This post explains why the games goes into ball search when two balls are locked in the portal lock. (Basically the rightmost finger is too low as shown below so the ball rests past switch 47 and “lost”.)
Others may have posted similar photos. Here is what I found with my subway. I have reported this same information to Pablo at Stern Support.
I believe the solution would be a spacer strategically placed that would stop the bottom bar from moving from center and allowing the finger to slide between the bar and the body of the mech. I am just trying to figure out the best way to do it. But would prefer a real solution that can be shared from Stern. What if the white plastic rod that attaches to the coil plunger was extended another inch towards the Ant VUK? This may give the rightmost finger the stability it is lacking that would stop it from moving back towards the white plastic bar and allowing the finger to fall between the metal bar and the front of the mech.
I took the subway mech out and I see the issue. There is too much slack of space on the right most finger and the finger falls below the metal that it is supposed to be resting on.
I lifted it back up and it works nicely for a few times and then gets wedged in between the front of the mechanism and the metal bar that the finger should be resting on.
The first photo shows the rightmost finger all the way down. As shown in the next photo, you can see the reason, the finger gets wedged in between the front outside and the bar.
The second photo shows that there is too much space between the front of the mechanism and the bar that the finger is supposed to rest on. So the finger actually goes below the bar and is wedged between the front of the mech and the bar. You can see the semi circle of the finger in the hole below the yellow/orange/green wires.
The third photo shows I can lift up the finger so it is in a good position. But after a few manual pulls of the coil, the finger will get lodged between the front mechanism body and the bar that it should be resting on top of and look like photo 1.
In the fourth photo, you can see how much excess room there is between the mechanism and the bar where the finger gets lodged in the right most hole. If you look at the middle hole, there is much less clearance for the finger to get lodged.
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