Your right, there should be no leakage out of the weep hole. Of course if the shaft was scored or had a seal groove, etc and they didn't change that as part of the rebuild then your lucky that a drop is all your getting. Nowdays your usually better off to go the aftermarket route and just get a new pump rather than having an old one rebuilt. One note on the aftermarket pumps. Unless the "CAT classic" pumps have changed significantly in the past few years stay away from them. The first, and only one of them I bought for a customer had to be swapped out three times and every one of them leaked worse than the origional pump. Wound up taking the third pump and buying a rebuild kit for it to get bearings tight enough to keep the shaft centered enough for the seals to work.