Quoted from GSones:
After a bit of investigating, it appears that the flipper had too much up and down motion and was causing the plunger in the coil to bind a bit and the spring became over-stressed.
Shouldn't have mattered. If it broke on the end loop, these pictures will help you get going. You can get new springs if you don't have any as spares.
Here is a video using a flipper spacer gauge if you want to set how high or low the flipper bat rides. Not on a Houdini, but same principle :
If you don't have the official flipper spacer gauge, a business card works too, cut a notch in it.
LTG : )
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