Quote: Its not the oil viscosity . Oil weight, or viscosity, refers to how thick or thin the oil is. The temperature requirements set for oil by the Society of Automotive Engineers (SAE) is 0 degrees F (low) and 210 degrees F (high). The oil will be stable to the high limit operating zone .Are you suggesting the oil is far exceeding 300 to 400 F ?
That's basically what I was thinking. I can't see the water passages having anything to do with low oil pressure. Especially at start up... It should be up at 80-90+ lbs. There would be no heat in the engine to worry about..