brush wires on alternator - Fiesta

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Sat 17 Mar 2007 11:46
brush wires on alternator - Fiesta - milkyjoe
hi, i took an old knackered alternator to bits to examine the contact brushes,the wires they are connected too looked very thin and brittle, they hardly look capeable of passing a lot of ampage ,can they be replaced ,its off a fiesta?
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Sat 17 Mar 2007 12:50
brush wires on alternator - bell boy
not worth the effort
im tight and even i would buy a replacement
eurocarparts sent me a flyer this week ,£45 plus vat all brand new reconned
why get the smouldering iron out?
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Sat 17 Mar 2007 12:54
brush wires on alternator - kithmo
Certainly not worth soldering new wires on, but going back 20 years or so, if you can still buy them, new brushes used to come with the wires, spring and connecting plate already on and were only a couple of quid then.
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Sat 17 Mar 2007 12:56
brush wires on alternator - kithmo
Further to the above, IIRC you could also buy a "brush box" for some alternators, which was a bolt on affair with the brushes mounted in it.
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Sat 17 Mar 2007 12:57
brush wires on alternator - Fiesta - Screwloose
MJ

Fiestas have had dozens of different makes and types of alternator over the years - which is yours?
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Sat 17 Mar 2007 14:54
brush wires on alternator - Fiesta - milkyjoe
types of alternatorover the years - which is yours?


magnetti mirrelli i think
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Sat 17 Mar 2007 15:28
brush wires on alternator - Fiesta - Aprilia
The wires only carry the energising current to the rotor - not the output current!
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Sat 17 Mar 2007 15:41
brush wires on alternator - Fiesta - milkyjoe
oic, so the output wire is connected to the 3 phase coils which are static then? that makes scence now,cheers
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Sat 17 Mar 2007 21:54
brush wires on alternator - Fiesta - Aprilia
oic, so the output wire is connected to the 3 phase
coils which are static then? that makes scence now,cheers


Indeed. Output is from the stator winding (3-phase) and rectified.
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Sat 17 Mar 2007 21:59
brush wires on alternator - Fiesta - Screwloose
MJ

Magneti-Marelli make many different types of alternator. If it's the most common, the A127, [there should be a label on the side with numbers] then the brushes are in the cast-alloy regulator on the back which has one internal plug and is held in with three long 4mm screws.

The whole reg is dirt cheap and can even be changed in-situ.
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