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Moth RCM just blown!

So I’ve fitted the new suppressor but sadly no difference. The disc motor will turn, but the vacuum motor will not.
I’ve spoken to Moth who say it must be a dead vacuum motor. Replacements are not cheap so I may just call it quits and find another RCM.
In saying that, it seems strange that the vacuum worked for a few minutes and then died quietly. No smell, no clicks or bangs etc. All wiring seems fine.
Any suggestions welcomed!!
 
You need to get a multi-meter and check some resistances.

I thought the most likely cause was that you disturbed or broke a wire in the connector block when you removed/replaced the suppressor. This might not be obvious if it's like mine with a 'choccy block' style arrangement. Add a bit of vibration when it was in use etc.

If you have a meter. then, taking the plug out of the wall, you should have an open circuit when nothing is on, switching on the vacuum should produce a reading of 9 Ohms. The turntable motor should produce 9kOhms, (it's a different type and much less powerful) If you go inside and find 9R on the vacuum motor wires then it's the switch. Vacuum open circuit then it's the motor.
 
Sorry for muscling in on your thread doctorf, but my issue seemed similar.
Looking at my suppression cap it was oozing some slime, so replacing the cap and the the RCM burst into life!
The vacuum motor was a little sparky to start with, but seemed to calm down after a couple of seconds.
I forgot how loud it is.
Thanks for your assistance everyone.
 
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You need to get a multi-meter and check some resistances.

I thought the most likely cause was that you disturbed or broke a wire in the connector block when you removed/replaced the suppressor. This might not be obvious if it's like mine with a 'choccy block' style arrangement. Add a bit of vibration when it was in use etc.

If you have a meter. then, taking the plug out of the wall, you should have an open circuit when nothing is on, switching on the vacuum should produce a reading of 9 Ohms. The turntable motor should produce 9kOhms, (it's a different type and much less powerful) If you go inside and find 9R on the vacuum motor wires then it's the switch. Vacuum open circuit then it's the motor.
I wish I had the skills!
 
Thanks.
I’ve got my multimeter out, but really haven’t a clue what I’m doing, so I’ll clean my few albums manually and return to the Moth when I’ve got the time and inclination.
a.p many thanks for your kind offer. I’m in Leeds, so not a million miles away. I’ll certainly message you if I’m coming down that way in the near future.
 
I'm sure someone on here can describe or point you to instructions for the multimeter procedure to measure the motor resistance. Even if the motor is the problem, for £78, surely it's worth fixing?
 
I'm sure someone on here can describe or point you to instructions for the multimeter procedure to measure the motor resistance. Even if the motor is the problem, for £78, surely it's worth fixing?
Thanks Stuart,
I will do a You Tube study of multimeter use and yes, I suspect £78 is well worth paying. In saying that, I have cleaned all my vinyl over the years so really now only do new albums when bought, so not many.
 
@Paul R do you have a wiring diag for this? Edit: a further thought, does the vac motor have a phase capacitor (I assume it does) so I wonder if that could have deteriorated esp as it is a much higher current motor. I recently changed the phase capacitors on some stuff at work that was 'reluctant' to start.
 
The wiring diagram is near the end of the assembly instructions for the kit version, this copy was linked up thread. https://svalander.se/local/site/files/tips_o_fakta/mothbyggorg1.pdf

The vacuum motor has only two wires, I assume it's an induction type. Mine measures 9 Ohms, and this can be tested without going inside the machine. Just switch the vacuum on with the machine unplugged and measure across live/neutral at the plug.

I think most likely is still that a wire has cracked at the terminal block, especially given its proximity to vibration and the effects of removing replacing the suppressor. Would be easy to check for me, or you, but quite hard to explain in detail. I'm sure doctorf can debug it.
 
Right, please bear with me.
I’ve removed the vacuum motor.
There are 4 black wires which attach to the motor as you look at it in the machine at 2, 4, 8 and 10 o’clock. If I touch 8 and 10 ‘o’clock together, there is an open circuit with 0 resistance. I cannot reproduce this in any other combinations.
Does this mean I need a new vacuum motor?
 
According to the wiring diag the vac motor has 2 black wires, the turntable has 4 wires: red, black and 2x white. Some detailed photos might help.
 
Not clear I'm afraid, but the motor is likely to have 4 terminals: 2 for the stator and 2 for the rotor. How many actual wires are there? There appears to be a single green or green/yellow and a single black wire at the top of your first image. Are these the two wires that were connected to terminals 2 and 4 of the terminal block?
 

I hope this makes it clearer.
On the left is the view from the top.
On the right from the bottom.
Thanks!
 
Sort of... what external wires connect the motor to the terminal block inside the machine as the instructions indicate that there should be 2 black wires? Have you disconnected the wires from the motor?
 
Sort of... what external wires connect the motor to the terminal block inside the machine as the instructions indicate that there should be 2 black wires? Have you disconnected the wires from the motor?
Yes, I removed them from 2 and 8 o’clock when I removed the motor.
 
Ah, so follow @Paul R instructions and use your DVM to measure between these two terminals which should be about 9 ohms. Set your DVM to the lowest range which is typically 200 ohm and you should read '9.0' or close by
 


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