Basic voltage regulator question

[gr8shot]

My Scag is a repower with a 27hp briggs professional engine. No real problems other than the voltage regulator isn't hooked up to the battery, so it doesn't charge. Just want to confirm how it should be hooked up. It has a 3 wire regulator. Google has learned me that the two yellow wires go to the alternator, which they appear to be hooked up to already. I'm assuming that the red wire needs to be hooked to the battery to charge it? It's not hooked to anything right now. I can mow 3 or 4 times then the battery will get weak and I have to charge it. And if i use a sprayer or the lights I hooked up, it'll kill the battery pretty quick.

Any help would be great! Thanks!

 

[bertsmobile1]

Yes it should be connected to the battery.
The wiring diagram should be in your owners hand book.
Sometimes a diode goes open circuit in the rectifier which will flatten the battery , dead so some people disconnect it when they have finished mowing.
You should see around 30 V AC between the 2 yellow wires with the engine running at full speed and 12 V DC between the center wire and ground.

 

[gr8shot]

I think it was just never hooked up after the repower. I bought the mower right after a shop did the repower, and they said the new motor had about 2-3 hours on it was all. So I'm guessing it was just an oversight when they installed the motor. I'll test it with the multimeter and as long as all is well I'll hook it up and see if it takes care of my lack of charge. Thanks!

 

[Mad Mackie]

What was the original engine?
A few things to check:
Make sure that the rectifier/regulator is connected to the engine stator output, two pin connector with yellow wires.
Make sure that the rectifier/regulator output is connected to the engine harness.
Briggs uses a six pin engine adapter harness, but only uses four of the six pins. Sometimes the charging system output pin needs to be relocated to another slot to connect to the Scag side of the engine harness connector.
Check the 20 AMP fuse in the fuse holder with the yellow wire. This yellow wire brings the charging system output to the key switch, where when the key switch when in the on position allows the charging system output to flow into the electrical system and to the battery.

 

[gr8shot]

Not sure what the original engine was. I really never got a history on the mower. My dad found it for me and was in the area so he tested it out and thought it was solid, so I gave him the money and he picked it up for me too. I didn't get a owners manual or any history with it.

I think everything else seems to be in order, the key start works like it should, clutch for the deck works right, and all the safety switches work right. So I think they just forgot to hook up the output from the voltage regulator to anything. The two yellow wires are hooked to the stator, it's just the red wire thats hanging free not hooked to anything.