re Chris K's generator troubles...
I have had similar troubles, and helped others with them...
experience says the trouble is typically not where I think it
is during the first few tries. Here's some thoughts:
-field coils are typically 4 ohms, they are probably ok if
they measure anywhere near that.
-I saw the trouble with the cutout not cutting in once...
the shunt coil was gone, but the series coil would hold
it in if you pushed it by hand... but you say the shunt coil
is 50 ohms, about right. Are you sure you are not measuring
the shunt coil for the voltage control rather than the
cutout? they are in parallel from "D" (dynamo) terminal
to ground?
-I have many times tried the "join dynamo and field, rev engine
and watch voltage". Twice have rev'd too high: 1. suddenly
say 100V appear, then the armature shorted internally. 2. had
the battery connected, saw 30V and then the current surge
melted the brush wire!- at least that fix was cheap. (Both
times the real problem was the regulator, not the generator).
-have also seen intermittent generator problems: check for
-brushes somewhat worn and gummed up, sticking in holders.
-armature arcing has made some commutator segments rough.
(Best to turn down slightly in lathe, but have also
had good success with fine sandpaper. Do not use metal
grit paper).
-one other test to try: "motoring" the generator. Join field
and dynamo, remove fan belt, and apply 12V (from battery or
charger of at least 5-10amp capacity. Charger will at least
avoid possibility of destructively high current). Generator
should spin along nicely. If commutator contact is intermittent,
a quick spin by hand may get it started, thereby confirming
diagnosis.
Good luck...
Dave Agnew
crm24@bnr.ca
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