Could be wrong here because I am trying to visualize what could be going on and could be picturing it incorrectly, but it sounds to me like maybe you have a mis-matched set of pulleys.
Assuming this is a non AC, power steering setup, you should have a two groove pulley on the crank, with the inner groove slightly smaller than the outer (if my memory is correct). On the water pump, you should have a single groove pulley that lineup with the inner groove on the crank. The alternator should have a single groove as well, although I have seen a double groove alternator pulley line up fine before. The alternator and water pump both run off the same belt, and should line up with the inner groove on the crank pulley. The power steering pump runs off the outer groove on the crank pulley and doesn't run anything but the PS pump.
Again, just trying to see it in my head, but it kind of sounds like you are trying to run the PS pump off the inner groove of the crank pulley, or you have a 3 groove crank pulley which is for an AC setup and probably won't work at all.
Just as a reference, pretty sure the AC setup ran the PS pump and water pump on the same belt, while the AC compressor and alternator where on a pair of belts. That setup uses a shorter water pump pulley and neither the water pump pulley nor crank pulley will work without the AC compressor.
Maybe that helps? Just an idea.
