a rubber plug of some sort to fit snuggly inside the hole and drill into the plug with a fitting so I can attach the vacuum pump inlet line.
I did replace the oil pump with another from a known, running engine so I really don't think its the pump but anything is possible.
I spun the engine over just now but got no oil coming into the filter housing from the pump. I used a pump oil can to push oil through the opening towards the pump but still nothing came out. Dang it. Frustrated with this thing now but its got my time, and my money so I've got to work through this process until its solved. It appears the oil tank is still full so the pump may not be pulling oil out. Odd, I primed the pump and got oil flow before I installed it on the engine. I'm going to pull the incoming oil line fitting off now to see if anything gravity flows out.