Author Topic: Electric motor repairable?  (Read 2534 times)

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Offline jonda500

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Re: Electric motor repairable?
« Reply #25 on: June 05, 2017, 09:03:03 PM »
The only thing that I could see amiss under the little cover was the reverse instruction sticker had come unstuck from the underside of the cover and was resting on the contacts. A PO has obviously soldered in a replacement power cord at some stage...
I'll post anything else I can find out when I get it all apart.
Remember that an ignoramus is only someone who doesn't know something you just learned yesterday!

A starter clutch thread:
http://forums.sohc4.net/index.php/topic,122084.0.html
1972 CB500K1 original 4 owner bike
1972 CB500K1 returned to complete/original condition
1975 CB550F built from parts - project thread:
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197? CB500/550 constructing from left over parts
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Offline TwoTired

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Re: Electric motor repairable?
« Reply #26 on: June 05, 2017, 09:05:49 PM »
Pretty much anything can be fixed, given enough time money and effort.  Have you attacked it with a multimeter yet?  Checked for continuity?

In the early sixties, I rewound my neighbors washing machine motor as a high school shop project.  The starting winding was fried since it didn't cut off when the armature attained speed.  Tedious work done in a series of classroom work periods, removing the burnt windings, and laying in new copper windings.  Neighbors were elated to have their washing machine working again.  And I got a good grade.

Btw, know that 1hp is 750 watts.  Your 888 is likely the start up consumption, not continuous duty, which is 1/2 hp.
Still, that should be plenty power for mowing, as long as you don't lug the motor so the starting winding re- engages.
I have an old black & decker electric rotary mower.  18" cut.  On top of the deck is a plastic housing 10-11 inches tall and about 8 inches in diameter. One day I hit a branch with the motor housing and it popped off, revealing a universal brushed motor the size of a small hand drill.  It still mows grass, but it looks silly.

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Offline jonda500

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Re: Electric motor repairable?
« Reply #27 on: June 19, 2017, 09:56:01 PM »
Pulled it apart, found no evidence of arcing anywhere? The centrifugal switch opens the contact points which disconnects the start up windings when it operates.

It is a total mystery to me how these brushless motors work, googled the crap out of it and still none the wiser - maybe I'll cut the rotor open to see what's inside!

But I found the problem - the start up windings (yellow wires) have continuity, but the main windings (pink wires) are open circuited.

I think crompton parkinson probably still produce similar spec motors in the same dimensions as this one, but I guess depending on the price, it probably wont be worth it. I'll do some research and see...
Remember that an ignoramus is only someone who doesn't know something you just learned yesterday!

A starter clutch thread:
http://forums.sohc4.net/index.php/topic,122084.0.html
1972 CB500K1 original 4 owner bike
1972 CB500K1 returned to complete/original condition
1975 CB550F built from parts - project thread:
http://forums.sohc4.net/index.php/topic,149161.msg1711626.html#msg1711626
197? CB500/550 constructing from left over parts
1998 KTM 380 (two stroke) recent impulse buy, mmmm...

Offline strynboen

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Re: Electric motor repairable?
« Reply #28 on: June 20, 2017, 03:43:53 AM »
i have made a lot of this engines..takes a lot of time the first 4-5..but then you got a idea if the korrekt lenghts of both,the paper isolation and kobber vindings.. it takes the half time to do a stator..but most motors in Europa is the kondensator type..vho use both coil set at running kondision..so it give a better hp/vaight/cost..so ve only see this types in bowling machines..and specily made imported stuff..you can get a elektronic controller to skip the knickser ..but there is no idea to thange if it vorks..is this still sold/used in England aussie/us?..or is it antik..like in denmark
i kan not speak english/but trying!!
http://forums.sohc4.net/index.php?topic=60973.0
http://forums.sohc4.net/index.php?topic=144758.0
i hate all this v-w.... vords