K321 stator

[PetesPonies1 117]

This engine is not charging I have continuity at the two stator leads when unplugged from the regulator. I have no continuity to ground at these leads. I am only seeing 16VAC when running and unplugged, at the stator leads. So . .doesn't seem I have any breaks in the stator, nor do I have short to ground. But . . not seeing the voltage I should see. So . . anyone ever see magnet problems with these engines?

[squonk 38,844]

You may have continuity but high resistance. How many ohms are you getting between leads?

[Handy Don 10,556]

There could also be a short within the windings but not to ground

[PetesPonies1 117]

If the windings we open, no continuity. I'l check resistance.

[Handy Don 10,556]

58 minutes ago, PetesPonies1 said:

If the windings we open, no continuity. I'l check resistance.

Agreed. Thinking of an insulation failure that isn't to ground. It would still have continuity but at lower overall resistance and with one or more coils not generating it would lower the output. I don't know the spec'd stator resistance--should be in the manual.

[PetesPonies1 117]

15 minutes ago, Handy Don said:

Agreed. Thinking of an insulation failure that isn't to ground. It would still have continuity but at lower overall resistance and with one or more coils not generating it would lower the output. I don't know the spec'd stator resistance--should be in the manual.

Right, if it was bypassing the full armature windings. 

 

[Handy Don 10,556]

2 hours ago, PetesPonies1 said:

Right, if it was bypassing the full armature windings. 

 

to answer one of the original questions: can magnets be an issue?

Very unlikely. If a magnet was loose it would most likely hit something with either a mild scrape or a sickening crunch. Ditto if it had fallen out (not unheard of)--they are pretty large and there isn't a lot of room behind the flywheel for one to "hide" somewhere! They are in clusters (six groups of three, I believe) and remember that centrifugal force acts to keep them in place not to dislodge them.

It is remotely possible that one or more magnets have weakened (wildly excessive heat and very strong blows to the flywheel are causes but those would have likely adversely affected other components sooner). The flywheel would have to come off to check them--you could create a simple light rubber-band "scale" to test their attraction to another small magnet or a small metal object (more stretch at same distance=stronger magnet; kinda like a HS lab experiment)!

Were you able to find the spec'd resistance and measure for it? It will be quite low--I think I recall 2 or 3 ohms as the spec for my Onan 218--so you need a good meter accurate to 1/10ths of an ohm?

I've never seen an impedance spec for a stator, probably because it's hard to measure with a simple analog meter. Lots of digital meters have the capability, though. (Impedance differs from resistance because it's measured using an alternating current voltage instead of a direct current voltage and for coils with cores, like a stator, that's a good test.)

Good luck!

[PetesPonies1 117]

I have around 0.9 Ohms through the stator. It bounced from 0.8 to 1.0 , but mostly was at 0.9.  Don, I used to teach Electricity and Electronics in High School. As for my question about the magnets .  I have seen them come loose in other engines and obviously cause an issue with production of electricity. I am not familiar enough with the K series engines to know if this happened as well, that's why my question. 

Edited January 21, 2021 by PetesPonies1

[oldredrider 2,547]

What RPM is the engine turning when you get the 16v reading? 

[PetesPonies1 117]

1 minute ago, oldredrider said:

What RPM is the engine turning when you get the 16v reading? 

You only do checks of this type at WOT.

[Handy Don 10,556]

17 minutes ago, PetesPonies1 said:

Don, I used to teach Electricity and Electronics in High School. As for my question about the magnets .  I have seen them come loose in other engines and obviously cause an issue with production of electricity.

Apologies for the lecture. I too easily don my teacher hat without checking if the info is needed.

The resistance you found seems high. The Onan P218 has a very similar stator and it's spec is for 0.10 to 0.19 Ohms.

This manual from the forum archive has the troubleshooting sequence for your engine but doesn't specify a resistance test. You've pretty much done the tests they have.

 

[PetesPonies1 117]

2 minutes ago, Handy Don said:

Apologies for the lecture. I too easily don my teacher hat without checking if the info is needed.

The resistance you found seems high. The Onan P218 has a very similar stator and it's spec is for 0.10 to 0.19 Ohms.

This manual from the forum archive has the troubleshooting sequence for your engine but doesn't specify a resistance test. You've pretty much done the tests they have.

Yeah, didn't know what I should be seeing. If it's even double what it should be . . then my output makes sense. 

 

[pfrederi 17,128]

When a new after market is  about $30 and a good used one from a reliable vendor is $20 I stop looking at things ...

[Gregor 4,838]

I have 3 K321 Kohlers. If I can get at them tomorrow, I will read ohms across the coils, and to ground.

[PetesPonies1 117]

4 minutes ago, Gregor said:

I have 3 K321 Kohlers. If I can get at them tomorrow, I will read ohms across the coils, and to ground.

That would be cool. Don't expect to see anything to ground if it's a good stator. You will be reading resistance, in Ohms ( there you go Handy Don)  

[Gregor 4,838]

All of my stators read from .2 to .5 across the leads. Nothing to ground. It's pretty cold down there, I may have been shaking a point or 2

 

According to Norman of Isavetractors,  .3 is a good reading.

 

Norman video

Edited January 22, 2021 by Gregor

[PetesPonies1 117]

3 hours ago, Gregor said:

All of my stators read from .2 to .5 across the leads. Nothing to ground. It's pretty cold down there, I may have been shaking a point or 2

 

According to Norman of Isavetractors,  .3 is a good reading.

 

Norman video

Thanks!  So it definitely seems I have double to triple the resistance, even though mine is a low reading. But it is proportional, so my power creating will be inversely proportional and . . thus my output readings are on spot. Thanks

[Handy Don 10,556]

5 minutes ago, PetesPonies1 said:

Thanks!  So it definitely seems I have double to triple the resistance, even though mine is a low reading. But it is proportional, so my power creating will be inversely proportional and . . thus my output readings are on spot. Thanks

Your low voltages make sense now, for sure. So on to find the culprit, or bail and get a new/good used stator!

Connectors at the ends of the stator leads? Nearly severed wire somewhere?

Good luck!

[PetesPonies1 117]

15 minutes ago, Handy Don said:

Your low voltages make sense now, for sure. So on to find the culprit, or bail and get a new/good used stator!

Connectors at the ends of the stator leads? Nearly severed wire somewhere?

Good luck!

Connection plug is perfect . . unfortunately    I'll check all the connections. . but going to have to dig inside I suppose.