I recently got a L4150DT and it ran fine however , I drove it a 1/4 mile and hooked up to three point equipment and put the tractor in gear and it wouldn't move. Took home changed hydraulic filter and fluid , tractor did move and then quit again. The loader bucket will not go up and the three point is pretty much non existent . I took apart the return line in front of the seat and no fluid came out. Any help would be appreciated