Drive Shaft Seal

I have a 95 hydrodyne, I know its not a Supra but still a great boat, anyways the driveshaft seal is dripping approx 1 drip per second, it is a white plastic nut and housing, it has a long cotter pin through both of them? I believe I just need to remove the nut and tighten it a little. Has anyone seen one like this?.

Thanks,

Fran

i know there are 2 different types of seals. this sounds right; all you should have to do is slightly tighten the nut. do you have any pics?

Correction, I meant to say remove the cotterpin and tighten the nut.