Home › Forum › Ask A Member › 40/48/50 gearcase driveshaft removal › Re: 40/48/50 gearcase driveshaft removal
1995 was the first year OMC made a 3 cylinder 50hp motor. Of course it had the 3 cylinder gearcase. It is important that you learn family’s of engines in a product line. Even if it is Mercury or Yamaha. There were some strange combinations of driveshaft for the top splines in order for them to fit various 2 cylinder & 3 cylinder motors, but generally the small tube gearcase fit the 2 cylinder motors and the large tube fit the 3 cylinders & above. The exception to the rule was commercial engines. If you look at the pinion nut you can tell which driveshaft you are dealing with. #313339 (5/8" wrench) is small driveshaft, #314730 (7/8"wrench) is large driveshaft.
Dan in TN