The Tonewheel Generator

The sound on these older Hammond organs is created by a series of mechanical revolving tonewheels and magnetic pickups. This complex mechanism requires oil, as the label here shows.

Unfortunately, this particular organ hasn't seen any oil for years. Possibly decades. The whole thing is noisy when running and the high B tonewheel is not working properly. There is sound, but it is not even close to being correct.

Here the cover has been removed. This end has the main synchronous motor and the vibrato scanner.

The red objects on the top of the generator assembly are capacitors. Generally the red ones are more desirable than the alternative brown/yellow paper and wax ones. The older paper types dry out and the values can change dramatically, seriously affecting the sound.

Some people suggest replacing all the capacitors regardless of age or type, but this is not as simple as just buying new ones and soldering them in. Even small variations in the values will cause significant changes to the sound.

This is the other end of the generator, where the starting motor is located. The main motor does not start on it's own, and must be spun up to speed before power is applied.

This organ has a useless modification fitted. Someone has added a metal rod with a wooden block on the end. Presumably this was used to move the starting motor gear into position.

This is completely pointless. The starting motor includes a spring gear for this purpose. This evidently became sticky at some point, so adding some oil there woudl have solved the problem. Instead, someone went to the significant bother of adding this dubious modification.