I have a 1982 Mercury 70hp 3cyl (SN#6164457)and I replaced the impeller a month ago and its already trashed. Every fin broke off at the base of the impeller. This was not installed backwards. The impeller was installed turning the drive shaft clockwise. But what I noticed was the impeller rubber was super stiff. Is this normal or was this possibly a new part that was sitting around too long? I also noticed that I can move the drive shaft up and down or in and out approx. 1/8". Should there be this much play in the drive shaft? I would like to put a new water pump rebuild kit in but I dont want the same thing to happen again. Any advise?