as i have seen, usually in ic engines, the oil is forced into the journal bearings and then it travels along passages in the shaft to connecting rod bearings. but how, does it enter the passages in main bearings with so much centrifugal force. if i understand correctly, the cetrifugal force is the reason it is emitted at other bearings. also, does the lubricant function as coolant? or do we use lube+coolant?