There is a course adjustment via a quadrant on the main pulley. Can't send more detail but Dillen will know what I mean and be able to send instructions.Check that the carriage wire has been fitted correctly;
It has a small knot from factory, that needs to sit in a small cutout along the ridge across the cam wheel it has been fitted around.Martin
Adjust the 17cm set down first with the excentric then fine tune the 30cm set down with the quadrant on the pulley'
I no longer have access to the service manuals to enable me to be more specific!