Not trying to re-invent the wheel here . . . just don't enjoy taking a bath in axle grease and not knowing if I have air cavities inside the hub . . . anyway my hubs came factory plain so I added Zerk fittings and a bleeder hole so I can monitor the condition of the grease.
I found that if I install the hub on the axle backwards and without the seal installed, I can power lube one bearing at a time and don't have to worry about bellowing the seal. Then I removed the hub, "press" the seal in, to keep from dislodging the grease, then power lubed the outside bearing. With the hub off, while reversing position, I can see there are no "voids" inside the hub.
Just sayin' . . .
I found that if I install the hub on the axle backwards and without the seal installed, I can power lube one bearing at a time and don't have to worry about bellowing the seal. Then I removed the hub, "press" the seal in, to keep from dislodging the grease, then power lubed the outside bearing. With the hub off, while reversing position, I can see there are no "voids" inside the hub.
Just sayin' . . .