[Mg-mmm] P-Type Dynamo.

[Gerald Felper]

Jason
The third brush is connected to one field wire and the other field  
wire is connected to the F terminal. Both the third brush and the two  
larger brushes positions are adjustable. Moving the third brush in  
the direction of rotation increases the current. With the field wires  
open check to see that they are not shorted to the case.
Jerry

On May 2, 2009, at 8:03 PM, jay at ukhistoric.com wrote:

> Back working on the dynamo.  Received the new brush set and installed
> after cleaning up the unit.  I did not yet open up the unit, though.
>
> I have a few questions on the positions and connections of the  
> brushes:
>
> 1) Is the 3rd brush, the thin one, opposite from one of the large  
> brushes??
> 2) Is the 3rd brush supposed to be connected to the field coils  
> which is
> then connected to the smaller external connection on the body?
> 3) One of the large brushes is connected to ground, the other is  
> connected
> to the large external connection.  Is this correct??
> 4) Large brushes are about 90 degrees apart.  Correct??
> 5) The commutator seems to be in good shape, but I have not checked
> resistances between "slices".  Should I be measuring adjacent,  
> opposite,
> or others??
>
> There does not seem to be any shorts or "opens" between connections
> externally and internally.  I need to recheck resistances - one
> measurement is 7 ohms, the other around 225 ohms.
>
> I've found various docs online, but none seem to match my current  
> internal
> configuration.
>
> Thanks!
> Jason.
> P1237.
>
>> Hi all!
>>
>> Working on solving a dynamo problem on a P-type, PB engine.  Unit  
>> does not
>> seem to be charging.  I removed the dynamo from the engine and  
>> found that
>> due to oil and grime build-up, the brushes were frozen in the  
>> holders.
>> While removing the small third-brush, I managed to break it.
>>
>> So, a few questions:
>> 1) Is there a US source for a set of brushes?  Any generic part  
>> numbers I
>> could even give to my local rebuild shop?
>> 2) Should the unit be dismantled to clean?  Remove the crank  
>> gear?  Any
>> other tricks to opening the unit?  Or just leave alone and clean  
>> the brush
>> holders as best as possible?
>> 3) Can the third brush be adjusted on the bench?  I needed to move  
>> it to
>> remove the brush but marked the original position.  Or just follow  
>> the
>> adjustment procedure once back on the car?
>>
>> Thanks!
>> Jason.
>> P1237.
>> _______________________________________________
>> Support Team.Net http://www.team.net/donate.html
>>
>> Mg-mmm at autox.team.net
>> http://autox.team.net/mailman/listinfo/mg-mmm
>>
>> You are subscribed as jay at ukhistoric.com
>>
>> http://www.team.net/archive
> _______________________________________________
> Support Team.Net http://www.team.net/donate.html
>
> Mg-mmm at autox.team.net
> http://autox.team.net/mailman/listinfo/mg-mmm
>
> You are subscribed as felperg at earthlink.net
>
> http://www.team.net/archive

Gerald Felper
Felper Engineering
felperg at earthlink.net