2004-2005 660 Yamaha Rhino Factory Service Manual, Page 311Get this manual
FRONT AND REAR BRAKES
CHECKING THE MASTER CYLINDER 1Check: brake master cylinder Wearscratches Replace the brake master cylinder assembly brake master cylinder body Cracksdamage Replace brake fluid delivery passage (brake master cylinder body) Blockage Blow out with compressed air2Check: brake master cylinder kit Scratchesweardamage Replace as set Primary brake master cylinder kit Secondary brake master cylinder kit