Hello..I am new to hydraulics and tractors. I have a Kubota BX24, and i was using the backhoe yesterday, and all of a sudden I lost most control of my Left Boom swing. When I go right it goes nice and fast, and all other controls and FEL work fine. It goes left, but real slow and you can hear the hydraulic pump working like it is bogged down when I move the control. I checked the fluid level and everything seems full and normal. I let it sit overnight and same thing today. Any ideas? Could it be air?