About 3 months ago I decided to start up the old Hammond organ. I haven't played it for decades. My dad used to play every now and then. Mostly when I was at work (thank goodness - he used to look at music but play by ear!) It produces it's notes with a tonewheel generator which consists of 74 small wheels with varying number of notches on them. They're all driven by a central shaft about 80 cm long and are spaced on either side of the main drive shaft. The number of notches on a particular wheel determines the tone produced as the notches spin past a magnetic pick up coil. The generator has 
to be oiled regularly and it hadn't been oiled regularly since I don't know when. It started with some terrible screeching sounds. I switched it off immediately and went onto the net to learn more about the Hammond tonewheel generator and where I could buy more oil, as it had to be genuine Hammond oil or untold damage could be done to the generator so the forum messages said. I had some good quality clock oil so I poured some of that into the filler holes and left it for a month.
to be oiled regularly and it hadn't been oiled regularly since I don't know when. It started with some terrible screeching sounds. I switched it off immediately and went onto the net to learn more about the Hammond tonewheel generator and where I could buy more oil, as it had to be genuine Hammond oil or untold damage could be done to the generator so the forum messages said. I had some good quality clock oil so I poured some of that into the filler holes and left it for a month.
I stared it up again a month later and it sounded much better. I noticed a "C" note was dead, so I decided it was time to open it up and investigate. Everything was covered with years and years 
of dust, cobwebs and some empty cockroach egg shells. So I pushed the organ into better light in the kitchen and proceeded to pull it apart and clean and vaccuum all the dust etc out. I replaced a flaking chipboard shelf, chips were falling into the tone generator and I didn't think that was good. I fixed two supports for the generator to stand on while I cleaned that up, removing oil-laden dust from the transformers and capacitors. I managed to find an almost complete service manual on the internet with the hope of tracing the 
missing C note. I joined the Hammond Zone forum and found others had similar problems with missing or dead tones. The usual suggestion was to check the soldered connections where the wires go from the generator to the keyboards, and at the capacitors and resistors on the transformers. I checked all the wires but found none broken or disconnected. I managed to locate the broken tonewheel from a chart on the net. I connected it's pickup coil wire to another connector and found it was definately dead. I then connected another tonewheel I knew was playing to the same middle C on the manuals, and it played. So the problem was somewhere in the pickup coil inside the works and from what I'd read on the forums fiddling with the tonewheels was definately not recommended as it was a "very precice piece of mechanical engineering and special jigs were needed to assemble it". I needed to get that magnet out and check the coil!
of dust, cobwebs and some empty cockroach egg shells. So I pushed the organ into better light in the kitchen and proceeded to pull it apart and clean and vaccuum all the dust etc out. I replaced a flaking chipboard shelf, chips were falling into the tone generator and I didn't think that was good. I fixed two supports for the generator to stand on while I cleaned that up, removing oil-laden dust from the transformers and capacitors. I managed to find an almost complete service manual on the internet with the hope of tracing the 
missing C note. I joined the Hammond Zone forum and found others had similar problems with missing or dead tones. The usual suggestion was to check the soldered connections where the wires go from the generator to the keyboards, and at the capacitors and resistors on the transformers. I checked all the wires but found none broken or disconnected. I managed to locate the broken tonewheel from a chart on the net. I connected it's pickup coil wire to another connector and found it was definately dead. I then connected another tonewheel I knew was playing to the same middle C on the manuals, and it played. So the problem was somewhere in the pickup coil inside the works and from what I'd read on the forums fiddling with the tonewheels was definately not recommended as it was a "very precice piece of mechanical engineering and special jigs were needed to assemble it". I needed to get that magnet out and check the coil!
In the mean time the motor capacitor almost burnt out. It got extremely hot while the organ was running while I was testing and tripped the house circuit breaker. I have not managed to find an exact replacement but someone from work gave me a capacitor he had which is doing the job for now.Today I decided it was now or never and I started opening up the metal frame of the generator to remove the magnetic pick up coil. It
was quite a mission but with a bit of "gentle persuasion" I managed to get it out. I inspected it with a magnifying glass and found one end of the hair-width wire on the coil had broken where it was soldered to the terminal. I unwound some wire and soldered it back and put the pickup back in the generator. Fortunately the offending pickup was right on the end so it was not necessary to open the whole generator up, and I didn't need to use the special jigs to get it back together! either!! Just lucky I suppose.When I'd reconnected the wires, I switched on and gingerly played the "C" note.
IT WORKED!!!!
PS. I've ordered some Hammond oil from someone in Canada as there is none available in South Africa although someone I know who has worked on the organ in the past said good sewing machine oil is ok, but I don't want to take any chances.
PPS. This organ is now for sale. Any takers?
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