That is not the way to test the rectifier.
The 2 wires that are the same colour are the AC feed wires and are connected to either side of the stator windings
The single wire in the middle is the DC + feed back to the battery
The body is ground.
You check OHMS between the AC & DC connections .
You should get continuity one way round and no continuity the other way round because the rectifier is just a bunch ( 4 to 6 ) of diodes.
So you start by checking the AC out put from the stator plug.
You should see between 24 & 40 V AC between the two wires & 1/2 that between either one and ground.
After that check the DC voltage from the middle terminal to ground.
If it is 12.5V or better then all id fine & the problem is in your wiring
The most common problem a bad ground contact between the body of the rectifier & the mower.
After that it is a bad connection on the + wire between the rectifier & the battery ( usually the switch )
Per AVB's request...here are photos: Sorry...the iPhone wouldn't focus on the close up that has the part number:
I tried to make sense of the parts manual numbers and what part supersedes other parts...very difficult.
I've double checked and the part number on the regulator is 808294...promise. And, below it just a bit and to the left is this number: 2214
Thanks ILEngine:
I agree that the parts manual shows my part number as 847385: But, then when you call it up, the photo does not have the same connectors and will not work with my engine. The part that does match is Part No. 691573. This looks the same as the part off of my engine; but, I'm concerned that it doesn't match what the parts manual says.
Bert, I looks like for some reason that this guy has the unlisted third option. He has the three wire white flat connector with barrel wires. The two regulators that they list for his engine are either a two wire flat spade black connector with a single red wire, or two 2 wire flat connector with barrel end wire connectors, plus a single red wire connector.
other than a small handful of big block Vanguard engines it looks like his regulator was used on 18 hp and smaller engines.
Thank you very much for this information.
In summary it appears that the conclusion is that Part No. 691573 may replace the part I actually have on the engine; but, 691573 may be the part for a smaller sized engine. I'm thinking this may be why the regulator won't keep the battery charged. So, I want to fix the problem...what can I do to put a regulator/rectifier on the engine that will properly charge my battery?
Is there any way to rewire the connector so it will work with the correct 847385 regulator?
Thanks again for any help you can provide.
P.S. Why is B&S so clueless when it comes to helping the consumer with problems such as this....it is there product and I couldn't get anybody to help me.
The power output is a function of the size of the magnets in the flywheel and the windings in the stator and most important the speed of the engine.
If you are not runnig full speed then the alternator can not generate the full rated power.
I had a customer who would only run his mower at 2/3 speed to "reduce the wear on the engine" I found this out after I had replaced his battery 3 times in a single season.
I could find nothing wrong with the mower & did the last replacement on site then watched him mow for a few minutes.
The listed regulator output is what the regulator can handle.
Changing the regulator will not change the output
What does happen is the magnets can come loose in the flywheel and that also makes a drastic reduction in the output of the alternator.
Now the burning question is
Have you owned the mower since new ?
What engine work has been done to it.