Alternator Issues - B&S 12HP

Hi all,
I removed the flywheel on my 12HP B&S Powerbuilt today, to find out why the alternator was only putting out 2 volts. I removed the alternator (snapped 2 of the 4 bolts though). I cannot see anything obviously wrong with it. Is there anything specific to look for when investigating this problem? Any help would be appreciated.

I don't know much about them. Just worked on a kohler V twin a couple days ago that wouldn't charge at all. They have a voltage regulator which I replaced along with the stator, which is what your talking about I guess, under the flywheel. I don't think briggs engines around the 12hp range have any kind of regulator though as far as I know. I would just find a another coil/stator/alternator. Probably has a wire shorted or something. I'm pretty sure they will fit from an opposed briggs as well. I think they're all the same size, in case you look for a used one.

I would find the proper ohm readings between a couple of different points i dont know what they would be or what they should read also make sure the magnets and contacts are clean
But thats what I'd do and Im no expert what so ever

Look at the steel part, looking for rust between the steel stacks (bad). Look at wire windings and insulator paper that keeps the wire off the steel(all paper needs to be there to insulate wire from steel). An ohm meter might give you a reading but will probably give you a no resistance reading which is useless. Need to visually look at the wire windings to make sure that the wire isn't shorting. If you look real close, it will be obvious. One wire coming out of stator means the other wire is grounded to the steel somewhere, check condition of the ground, maybe broke or corroded connection there. If ground wire is removable then remove it so it's not touching anything on that end and the output wire, make sure it's not touching anything, then use an ohm meter, touch one wire with one lead and the other lead to the steel to see if there is a reading, should be no reading, if there is a reading then the wire is shorting on the steel. Then touch one probe to one end of wire, and the other probe to the other end of wire(ground side) and should get a reading here(no reading means break in wire).

Thanks everyone. I will check those things, I do have a spare one somewhere.

Righto, checked the stator. I am getting a full reading with touching one end of the wire onto the live coming out of the stator and another wire onto the ground wire coming from the stator. However, if I touch two of the mounting holes for the stator with the wires from the ohm reader, I sometimes get a full reading, some times half, and sometimes nothing. So that is something that isn't completely right there.

MatthewD wrote:

Righto, checked the stator. I am getting a full reading with touching one end of the wire onto the live coming out of the stator and another wire onto the ground wire coming from the stator. However, if I touch two of the mounting holes for the stator with the wires from the ohm reader, I sometimes get a full reading, some times half, and sometimes nothing. So that is something that isn't completely right there.

If the ground wire is not connected to the steel or anything, then yes, the wire is grounding out in the windings. and is bad. If the ground wire is riveted to the steel, cut the wire off the rivet and pull it away so it's not touching anything and redo the test.

There is a wire that is bolted to the steel. I'm not sure if its a ground or not. But I did install a spare stator I had and hopefully this will solve my problems.

Yes, that was the ground. Ok.

When I get 5 minutes I will remove the ground wire and test it again.