Nice explaination Owen. Tell me what is the purpose of the plastic coil sleeve and its importance. I always hear you should put a new sleeve when rebuilding flippers for example. I know it a cheap thing but whay is it important to do so. What tell tale signs indicate a woen sleeve, week flipper, fuses blowing??

Coil sleeves act as a "buffer" between the coil and the moving plunger. The wear that the plunger causes over time is on the coil sleeve, not the coil itself. A coil sleeve is a consumable item - like a rubber. Over time, the wear from the friction causes the plunger to become "Sloppy". Ops used to spray lubricant on the exposed plunger and then this would prevent the friction, and therefore the "sloppiness'.. Over time, the lubricant attracts dirt from inside the machine, which becomes a sticky deposit, which then causes the "sloppiness", until the plunger eventually seizes inside the coil sleeve.

Even after YEARS of the plunger not moving, you can simply clean the plunger with alcohol or nifti, and replace the coil sleeve, and the plunger is happy again !

It is a cheap way of having your machine running as best it can.. Every 10 years, just replace all your coil sleeves..