I just added a flipper rebuild in my 1980 Blackout. When I played it, the flippers seemed weak with not much power and jittering. I adjusted the EOS switch a few times with no improvement. I then reflowed solder to all the coil and flipper connection and still no help.
The flippers feel fine until they transfer to low power when hitting the EOS switch. My best guess is that the new coil springs are to tight and pushing the plunger back into the EOS switch, which is making the flippers jitter and weak. I'm thinking of cutting and shortening the coil return springs to lessen the spring power. Additionally, the plungers are moving smoothly into the coils and the flippers are not to tight against the play field.
Anybody have this happen to them? My next step is to cut down the coil springs or put the old ones back on.