Engine John Deere 320, possible stator is bad?

[Gumby83]

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.

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).

 

[spepple1989]

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.

 

[Gumby83]

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

 

[spepple1989]

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.

 

[Gumby83]

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

 

[spepple1989]

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

 

[spepple1989]

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?

 

[Gumby83]

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?

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: