When I run my Husky riding mower with hydrostatic drive it does not engage foward all the way. It will move and I can adjust speed with the lever but it is not fully engaged. When I take my heel of the left foot and pull the pedal toward me to the full off or released position it will then grab all the way and work fine.

Is this a belt adjustment or something else? If it is a belt adjustment what do I need to look for?