Scalextric cars with broken motor pinion gears

Classic Scalextric cars from 1970s and 1980s suffer from a problem whereby the little white plastic motor pinion gear on the motor shaft can crack over time.  The crack forms at the bottom of one of the gears and causes the pinion gear to lose grip on the motor shaft.  Also the gear which has the crack is now wider than it should be causing gear meshing problems.



So, how do you know if this has occurred?  In extreme cases the gear falls off the motor shaft giving the car no drive.  Less extreme is the gear loses all grip with the shaft but remains on the shaft, again there’ll be no drive.  In some cases the pinion gear grips the shaft a little which might be enough to turn the rear axle in low load conditions.

The first symptom is when the gear has split and still grips the shaft well.  In this case the symptom will be a regular clicking as the car is driven on the track.  If the car is used in this condition then the contrate gear on the axle will also be damaged.

The solution in every case is to fit a replacement motor pinion gear.

Another great insight from Scalextric Car Restorations