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I bought a 1992 John deere 320, ignition switch was out, so I replaced that, got it running, have continuous battery light on, reading 12.63 volts on battery, same while running, I disconnected harness from regulator, battery light goes out, tested voltage through harness where it connects to regulator, it reads the same. can anyone give me any input on this?

Just to clarify - you checked the voltage coming out of the stator but before the regulator? Or you tested voltage out of the regulator? If the former, and you're only seeing about 12 volts, then yes, something in the stator is going bad and it's not generating enough voltage to keep the battery charged. On average you need to see at minimum 13.5 volts to charge a 12 volt battery. If you've got accessories - such as headlights - you should be seeing 14.5+ volts because otherwise the battery wouldn't be getting charged or the headlights wouldn't be running at full capacity.

But keep in mind - this is after the voltage has passed through the regulator. As its name suggests, it's supposed to regulate the amount of voltage leaving the stator to prevent over charging the battery and frying wires, therefore I'd expect to see at least, if not more than, 15 volts leaving the stator before entering the regulator.

To make it a little easier: pre-regulator you should see at or above 15 volts -- post-regulator you should see no less than 13.5 volts.

I should also point out that I'm not a lawnmower expert, but I am an auto mechanic and the same principles operate both systems. The difference is going to be in the actual numbers and whether or not the stator on your mower is supposed to generate that much voltage - it could be more or less. But even so, you should see more than 12.6 volts to charge the battery.

ok, so I tore down top of motor(radiator) and that plastic shroud off, figured out which wires are the stator wires, and which harness they go directly into, I probed the backside of the wires going into the harness, if I put it in dummy mode and just turn motor over without starting its around 5v(ac) and if I let it run on almost full throttle I'm getting 2.5 to 2.8v(ac) on my meter.

Please post the engine model numbers, that way we will know which charging system you are dealing with.

Model is kawasaki fd590v

This manual has a great procedure for testing the charging system on your engine.

http://www.mymowerparts.com/pdf/Kaw...90V-FD611V-KAWASAKI-SERVICE-REPAIR-MANUAL.pdf

spepple1989 said:

ok, so I tore down top of motor(radiator) and that plastic shroud off, figured out which wires are the stator wires, and which harness they go directly into, I probed the backside of the wires going into the harness, if I put it in dummy mode and just turn motor over without starting its around 5v(ac) and if I let it run on almost full throttle I'm getting 2.5 to 2.8v(ac) on my meter.

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Is your meter auto-ranging or is this a typo? Because it makes no sense for you to be getting 5vac turning the engine over by hand, and only 2.5-2.8vac at full throttle. Did you mean 0.5vac when turning it by hand? It's a pretty basic principle - the faster you move the armature through a coil of wires, the greater the voltage generated.

If, however, your meter is auto-ranging (or you didn't have it set correctly because I'm not sure what you mean by "dummy mode") then it's probably 5vac turning by hand and 25-28vac at full throttle.

You need to clarify which readings you're getting. According to the manual Rivets linked you to, you should be seeing 26vac unregulated output (before the regulator) at 3,000 RPM (which I'm guessing is full throttle).

ok, so here's an update, I bought a used stator cheap to do some testing, while I was at it, I cleaned the inside of the flywheel, was dirty and gummed up with dirt and dust and grass. out of both stators I'm averaging 8.5 volts. my ohm reading on both is .4 to .5, which by the book is too high from what I understand.

spepple1989 said:

ok, so here's an update, I bought a used stator cheap to do some testing, while I was at it, I cleaned the inside of the flywheel, was dirty and gummed up with dirt and dust and grass. out of both stators I'm averaging 8.5 volts. my ohm reading on both is .4 to .5, which by the book is too high from what I understand.

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When you measured stator resistance, was it unplugged from the harness? A must for accurate continuity (resistance) checks is the circuit has to be dead. Even a static (residual) voltage can throw off the resistance. You can discharge a residual voltage by connecting a test lamp between the stator pins in the connector. Also, was it still warm from the engine operation? Heat adds resistance, so that can effect your readings also.

When you had the flywheel/stator assembly apart, did you check the integrity of the reluctor wheel? It should be mounted under the flywheel and inside the stator - it's what would be rotating within the stator to generate the voltage. It should look like a gear with small, stubby teeth. Broken or missing teeth, or if there's a crack in the wheel (from the manual, it's not clear to me if the reluctor wheel is machined into the flywheel or if it's press fit) can cause low and/or inaccurate voltage generation. The stator magnets need to have a constant rotation of the reluctor wheel teeth to generate steady, strong voltage. Even the smallest of cracks or chipped or missing teeth can bring the whole system down.

You may be getting frustrated at this point, but keep updating us (pictures help too, if possible) and we'll keep guiding you through it. And if necessary, walk away for a while - sometimes even a 10 minute break can do wonders for keeping your head level. :thumbsup:

ok, I won't have any time til this evening to pull it apart, but yes the stator was disconnected when I checked resistance, and the motor was cold, had not been run at all. however I didn't try putting a incandescent light bulb on it to try. and I'm not sure if I know what you're talking about with the reluctor wheel and gear, but I will pull the flywheel and inspect and try to find this.

spepple1989 said:

ok, I won't have any time til this evening to pull it apart, but yes the stator was disconnected when I checked resistance, and the motor was cold, had not been run at all. however I didn't try putting a incandescent light bulb on it to try. and I'm not sure if I know what you're talking about with the reluctor wheel and gear, but I will pull the flywheel and inspect and try to find this.

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Don't worry about the test light on the stator - if the motor hasn't been running recently it's nothing to concern yourself with. At best a static charge will hold for 30-40 seconds after shutdown.

Regarding the reluctor wheel: according to the manual Rivets linked you to, the flywheel doubles as the reluctor wheel (see page 7-10, it's referred to as the "Alternator Rotor"). What you want to do is remove the flywheel and inspect the side of it that doesn't face up/out when it's installed. If it's a cupped/concave flywheel, you want to look at the concave side. You should see 1 of the 3 following configurations (the pictures in the manual aren't very good otherwise I might be able to tell you exactly what to look for):

1) There will be internal-facing teeth on the outer rim of the flywheel (most likely set up), or

2) There will be external-facing teeth around the center bore of the flywheel.

3) There's a magnet(s) mounted on the flywheel.

Regardless of whether it's magnets or teeth (or a combination of both), the principle is the same - as they pass by the coils of wire on the stator, voltage is generated within the coil which is then fed to the regulator. If there are any defects in the stator or the teeth (or magnets), it will not work as efficiently. All you need to look for are obvious defects that would cause the faulty operation - cracks, broken, chipped or missing teeth (or magnets).

I pulled the flywheel back off, flywheel looks brand new underneath. nothing looks wrong at all, heres a picture of the stator. 8.8v(ac) reading coming directly from stator.

It looks like you have a couple of coils there with darker wires than the others. This is a sure sign of excessive heat exposure and wiring that is "worn out" (for lack of a better term). There does need to be some accounting for age & use, but basically, you want to see a relatively bright sheen on the copper. Is the other stator you bought in similar condition?

Also, do you remember when you first took it apart if there was an oily film on the stator and flywheel? It looks like the oil seal might be leaking, and if so, the rotation of the shaft may be throwing oil all over the stator and flywheel - that's going to cause a lot of uneven heat distribution when the engine is running. It likely won't cause immediate problems, but over time it will wear out the stator.

Have you checked the stator(s) for short to ground? With your meter set to ohms, place one lead of the meter on one of the connector pins and the other lead on the steel ring in the middle of the stator (where the screws thread through). In theory a short to ground will cease all output of the stator, but electricity can do some really funny things, however unlikely they seem.

My final piece of advice would be to buy a new stator. It seems likely the stator is the source of the problem, and the used one you bought was simply as worn out as the one you already had.

Here's a video that goes into a decent amount of detail regarding small engine stator operation and testing. It's not a Kawasaki, but again, the principles are going to be the same:

https://www.youtube.com/watch?v=G_7FD_ZhKSg

Yeah I did discover the main oil seal is leaking today as well, I already have one ordered. Also, that's what I've been thinking the whole time is the bad stator, the original one is really dark as if the leaking oil coated itself on there, or it just got really hot which is what it appears to have happened.

Did you get the new stator, and if so, did it correct the problem?

I have one on the way, should be here Friday or Saturday.

well I got a new one...connected to stator I had over 30 vac while running full speed. I didn't run to long due to not having coolant in motor from radiator being torn down but my dc voltage on battery, the last reading I got was 13.33 volts and rising steadily. Battery light is still on but I assume that's because the charging voltage post regulator hadn't gotten high enough to shut it off?

spepple1989 said:

well I got a new one...connected to stator I had over 30 vac while running full speed. I didn't run to long due to not having coolant in motor from radiator being torn down but my dc voltage on battery, the last reading I got was 13.33 volts and rising steadily. Battery light is still on but I assume that's because the charging voltage post regulator hadn't gotten high enough to shut it off?

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It's probably b/c the battery was run down from the old stator. Do you have a charger? If so, give it a complete, low amp charge (ex. my charger is 10 amps max) and it should be fine. If you don't have one, leave the mower to run for 20-30 minutes and give it a good charge.

If that still doesn't shut it off, it's possible there's something wrong with the battery light circuit (bad ground, shorted wire, etc), but seeing 13.33 volts @ the battery is great - it means you didn't buy a brand new stator for no reason. :thumbsup: