Abstract: The valve assembly tools include a longitudinally expandable member insertable between the seats in a ball valve to forcefully displace the seats into a retracted position in the seat pockets. Seat securing devices are temporarily mounted in the valve body through seat lubrication apertures so they can temporarily engage each of the seat assemblies to secure them in the retracted position. When assembling a valve the seats are displaced to the retracted position by using the longitudinally expandable member and they are temporarily retained in this position by the seat securing devices so the expandable member can be removed. Next the ball valve member is positioned between the seats and then the seat securing devices are released to allow the seats to move into contact with the ball valve member. The seat securing devices are then removed from the valve body and assembly of the valve is continued.