Hammond M-100 (M-101) Run Motor Not Turning

[Composer]

My M-101 was working fine. I did not use it for a while and then switched it on. Amp hums softly, but no sound.

I opened the tone generation section. The start motor whirrs fine. When I then hold the 'Run' switch, the main tonewheel 'Run' motor jolts a turn for a couple of centimeters and then stops. A picture of the wheel that does not turn is attached. I can't see anything blocking the wheel. It turns OK if I turn it manually.

Please could someone advise as to what I should do to fix this?

[enor]

You say the start motor is "whirring" - but is it actually engaging, bringing the generator up to speed? Since you're saying the run switch makes the flywheel "jolt", it appears that it is not actually spinning by the time you hit "run"?

[muckelroy]

This is unrelated, but am I the only one who blinked twice at the 3-layer metal spindle on the flywheel? I have never seen 3 layers there, only 2.

You should be able to turn the generator shaft manually by hand, meaning the shaft to the right of the flywheel. If it's stiff at all, more oil.

Start motor has to engage the generator shaft. It might be spinning without engaging. Verify the bendix gear is moving to the left and engaging. In other words, the flywheel attached to the run motor has to spin when start is engaged.

[peterb_2795]

This is unrelated, but am I the only one who blinked twice at the 3-layer metal spindle on the flywheel? I have never seen 3 layers there, only 2.

Conversely, I have never seen one with two layers ... here are but two with three ... lol




I wonder if it is a side of pond thing because the OP was a 230V unit, and the two I have put photos up of are similarly 230VAC ?