2003 Polaris Deep Snow Snowmobiles Service Manual, Page 302Get this manual
BRAKESFINAL DRIVE Hydraulic Brake Cleaning and Inspection
Check all parts for wear or damage and replace as requiredAlways replace caliper piston seal and dust seal (where applicable)1Clean all parts with denatured alcohol and wipe dry with clean, lint free cloth2Using compressed air, blow out the drilled passages and piston boreBe sure piston seal groove is thoroughly clean and free from corrosion or brake fluid build up3Inspect piston bore for scoring, pitting or corrosionA corroded or deeply scored casting should be replacedLight scores and stains may be removed by polishing with crocus cloth onlyUse finger pressure and rotate the crocus cloth in the cylinder boreDo not slide the cloth in and out of the bore under pressureDo not use any other kind of abrasive cloth4Check piston to see if it is pitted, scored or wornIf so, discard and replace the pistonCAUTION: Do not attempt to polish or sand piston5Clean piston with denatured alcohol and wipe dry with clean, lint free clothUsing compressed air, blow dry6Check inlet and bleeder hole threads for damageBe sure bleeder screw is clear7Inspect brake line seat for damage and replace caliper if necessary