I just replaced a couple of things and had to drain the radiator. Need to get the truck back on the road but will have to drain it again soon for some other work. Any issues running straight water now that it's warm out? Does it have to be distilled? I grew up in the third world and we always used water but I've heard it's bad for the pump.
The anti-freeze does lubricate the bearings in the pump. A few weeks, not big deal. In any event, antifreeze is cheap and if you have to drain it, you can always catch it and put the old new stuff back in.