Older Rainsoft Sync Problem

the two disks are keyed to the hex staft. once it's all together,keep it on bypass, plug it in and let it run. if it's a manual timer, it will reset itself back in the ser position, this could take a couple of hours. After the switch levers are in the ser position you can take it off of bypass. I would put a cup of chlorine bleach in the brine tank with a couple of gallons of water and run it throung a cycle to sanatize the unit. did you replace the orings on the piston? this is probably what caused the shear pin to break. also do not use any petroleum based lube on the orings. use dow111 or equal