Need to know how to line up the markings on the gears.

There's more than one model of cub.
Need to know which engine you have .
Cub has used about 5 or 6 different engines.

Model 2140, serial # 000254844 I got a new gear, but I need to know how to line it up onto the crankshaft.

The engine is Onan Elite. Four gears with markings on, and I need to know how to insert gear to the markings.