Tohatsu 4 Stroke MFS 2/2.5/3.5A Outboards Service Manual, Page 44Get this manual
2 Remove lower unit installation bolts and nut 4, and pull lower unit ass'y downward to removeCheck drive shaft spline for adhesion of oil, rust and wearRemove bolt, and then, pump case (upper) while pushing drive shaft downward When removing or attaching water pump and pump case (lower), be careful that the drive shaft is not pushed up Pushing up the drive shaft causes pinion (B) gear to drop into the gear case
Remove impeller 2Check pump case (upper) for deformationReplace if necessaryCheck impeller 2, pump case liner and guide plate for cracks and wearReplace if necessarya Projecton c