6 volt or 12? The same diagnostic procedures apply either way, but the result numbers will be different. The flickering no charge light probably means the cutout relay in the regulator is opening and closing for some reason, possibly dirty points on one of the regulator coil contacts.

Disconnect at least one battery cable, and remove the top of the regulator. It's usually held on with two small sheet metal screws. There will be three sets of coils inside, one with a large set of points that will be open with the engine off. The other two sets of points will be held closed by a small coil spring. Take a clean piece of file card stock or a business card, and gently rub it between all three sets of points, changing positions frequently to expose clean areas of the paper. DO NOT use any type of sandpaper or a file! Once all the points have been cleaned, crank up the engine and observe the operation of the points. The normally-open set (the cutout relay) should snap shut as soon as the engine starts, and the idiot light should go out and stay out. If you gently push either set of normally-closed points open, the cutout relay will snap open and the dash light will stay on. As soon as you release the held-open point, the system should go back to charging.

Any operation other than point cleaning inside a regulator should probably be left to someone who is thoroughly familiar with generator/regulator system adjusting. We're getting to be sort of a dying breed! It's possible to adjust the air gaps on the point assemblies, the closing voltage on the cutout relay, and the current and voltage limiting points, but it takes a couple of special meters, and a tool or two that some shops don't have. As a matter of safety, it's always a good idea to at least remove the Battery wire from the regulator, or to take one of the cables loose at the battery before installing or removing a regulator cover. One slip, and some nasty shorts and permanent damage to the regulator can happen.
Jerry

Edit: It'd s possible to check system operation with a discharged battery, but it's better to do any adjusting other than setting the current regulator against a fully-charged battery. it's possible to get some really off-the-wall voltage numbers if the generator is running at its full capacity to recharge a low battery.
Jerry

Last edited by Hotrod Lincoln; 11/05/2008 6:33 PM.
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