A few years ago my boat had a similar issue...The rack had move away from the pinion and damaged the rack....Replaced the cable which took using a cherry picker to remove the 150 VMAX from the transom as the cable could not bend sharp enough install it...Anyway I would suspect you need a new cable with the rack being part of it...Research boating/marine supply houses....They will require you to measure the cable length....Hopefully you will not have to remove the outboard to install it as I did..Good luck...My cable was a Teleflex and cost a bit over $200 ...You should see a brand name stamped onto the cable.....Another alternative is to change to a hydraulic steering system....Under normal conditions your pinion will be centered in the distance of the rack to enable you to turn both directions equally....If not centered you may be able to turn only one direction as you described...