Generator Field Coils Help

[Mayday53]

I am restoring the generator on the 55 KHK I am rebuilding. I see other options available as far as other generators, but I am staying committed to using all the original parts as much as possible. My genny is a model 52K and I need new field coils, bearings, and brushes. The brushes and bearings seem rather available, however, I am not finding the coils. Are there other model generator coils that are interchangeable with the 52K genny?

Any suggestions?

[thefrenchowl]

The coils part number, 30202-52, suggests they are a K only part. They were changed around 1958...

Patrick

[EKHKHK56]

Have you tested the coils? They usually don't require replacing in a rebuild unless bad. Erik

[EKHKHK56]

To test verify continuity through the disconnected coils which would identify breaks, and check for no continuity from coil to ground which would indicate a short. That's about it. Erik

[Mayday53]

@EKHKKHK56...I hired a generator electrician and he said the coils were covered in black soot and looked like they had been burnt up. The dilemma is that the guy I bought it from said it was running just fine, except for a leaky head, when he shut it down....25 years ago.

Are there any Generator rebuild kits out there, or do you have to pick and choose the parts individually?

[sean]

i found 2 52k coils recently on ebay ...number35 was the sellers name...i found the brushes at hd hummer

[hennesse]

@EKHKKHK56...I hired a generator electrician and he said the coils were covered in black soot and looked like they had been burnt up. The dilemma is that the guy I bought it from said it was running just fine, except for a leaky head, when he shut it down....25 years ago.
Are there any Generator rebuild kits out there, or do you have to pick and choose the parts individually?

The brushes slowly wear down and the carbon particles (black soot?) really have nowhere to go but inside the generator. A spray can of brake cleaner should get the soot out.

The field coils seldom go bad unless you have done something really, really bad to the generator. I've never had a generator with bad fields. I would not mess with them unless you know they're bad. And getting the screws out of the pole shoes can be almost impossible.

As Perry Ruiter notes over in the Technical:Generator section, it matters which wire goes where, so be careful to mark the wire positions as you disassemble. If you really want a professional rebuild, contact Perry.

You can do a quick check on the coils with an ohmmeter with the coil wires unattached to anything. From one wire end to the other wire end should read something small, maybe like 1 ohm - if it reads infinity, it's got an open. From one wire end to the generator case should read infinity - if you get a reading other than infinity, it's shorted.

The real test requires a 6v battery and ammeter. The current flow through the coil should be 0.9 to 1.1 amp as noted over in Technical:Generator. But if the ohmmeter test comes out OK, I wouldn't even bother. Clean the thing up, replace the brushes and bearings, clean up the commutator, and put it back in the bike.

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The model 52 generator is a 3-brush generator that was used on big twins starting in late 1952. It uses the same 30202-52 field coils as your 52K (which happens to be a 2-brush).
Try here: http://www.45restoration.com/Products/F ... 02-52.aspx
But I wouldn't mess with them unless you know they're bad...

[Mayday53]

Well, I had the generator rebuilt. The technician said a seal had gone bad and the the field coils were grounding out to the case. However, he replaced the coils, cleaned up the armature, put in new bearings, new seals, and rewired it for less than $200, which seemed reasonable.

Thoughts?