30-03-2019, 01:30 AM
The resistance wire only affects Summer charge. If failed will be none. As above, Sounds like worn, stuck or oily brushes.
The contact points are silver and should not be abraded with anything that might embed. If must be trimmed a clean fingernail file applied very gently ideal.
As previous posts the basic test of a dynamo is to isolate, link F and Output and connect an old 12v headlamp bulb between the link and earth. The bulb should glow fully at lowish rpm and get very bright as revs increased. if you have an analog meter should show 6v at revs below normal cut in revs, and exceed 12v at gentle engine revs.
Such antics often safer with the fan belt off.
The contact points are silver and should not be abraded with anything that might embed. If must be trimmed a clean fingernail file applied very gently ideal.
As previous posts the basic test of a dynamo is to isolate, link F and Output and connect an old 12v headlamp bulb between the link and earth. The bulb should glow fully at lowish rpm and get very bright as revs increased. if you have an analog meter should show 6v at revs below normal cut in revs, and exceed 12v at gentle engine revs.
Such antics often safer with the fan belt off.