This service manual should be of some help. Follow berts and mackies instructions and you should be able to solve your problem.
http://www.mymowerparts.com/pdf/Kaw...FD791D-DFI-KAWASAKI-SERVICE-REPAIR-MANUAL.pdf
http://www.mymowerparts.com/pdf/Kaw...FD791D-DFI-KAWASAKI-SERVICE-REPAIR-MANUAL.pdf