D311 (D2-5U) water pump question

Hello everyone,

in in the course of replacing my weeping original leather front main seal, I decided to freshen up the water pump with new grease seals, bearings, water seal, gaskets, etc. I have it fully assembled and mounted (minus the radiator and belt) and am curious as to a proper torque or tension for the outer nut which holds the fan blade on. It seems that too much and there is a substantial amount of drag, where as just a bit past touching seems to feel perfect, in terms of rotational drag. Bearings and all seals are factory caterpillar parts and lubricated where needed.

Any insight is much appreciated!

Thanks Much,
Breadler