On the rear left side of my engine block, 3 or 4 inches above the oil pan seam, there is a tapped hole, apparently for coolant drain from the block. Last winter (I know - for some it still is winter) I drained the block and radiator, just for good measure. So now, I am re-filling the coolant (anti-freeze this time for permanent solution), adding it through the thermostat port. I notice that no fluid is flowing out the block drain port (it did when I prepped for winter). However, if I blow air back into the drain port, it bubbles right back out the thermostat port. Am I just not getting the coolant past the water pump?
