[ajmac]

Having cleaned up the ones that I have I can get the ball to move against the spring but it doesn't seem to seat properly at all as you can blow and suck from the threaded end. I would presume that it should only let air pass out or at least have some sort of bias or it might as well just be an orafice! As I cant believe that it gets too hot I am inclined to just fit two grease nipples. What is peoples experience?