generator not charging _ How come?
 

Working on A with charging system issues. Has newly rebuilt generator with NuRex solid state cut-out. With motor running, not charge at ammeter, Does, however, show discharge if you turn on lights ( ammeter OK). With motor at idle, I place jumper across cut-out and now have charge of 10 amps. I remove jumper and still +10 amps. Shut of motor, restart and no charge. Re apply jumper and once again +10 amps. Go for a drive and shortly after leaving garage, charge is lost and ammeter falls back to zero. Have tried two new cut-outs which test OK for current flow and direction. I'm kinda lost. any ideas?

Re: generator not charging _ How come?
 

What type of cut-outs are you using ? Any originals ?

Sounds like the problem is with the cut-outs.

Loosen the fan belt, apply power to the generator and see of it tries to motor. If it does motor, or tries to, that leads me to bad cut-outs.

Re: generator not charging _ How come?
 

Call NuRex???
Paul in CT

Re: generator not charging _ How come?
 

Are you sure thats a solid state cutout ? Sounds like normal operation for a fun projects regulator. Will only charge if battery needs it. However, shorting across a voltage regulator is not a good thing.

Re: generator not charging _ How come?
 

So, you are using a diode cutout with correct polarity, but the generator looses it's magnetism.
Who rebuilt the generator, and are the pole shoes tight to the body, and what is the air gap from the armature to the pole shoes?
I had an armature that tested good, but someone turned the armature to remove rust, and this made the air gap too great to give good output. It operated similar to what you have going on.

Re: generator not charging _ How come?
 

My generator wouldn't charge so I did what any of us would do, I took it apart. It was filthy inside with dirt and rust. I had a brass wire wheel in a drill and it fit almost perfect inside the housing to clean the plates and I did the same to the armature. I scraped out between the gaps on the small end with something plastic but sharp. Cleaned and lubed the brush holders. Put it back together and learned what the third brush does. I looked for any burnt or black spots and found none. I found it would motor after I cleaned it. It works great now. I know this doesn't help the poster but it may help someone else as they search.

Re: generator not charging _ How come?
 

UPDATE. Tried 2 solid state (NuRex) and 3 original type mechanical cut-outs. All with same result. No charge unless I placed jumper across cut out. Generator was recent rebuild by reputable rebuilder in NE Ohio. Removed and inspected generator. Found one brush was not contacting commutator at all and the commutator surface was contaminated with a black tar-like mess. Rebuilder gave me another generator. Installed and all is well.

Re: generator not charging _ How come?
 

Its always nice to hear the results. Glad the 'rebuilder' made it right.

Re: generator not charging _ How come?
 

Have you check all three brushes for free movement/contact?