If this is a belt drivin transmission and the belt was replaced with a normal oval setup up it may be the reverse of the direction it needs to be turned. Try creating a figure eight with the belt make the direction change.I hope this helps.
Try the O rings around the shaft of the pump that the drain hose is connected to. These rings are made of rubber and when rubber gets dry it shrinks or loses some of its shape and creating a leak. I hope this helps
