Pioneer PL 55DX arm won't return to rest.

Just picked up a Pioneer PL-55DX with original box & assy. and fairly clean ,but has been setting up for a while. I de-oxed the pots & managed to zero in the speed. But the arm will not return to the test, makes to just outside the album /platter edge. SM only mentions to oil or replace the 1 & 2 plate. Is the no way top adjust the arm return? Tried to adjust the return speed spring. Now it slams the arm fast to the rest. I tried backing it off a little, then it would not make it to the rest. help.