Generator question

[Go Fleiter]

got some useful advice at the P15D24 forum.
I had to reface the regulator´s contacts and settings and the generator´s brushes.
My spare generator, new since it´s production, just needed to be polarised
to perform perfectly withn the same regulator.
Greetings from sunny Düsseldorf!
Go

[Go Fleiter]

Hi all,
  please: how can I distiguish generator bug from the voltage regulator´s?
  I lost battery loading capacity and changed the very consumed generator brushes.
When put back, problem was not solved. I suspected the brushes not having goog axial pressure on the collector- have to check.
  When disconnecting the battery, engine stalled before, now continues running, but only if running at ~1000 rpm.
Then I put my spare generator- fresh [10 years ago :) ] from Bernbaum´s.
It does load, but just up to 6.5 Volts instead of the 7.3... V as expected.
Engine however does not stall any more with batt off.
  Voltage reading on both generators was around 1 Volt with no connections to the regulator, not changing much up to 2200 rpm.
Question:
1.) is the low reding on the unconnected generator ok?
2.) is it safe to connect the field wire (the smaller one) to the generator and may I get a valuable voltage reading informing me on the pure generator performance without including the performance of the voltage regulator?
I remember having had 20-30 V readings on bare generator, but I don´t remember und which circumstances.
  Is there a method to tell generator defct from regulator defect or is it a trial and error matter?
Thanks for Your hints!
Greetings from Düsseldorf!
Go