Great forum, enjoy all the knowledge. I have a 1982 630 with 958 hours on my machine. 30 hp Wisconsin air cooled engine. I have the original Ross drive motors and they are leaking into the chaincase. I want to replace the motors with the updated char-lynn motors. Can some people chime in who have done the job before? 1) Do i need to actually break the chain and install a master link or is it possible to walk the chain off and on? 2) How do the press on gears on the motor come off? Are they a bear? I have access to a shop press. For those of you who have done the job, how many hours did it actually take? Any tips and tricks would greatly be appreciated! Pictures etc.... I have searched the forum and can't find a specific thread on this job. I may have missed it but don't see one. Thank you very much for your time.