Every Subaru is pretty much self bleeding, but you have to bleed as much as you can.
The overflow bottle isn\'t there to catch excess fluid in the cooling system, you should always have the overflow filled to the max line on the bottle (you\'re an idiot if it\'s empty). The way it works is when air is in the system it is relieved through the top hose in your expansion tank and towards the overflow bottle, this also creates a vaccum and fluid is then sucked from the overflow bottle back into the cooling system rather than air if it were empty.