Quoted from pdman:The real reason why the ball drops is that small ~ 1 1/2 space on the ramp behind the diverter arm collar and shaft that has no vertical metal piece there. It sure looks like one should be there.
I was having the same problem. My ramp welds had completely failed on the right side so I pulled out the assembly. There are indeed two vertical tabs missing from the ramp. I reckon they've broken off years ago cause I can see where the welds snapped. I found a pic online of the original assembly. Note mine has those tabs missing.
MY FAILED RAMP WALL