I am having a problem with the tranny on my 4514. If I'm on a flat area the thing does really well, but it will not pull a hill, even a small one. I've been told that I should check the fluid and bleed out the air. The fluid looks fine and is the right level, but I can't see any way to bleed the air. Can anyone walk me through it? I don't have a service manual for it because I bought it used. I've also been told that there really isn't anything in the tranny that should go bad. Any ideas would be appreciated.