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Author Topic: DC15 Brushroll Motor Voltage?  (Read 267 times)

Offline macman

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DC15 Brushroll Motor Voltage?
« on: May 13, 2024, 05:38:22 pm »
Only the second DC15 I've ever seen, and what a complex beast it is!
This one has has an intermittent brushroll fault: it starts up, but then stops as soon as the machine is pushed forwards.
 Could be a faulty PCB, a break in the yoke loom, or (I hope not) a failing brushroll motor.
What voltage should I be getting off the PCB motor terminals with the machine reclined please (I'm assuming it's a DC motor)?

Offline Dysonboy

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Re: DC15 Brushroll Motor Voltage?
« Reply #1 on: May 15, 2024, 12:15:17 am »
Only the second DC15 I've ever seen, and what a complex beast it is!
This one has has an intermittent brushroll fault: it starts up, but then stops as soon as the machine is pushed forwards.
 Could be a faulty PCB, a break in the yoke loom, or (I hope not) a failing brushroll motor.
What voltage should I be getting off the PCB motor terminals with the machine reclined please (I'm assuming it's a DC motor)?

if it’s stopping with movement it will be the wiring loom damaged creating loss of connection at certain point. If it were the PCB it would work point blank, or would struggle with load, not movement.
Collector and restorer of most vacuum cleaners including vintage, older style models and newer models. Seller of refurbished vacuums and vacuum parts Livin' every day, as if it were the last!

Offline macman

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Re: DC15 Brushroll Motor Voltage?
« Reply #2 on: May 15, 2024, 07:34:25 am »
It's not the yoke loom, I have tested the continuity. It's not movement as such that stops it (i.e. waggling the handle), but pressure on the brushroll when placed on a carpet and pushed. On a hard floor it spins freely. So I suspect the motor is failing under load.
After stripping the head, I found that the motor is the same as that in the DC25 (Johnson DC771(2). Assuming the gearbox can be swapped over directly, I'm going to rebuild it with a used DC25 motor to see if that solves it.
Will also check the PCB output, which should be around 320V DC, same as the DC25?
If a motor swap doesn't fix it, then it can only be the PCB failing under load, as you suggest.

Offline macman

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Re: DC15 Brushroll Motor Failing?
« Reply #3 on: May 17, 2024, 01:11:14 pm »
I now think that the issue with this machine may be the recline microswitch, not the brushroll motor.
I have tested the continuity on the microswitch loop, and, weirdly, it seems to be the wrong way around! With the wheels up, there is no continuity. With the wheels down, there is continuity. Surely this should be the other way around?
I'm also unclear about which other components need to be removed to access the microswitch: does the whole yoke have to come off first? I have studied Beko's stripdown guide, but not quite clear which sequence to follow.
Can anyone help please? This one is really baffling me.


Online MVacs

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Re: DC15 Brushroll Motor Voltage?
« Reply #4 on: May 18, 2024, 08:55:02 pm »
I found that the motor is the same as that in the DC25 (Johnson DC771(2). Assuming the gearbox can be swapped over directly, I'm going to rebuild it with a used DC25 motor to see if that solves it.

I seem to recall the cog differs. IIRC the DC25 motor won't run a DC15.

What you describe does sound like a duff motor. But that loom is notorious too.

Although, we had one this week where the motor was playing up and the gearbox was clogged up with crap. A strip down and clean solved it.

Offline macman

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Re: DC15 Brushroll Motor Voltage?
« Reply #5 on: May 18, 2024, 10:06:10 pm »
You are quite correct: I was wrong about the motor. When I stripped the gearbox, I realised that the drive shaft metal cog is bevelled: the DC25 is straight. The actual motor itself is the same model number, which is why I thought they could be swapped.
I have continuity tested the yoke loom and that is OK. Next job is to swap the motor you just sent me and see if that cures it.
If not, it must be the PCB or microswitch: the former has no signs of damage though.
But I still do not understand how the continuity can be reversed on the microswitch loop, this makes no sense.
And I can't see how to access the microswitch housing: does the yoke have to come off first?

Online MVacs

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Re: DC15 Brushroll Motor Voltage?
« Reply #6 on: May 20, 2024, 12:47:15 pm »
Beko did a strip down on one of those >here<.

I'd expect to see damage on the PCB if that is duff. The motor seems most likely from your OP.

Offline macman

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Re: DC15 Brushroll Motor Voltage?
« Reply #7 on: May 27, 2024, 04:48:21 pm »
Conclusion: I have to eat my words, as it turned out to be just the yoke loom, after all that.  I had already tested it for continuity on the machine, and it was OK. But, when I removed it and retested it, it failed on one side when stretched out in a straight line. They break internally at the point where they pass through the little rubber grommet, which is obviously the the weak spot.
Lesson learnt: to always test components on and off the machine. Why it seemed to run OK on hard floors but not on a pile carpet, I'm not quite sure. But the motor seems to be in good condition, it just needed a good cleaning.
Anyone want to purchase a now surplus-to-requirements DC15 brushroll motor and PCB?


 

 

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