5- 10 if they go easy. I go depending how long ago it was serviced.

The nature of the beast is that you should pump grease in until you see just a bit of grease emerge from one end of the spindle. Hopefully it comes out the blade end (it usually does). Pumping too much grease might result in it coming out on the pulley end and you don't want that because you could foul a belt.
And you should also be very careful about pumping the grease in too rapidly. I suggest using only a hand operated grease gun to pump the grease because the bearings actually do have a seal in place on them. They are still able to take grease because that seal is attached only to the OUTER bearing race (the part that fits to the spindle housing) and it is only a lip type attachment at that. The seal is not attached at all to the inner race (part that fits to the spindle shaft).
Greasing these spindles should be done using slowly administered strokes of the grease gun so the grease can enter....and exit past the inner race without blowing the seal out of the bearing.
Probably some naysayers on this but that's OK.

Thanks, it's been about 35 hours since the last service (that's about what I average per season). I was curious as to how grease made it to the top bearing without it being filled. Did not want to over do things.
Thanks again.

That's the thing. Generally lower spindle bearings will fail well ahead of the upper. It almost seems the taller the tower though, the longer the uppers will last. When you put on new spindles that are empty and need lube, they spec 10-15 pumps on several I've seen. I don't disagree with using more grease, but unless you pretty much pack it- I'm guessing the grease is spun away from the top bearing. I'm personally more diligent in greasing spindles w/ Timkin bearings though. Mownie won't let me work on his stuff anymore since I started using a power grease gun.:) Love the thing.

Well tom, you can use it on everything except my spindles.
:^)

I had a grease cap blow off a trailer one time because someone over filled the hub with grease. One trip, a little hotter and it was gone.
Thanks again.... One of the few places on the net to get help like this.

"Filled" the spindles with grease yesterday afternoon. Went slow, on two spindles, grease oozed out the bottom of the spindle. On one it started out the top. When I saw this, I "vented" the zerk by pressing in the ball with a screw driver. Some grease vented out of the zerk, but not much. I was really surprised at how much grease this took. Man what a difference sharp blades make cutting grass. I would have posted some photos of the yard, but it was geting dark when I finished.

From this point on, you will probably only have to add 2 to 4 pumps when you grease the spindles.
It is possible that the spindle where the grease wanted to emerge from the pulley end has accumulated an "extra seal" of wound up grass or string ahead of the actual bearing seal on the blade end of spindle.
I would not bother to check for that as it is unlikely to cause a problem.
Having some grass wound around in that place is pretty normal anyhow. Just about every spindle I ever took apart had some wound up grass and sometimes a piece of string between the deflector cup washer and the bearing.