Graeme expressed precisely :
Harry, the problem is that these devices have rarely if ever worked properly
since new. There just isn't enough heat to turn the beacon. It is sometimes
possible to get the beacon moving for a while with a quick nudge, but it
rarely spins for long. Another manufacturer (Lionel) had a similar product
which they withdrew and replaced with a motor powered beacon because the heat
version was unreliable.

Assuming the 'heat version' relied upon waste heat from the lamp, a
resistor could provide much more heat than a bulb.