texascowboy9168

I have recently replaced the ps pump because the pulley was literally sliding itself off when the belt was connected, so i thought the shaft the pulley sits on could be stripped, was running good for about a month with new pump until this afternoon same problem, except now with the pump installed, i can not fully press on the ps pulley so again it keeps sliding off... any suggestions on A. Why the pulley slid off when it was fully pressed on, and B why i cant fully press on the pulley now and why its still sliding off.