A generator needs "residual magnetism" to be able to develop a voltage. If it's mounted on the engine with the wiring connected, make a momentary connection with a jumper wire between the regulator wires, "Bat" to "Arm". There should be a pretty noticeable arc when you connect, so only leave it connected for a moment. Once it's polarized, the "arm" terminal on the generator should produce about 1/2 volt or so with the generator turning and all the wires disconnected. Once you find that the generator can produce residual voltage, reconnect the wires and attach a jumper wire from the "F" terminal to ground. The voltage at the armature terminal should rise without limit as the engine speed is increased. Don't go much above a fast idle, as high voltage output can damage electrical accessories.

If the generator can produce voltage by grounding the field terminal and it still doesn't charge the battery, the voltage regulator or cutout relay in the regulator assembly could have problems.
Jerry

P.S.: Check out the article I put in the tech tips for some quick and dirty basic training on DC generators!
Jerry




Last edited by Hotrod Lincoln; 09/07/2010 3:48 PM.
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