On Sun, 24 Oct 2010 21:42:27 -0500 Dieselhead <126die...@gmail.com> wrote:
> Wiring diagram: > http://s101.photobucket.com/albums/m46/farmallbob/Farmall%20Tractor%20Wiring%20Diagrams/?action=view¤t=03-6Voltcutoutanddistributor-rev-1.gif > (doesn't show the internal workings of the 4 position switch) > > This has a diagram of the 4 position switch. > http://www.tractorshed.com/cgi-bin/gallery/pieces_pic.cgi?pic=http;//www.tractorshed.com/gallery/pieces/p50454.jpg&firstrec=1&lastrec=15&Parameter=&mode=All&what=pieces > > SO: what I get out of this is that high charge grounds the field. > so if I ground the field, there should be no damage at low-med engine > RPM. The first link's schematic shows no way to ground the field directly. Something is wrong here, but I cannot tell you if it's the first link or the second link. > AND: It appears that the battery can be connected to the armature. My guess is that the cutout relay is energized by the generator and pulls in to connect the generator to the battery when the engine is running, working like a mechanical diode so the battery doesn't discharge through the generator when the engine is not running. > ONE OTHER THOUGHT: Somewhere I heard years ago that you can turn a > generator into a motor by hooking up the + and - a certain way. Does > anyone now how to do that? Hook the field up so it is powered by the battery and hook the armature up to the battery and it should spin. > I could easily test the loose generator that way. and even the one on > the engine should make a noticeable effort to turn the engine over. > (for a second or so.) Given that it's intended to do the reverse and doesn't have the mechanical advantage a starter does, I would expect there to be no visible indication the generator is trying to turn the engine. Try this: Disconnect all wires from the generator and measure the resistance from the field terminal to the frame of the generator. Then measure the resistance from the field terminal to the armature terminal. One of the measurements should have a higher resistance (though maybe not by much). A generator, as used in these applications, has to have a residual magnetic field in the field winding's core in order to start generating. If that residual field has been lost, the generator will not generate. You will need to "flash" the field with a battery (a momentary connection to magnetize the field's iron core). http://www.engineersedge.com/motors/generator_field_flashing.htm http://www.generatorguide.net/howgeneratorworks.html Craig _______________________________________ http://www.okiebenz.com For new and used parts go to www.okiebenz.com To search list archives http://www.okiebenz.com/archive/ To Unsubscribe or change delivery options go to: http://okiebenz.com/mailman/listinfo/mercedes_okiebenz.com
