Measure the Voltage across the battery at high engine speed. You should have around 14ish VDC.

If it's around 12.5 or less, it's not charging.

Thanks Bill. When running at full speed it is 5.8V. Any thoughts on what needs to be replaced? Stator?

5.8V sounds like the battery is BAD or VERY discharged.
Briggs has multiple types of charging systems, but I'll ASSume this one has a Voltage regulator instead of a charge diode.
The VR would be a "squarish" box. It would have 2 YELLOW (or possibly BLACK?) wires coming from the stator going to it, with a 3rd RED wire coming from it to supply the system.
Disconnect the connector and measure the AC voltage between the YELLOW wires. It should be something like 28-40 VAC minimum. IF not, stator or flywheel (magnets) is bad.
If this doesn't describe your system, let me know-
What color wire(s) are coming from the stator AND the color of the connector on the stator.

Thanks Bill - I thought I sent a resposne but it doesnt seem to have posted. There is a square box (regulator) attached to the stator wires. There are 3 wires 1 red (with a mid point connector) and 2 black wires from the stator with a yellow connector. The yellow connector then has 2 yellow wires running to the regulator.

When I measure the VAC at the connection - it was 22VAC (measured on the pins at the stator side of the connector). I had to keep the booster battery attached or else the machine would stall (any impact from this). The battery is completely drained so I needed to keep it attached to meausre the VAC.

Thanks again for your help..

OK-
There are 2 different capacity systems like you describe!
One passes and the other fails your initial stator test-

We need to dig a little deeper to identify. These systems were used in different years (according to my info) so I'll need the CODE off the engine.

Give me the Model & Type (to make sure I'm looking at the right IPL- I show a Model 406577 Type 0139) AND CODE.

Does the owners manual possibly specify the AMPs of the system? 10, 13, 16 etc?

I'm using this link for engine ref-

Here is a link that might be useful: Link

Thanks again Bill. You have the correct model and type. The code is 041217YG.

The manual specifies the AMP at 16 for the L111.

The 16A alternator should have 30 VAC at the stator leads.
You did have it disconnected from the VR didn't you? And AC, not DC?

I guess the good news is the new stator coil is about $27, while the VR is about $73!
Stator PN 696458
VR PN 691185

As a check, you might try hooking the VR back up, but disconnecting the RED wire somewhere in the circuit. Measure the RED output of the VR, DCV,to confirm that something is bad. Maybe even hook up a 12V light to add some load??

When you remove the flywheel, inspect the magnets to make sure you haven't lost one. I'd do that before buying any parts, just in case.

Definitely had it disconnected from the VR. And AC not DC. It also tried your suggestion of reconnecting the VR and disconnecting the red wire. the output(red wire) was 1.8 DCV. Does that still make sense?

Sounds like the alternator is toast!
The VR isn't going to produce the desired 12+ VDC if the input to it is "garbage".

As a final check, you might try a 12V light bulb to the 2 yellow wires. IF the alternator is putting out enough, it should blow the bulb, or at least be EXTREMELY bright. IF not, then obviously it's not putting out useful current. It should be capable of 200+ Watts!

Something else you can try "for grins" is (with the connector unplugged) check the ACV from each BLACK/Yellow wire to ground and see if they "match". IF they are very different, I'd definitely condemn the stator. Each one should be showing 15ACV minimum.
Just curious about that result????

I would definitely say the stator is bad, IF the flywheel magnets are intact.

Bill. Thanks again for all of your help-it has been much appreciated. I am on my way out the door and won't be able to "play" with my mower until the weekend. When I get back into town I will let you know how the readings turn out.

Hi Bill,

I ordered the stator but can't seem to get the nut off to remove the flywheel. Is there a way to lock it down or some "trick" to getting the nut off?

Impact wrench is usually the easiest.

i usually put a 1/2 inch socket on the fly wheel nut ... and then give the ratchet a short hit(s) with a ball peen hammer - to get the nut free.

It doesnt take much to get it loose. (a little WD-40 never hurts either).

avoid using a screw driver between the fly wheel cooling fins to hold it from spinning (keep the spark plug in). You can easily break the fins on some of these fly-wheels... and worse breaking a fin will put the flywheel "out of balance".

good luck

Well - Good news ...bad news.

Good news.I removed the old stator - it was burnt on one side.I changed the stator and it all seemed to go smoothly for a while.
I smelled something burning while I was mowing the lawn. I checked the charging system again and this is what I have (deja vu).

Battery is now charged 12.3DCV. With the engine running at high speed it remains 12.3DCV.

I disconnected the VR from the stator and checed the VAC at the stator leads. It read 22.3 ACV.

As you suggested last time, I checked each stator lead individually against the ground. One was almost 15ACV and the other was about 7ACV.

It looks like the new stator is fried. Any ideas what might be frying the stators?

Since the battery seemed to be charging (12.6V is full), it doesn't seem you have a short anywhere,
That would pretty much leave a bad VR?

My initial thought was IF the battery was entirely discharged, that maybe the alternator couldn't handle putting out the full load.However, I would have expected to burn up within a few minutes, if that was the case, Not after the battery has partially charged and reduced the required load.
Then again, HOW long did it take? The PTO requires about 4 Amps.
Is the VR properly grounded to the engine? I'm not sure if that could cause it or not??

Initially it worked fine. I would say I started to smell something after about 20 minutes.
The VR seems to be properly grounded.

The PTO on the L111 is manual. I wonder if the RIO switch could case a short?

Is it possible that the VR is faulty and causing the alternator to fry?

VR could be bad, but I'd hate to see you replace a good one.

I would do a thorough inspection of the wiring to see if you have a wire with the insulation rubbed bare in a spot. Maybe with the vibration, you've got a rapidly fluctuating short?

I don't know of anyway to test a VR. Maybe someone else?

Does this unit have an ammeter? IF so, what was the reading when mowing?

If it burnt one leg of the stator twice, then I would think that the VR would be very suspect. Especially if it burnt the SAME leg of both stators. I'd be that there is a shorted diode in that regulator. The VR would (should I think) spread the load of the electrical system across both sides evenly, so a problem elsewhre would affect both legs. Maybe I'm wrong, but that is what it sounds like.

Thanks again for the help. Unfortunately no ammeter.

How about checking the resistance through the VR. Will it tell me anything?

"How about checking the resistance through the VR. Will it tell me anything?"

It might???
Since it would probably have diodes, remember to reverse the test leads and check it in the other direction too.
IF you found a direct short to ground from 1 of the inputs, I'd say it's bad. Other readings???
It would seem you should get "equivalent" readings from either input to ground. One may have to have the test leads reversed to do so.
Try various OHM scales, although a short's a short.

It's certainly worth a try!

Shorts anywhere else in the system should be protected by the 20 amp fuse. I think even the charging output is routed through that fuse.

Interesting.

1 input/ground had 6 OHM
the other input/ground had no continuity.

Not entirely sure what that means but I would expect them to be the same as well.

I guess it is time for a new stator and a new VR.

Did you try reversing the leads and seeing if your readings were the same/different?

It's a shame you don't have a known good one to test!

Anybody??

This is my voltage regulator.
{{gwi:335161}}
{{gwi:335162}}

Both yellow wires to ground reads infinity (open) in both directions. I'd say yours is bad.

Looks like the same as mine. So lets assume the VR is also shot.
Can you think of anything else before I change the stator (again) and the VR? I don't want to change everything only to fry it again.

Thanks again.,

Only one thing I can think of, and it is probably overkill. Install a 20 amp fuse in the red wire from the VR. That way if there is a short between the regulator and the battery, the fuse will blow. I think that the regulator just went bad and blew the stator. I don't know why though. Maybe it is just one of those things. Also, you should have battery voltage on the red wire, but maybe only with the key on. If there is not batery voltage on th red wire, then something is wrong.

This is where having a schematic would be so nice.
Typically, you wouldn't have 12V to the Red wire with the key off.
Some tractors even disconnect AND ground that wire at the ignition switch.
My gut feeling is also, that the VR just died and fried the stator.
I would check the VDC off the Red wire after the repair though.

I found a schematic for an L110-120 and the Red wire to the VR is hot all the time.
I don't know if that's the case for the L111, but would think so.

Gents,

Thanks again for your help. The new stator and VR are both in and seem to be working.

At this point in time - everything seems to be working as it should. The real test will come this weekend when I mow the lawn.

Best regards,

AZ

Fingers crossed!

Uncrosss the fingers! Everything worked liked a charm.
Thanks again for your help.

Just to note, when a center tapped stator is used in a charging system with a grounding regulator, a short to the inputs of the regulator will usually result in a burnt stator. The regulator is designed to feed excess alternator output to ground that is not needed to maintain the system at charge voltage. That is not the same as a shorted diode in the regulator, this stops the voltage from being dumped outside the stator and puts all the heat in the winding on the side that is shorted causing it to burn off it's insulation and become shorted to ground as well. Sorry I didn't get in on this post earlier to help.

I am having the same problem with my L111, one of the posts mentioned the parts needed were can I find the stator and regulator on line anyone know?

"I guess the good news is the new stator coil is about $27, while the VR is about $73!
Stator PN 696458
VR PN 691185 "

Google is your friend!
Sometimes, after paying S&H, your local dealer isn't that badly priced.

I looked at the parts break down on John Deere's web site. The stator, they call it an ALTERNATOR and rate it at 10 amps for the L111. John Deere part #AM132174

I called the local dealer and asked about it being 10 amps instead of 16 and he said for the L111 the 10 amp is what is called for and the only one John Deere will sell for the L111.

When My friend removed my Stator it was burned very badly, so I am replacing both the regulator and stator/alternator.

Just thought you might find this of intrest.

Stator is part of the alternator. In this application, the flywheel/magnets are the rotor. You need a stator AND a rotor to be an alternator. They just call it an alternator for simplification, as does Briggs.
Current capacity between the 10, 13 & 16 amp units is determined by the size of the magnets.

Chances are you could save $5-10 by buying a BRIGGS stator for a BRIGGS engine ($25), instead of a JD branded BRIGGS (or lowest bidder) stator.
PN 691064/696458. I'd download the proper IPL from Briggs to verify though.
http://www.briggsandstratton.com/maint_repair/manual_and_more/

Thanks for the clarification and suggestion. I went ahead and ordered from JD, will let you know how it works next week when parts get here.