The driveshaft is stainless steel and virtually indestructible. The crankshaft on the other hand is forged steel with the bearing areas case hardened. In order to keep the crankshaft splines from rusting they are lightly coated with grease and a neoprene "O" ring on groove in the spline is supposed to keep the grease in and the water out. In replacing the water pump you should always check to see the "O"ring has not been nicked by the edges of the spline and that there is a grease film on the splines. Be aware too much grease may cause a hydrostatic lock which makes it impossible to install the lower unit. In this case, the extra grease will have to be removed. Shortening the drive shaft in NOT an option . . . 😆
In other words the pinion gear, or the driveshaft and pinion gear may be missing . . . 🙁
