Automower 420, 430X, 440, 450X, 520, 550, 550 EPOS front wheels repair and modification

This tutorial applies also to Automower 310, 315, 315X, but since spindle shaft’s diameter is smaller (6 mm), ball bearings, shield kit and shaft lock collar are different. Automower 105, 305, 405X, 415X, 310 mark II, 315 mark II, 435X and 535X use different type front wheels. Tools used: T20 Torx screwdriver Angle grinder Rasper / file Milling cutter 16 mm Allen / Hex key Torque screwdriver (accuracy at least one decimal place) Parts used: Ball bearing 688 (8 (ID) x 16 (OD) x 5 (Width) mm) with contact rubber seals (types: 688RS, 6882RS, 688RZ) Slicone grease or grease, which is safe for plastics and rubber Oil seal 12x18x3 mm Stainless steel lock collar T8 (8 (ID) x 14 (OD) x 7 (Width) mm) O-ring 80x5x90 mm O-ring 2.5x1x4.5 mm