In this video series, I am working on a client’s “Dr. Who” pinball machine that wouldn’t boot up. It was just dead. None of the diagnostic LED blinks would blink on the WPC-89 MPU board, so I go over the process of how to identify and isolate the problem, then I upgrade the board with NVRAM (non-volatile memory) so that it will never need batteries again.
As I continue working on another new machine, Bally’s “Black Rose”, the first order of business is to go over the flippers and other areas where parts are not working. This series focuses on basic problems that occur with pinball flippers and also addresses an issue involving a broken ball kicker (the same assembly that is used on slingshots). Here I address everything from replacing a coil, coil stop, coil sleeve, to determining which parts to replace and which ones to save, as well as wiring problems, end-of-stroke switch problems, flipper bushings and more.
When I first got this game the system diagostics reported an unusual error: “Upper flipper EOS switch stuck closed.” That was a sign that someone had monkey’d with the machine and not done things right. As you will see in the videos, there ended up being a plethora of problems with the flippers in this game, each representing some of the most common problems with modern pinball machines. I go over how to fix them.
In a nutshell, the following issues were found and corrected:
- flippers needed cleaning and coil sleeves replaced
- bad wiring job on one flipper
- broken/improperly-installed EOS (end-of-stroke) switch
- bad coil stops that needed replacing
- fixing and re-shaping coil pistons
- replacing a damaged/melted coil and sleeve
- fixing a broken armature on a ball kicker (same assembly for slingshots)
- replacing a broken flipper bushing
- replacing a flipper return spring that was the wrong type
You may be wondering, why was the machine reporting only one thing wrong when there were so many other issues? Not everything that is wrong with a pinball machine can be diagnosed by the software. Obviously things like sticky flippers or dirty coil sleeves can impact performance but still make the game think everything is working. The same thing goes for the kick-out coil. The game wasn’t quite smart enough to know it wasn’t working. One way the game determines if certain features are working is to keep track of how often they are triggered and if a certain number of games is played, without a certain feature activating, the game can sometimes report things broken. Other times, things may be broken but they are still being triggered (like the kick-out solenoid). So it’s always best to go over everything carefully to make sure there are not more problems than what is indicated.