12. CRANKCASE/CRANKSHAFT ATV 50 SERVICE INFORMATION GENERAL INSTRUCTIONS · This section covers crankcase separation to service the crankshaft. · The following parts must be removed before separating the crankcase. Engine ( Section 6) Driven pulley ( Section 9) Carburetor ( Section 5) A.C. generator ( Section 8) Oil pump ( Section 4) Cylinder head/cylinder ( Section 7) Reed valve ( Section 5) · When the left crankcase must be replaced, remove the following part in addition to the above. Final reduction removal · Special tools must be used for crankshaft and crankcase assembly. When separating the crankcase, the bearing will remain in the crankcase and it should be removed. When, assembling, drive a new bearing into the crankcase and install a new oil seal. SPECIFICATIONS mm (in) Item Standard Service Limit Connecting rod big end side clearance 0.6 (0.024) Connecting rod big end radial clearance 0.04 (0.0016) Crankshaft runout A/B 0.15 (0.006)/0.1 (0.004) SPECIAL TOOLS Crankcase puller A120E00026 Universal bearing puller A120E00030 Crankcase assembly tool (left crankcase) A120E00024 Crankcase assembly tool (right crankcase) A120E00016 Oil seal & bearing driver A120E00014 TROUBLESHOOTING Abnormal engine noise · Excessive crank journal bearing play · Excessive crankpin bearing play · Excessive transmission bearing play 12-2