Amp guage on briggs.

I have a 12.5 hp briggs & stratton and would like to put a amp guage on it. I have 2 guages, one off a very old wisconsin and another from a clark forklift. From the engine there is 2 wires from under the flywheel, for charging im sure, one is + one is -, correct? So how do I hook this guage up, or can I? Also do all I need to do is put the 2 wires on the battery post or do I need a regulator?

 

The wire with the doide inline is the charging wire. It goes to the battery post. The other wire is an AC voltage wire that connects to lights. Do not connect that one to a battery.

 

Where is this diode at? I never seen one.

 

Of the 2 wires, one should have a lump in it covered with black shrink wrap. That is the diode. It should be the red wire.

 

I found it, It was smaller then I thought and its hard to see in the dark barn. But why is the lights AC? And all I need to do is put this red wire in the + battery post? Thanks alot I really appreciate it.

 

Yep, just connect it to the positive post on the battery, or the solenoid, or wherever you have battery voltage when the engine is running.

The lights are AC because they don't have a diode or need one. The diode rectifies the AC current (which is a fluctuation of positive/negative/positive waves). The diode actually inulates the negative portion of the wave, so that you just get positive pulses. If you removed the diode from the charging stator wire, you would have AC current there too. You would also ruin the stator, because the diode stops battery current from making it's way to ground through the stator windings and turning them into smoke. It's like an electrical check-valve....it lets current go one direction, but not the other.

 

Im glad you told me this or I would have put the red on + and black on -. Then I would have tons of posts here wanting to know what went wrong.
Thanks alot.

 

This also explains (I think) why the lights get brighter as the engine runs faster, rather than using a relay to power them from the battery, they run straight off the magneto/generator.

 

You got it!

 

So the lights are AC????? Wow I learned something new. I always wondered how a snowmobile has a headlight but no electric start, I guess this is how. I did notice that snowmobiles light go dim and bright depending on rpm, I dont have a snowmobile so I dont know for sure. On the JD110 which is built in 1963 I think, it has a generator like a tractor and lights are DC.

 

Yup, the old delco generators that were used on the 110 series deeres were DC. Alternators are used now, on cars and lawnmowers. They actually make AC, but are then rectified to DC.