Armature from one generator, field windings from another... what are the odds of it working?

If all the parts come from VW/Bosch 12V generators this should work.

OTOH, how did you test these? There's several reasons why the output might vary and "weak" field coils is WAY down on my list.

I would test field windings with an Ohmmeter. Just measure between the D+ and the DF terminal. They should measure about 4 Ohms, I think. lower indicates shorted turns which are bad. Infinity indicates a broken wire somewhere.

My impression is that "weak" is a word that would be used to describe a field coil only by someone who didn't understand generators.

----------------------------------------------- Jim Adney snipped-for-privacy@vwtype3.org Madison, WI 53711 USA

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Actually, I took more of the "folk" approach to testing than analyzing the design of the generator. Yes, I have studied transmission lines/delta-wye circuits/transformer theory/etc... I was following a less scientific approach based on what the power O/P characteristics were. My one generator produces wildly fluxuating voltages. The other is consistently low in its O/P (it HAD been my good one).

Changing output would indicate that something inside was changing, generally a connection of some kind. The first things I would check would be to make sure the brushes aren't worn too short (they should stick out of the brush holders a bit) and that you don't have a break in any of the wire leads that are soldered to the underside of the D+ and DF studs. These can break if the studs are allowed to turn when you're tightening or loosening the wires connected to them on the outside.

Then make sure that the little screw that is visible in the END of the generator is still there, and tight.

----------------------------------------------- Jim Adney snipped-for-privacy@vwtype3.org Madison, WI 53711 USA

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