Yamaha 25BMH 30HMH Factory Service Manual, Page 260Get this manual
CRANKSHAFT AND CYLINDER BODY
5Check: Crankshaft bearings Abnormal noisedamageroughness ReplaceCAUTION:
Do not use compressed air to spin the bearings dryThis causes damage to the bearing surfacesNOTE: Do not reuse the bearing, always replace it with new one