no flow at rear remote

i have a 5075m tractor, just got a split fire wood splitter today and tried to use it. all is hooked up right and works great but...only works when remote lever is pushef forward but stops flow to splitter when I push the remote lever all the way to lock it forward? I can tie the lever forward and it woks fine but why? it should work when locked forward?
this is the first time I have used the remotes on this tractor