The saga of the knocker - part 1

One of the interesting pieces of a pinball game is the "knocker." This is the device that makes a loud distinctive sound when you match and get a free game.

On the Star Trip, the knocker solenoid was fried. I found this some time back and had disconnected it (removed the wire) - now it was time to try and fix it.

Step 1 - removal

I pulled it out of the cabinet. It is strange looking compared to the other solenoids:

The dark band around the solenoid shows it is burned. I took everything apart. it has some unique features. There is a long plunger with a copper end on it and the plastic tube sticks out much further than any other ones I have seen.

Checking inside the tube, it looks like there is a wad of gum in there!

After checking with the experts, I found out that:

1) the "knock" sound is the plunger striking the bare side of the metal assembly
2) the "gum" is actually a severely melted plastic tube
3) I will need to replace everything but the metal

Off to order more parts!