A valve cover assembly for a pump. In an embodiment, the valve cover assembly comprises a first cylindrical member having a central axis and a first throughbore. In addition, the valve cover assembly comprises a second cylindrical member coaxially disposed within the first throughbore and rotatable relative to the first cylindrical member about the central axis between a first position and a second position. In the first position, the second cylindrical member is axially translatable relative to the first cylindrical member. In the second position, the second cylindrical member is axially fixed relative to the first cylindrical member.