NFPA-20 does not allow this. It is a common mistake and is seldom caught by the local AHJ. It is common to find this configuration but it does'nt meet code.
End suction design has whats known as a overhung impeller with the bearing only on one side of the rotating element. As the load on this type of pump increases so does the deflection of the rotating element. They are primarly used where space is limited.
Split case pumps are better performing...
