Speaking of the male tips, a neighbor was mentioning he was having grief with brands other then the genuine Pioneer, in fact he had one spit its guts out and luckily it jammed into an elbow fitting or some place where he found it. Unfortunately some of this cheap or not so cheap to buy, but a cheap brand, it can bite a guy in the butt.
I don't know if that's true but I was told the poppet style male end may have a bit more flow over the ball style. About all you can do is replace one and try .. keep repeating until you've replaced all the male couplers, or upsize them if possible.
What speed can you get out of your fan, mind you it would depend where the air baffle flaps are set for air flow but just to get an idea of your fan speed might indicate how well the oil is flowing.