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Discussion Starter #1
Well....I was driving home one day, saw my headlight flicker (was somewhat dusk) was like...wtf? Looked down at my volt meter and it was pulling 12's instead of 14's...

I made it home barelly with it in the 11v range after that I tossed a battery tender on it for the next couple days, 12v+ fired right up.



First thing I did when I got the bike was relocate the rectifier. So, I sat out, tested the 3 yellow wires OFF the rectifier harness, all 3 went up, same voltage, with the revs. I figured because of this, stator was fine.


I figured the rectifier took a crap. Well, my new one came in today, plopped it in, 12v+ off the tender charger, fired up with a little help in this cold weather. Took it around the block...no change. Would NOT get above 12v. I didn't ride it long enough to see if it would drop or stay at 12v.

I measured right at the battery 12v on the nuts...


So, rectifier good/new, stator seems to be good after those yellow wires I tested (I redid all the stator connections and soldered them this summer), battery is a sealed maint free, brand new, obviously holding a charge.

So..tell me the bad news..what's goin on? :(
 

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Check that the R/R is getting 12V to the brown wire. If it does, measure the charging voltage right at the regulator output - the white wire. Finally, check the voltage at the black/yellow wire of the R/R - should be close to 0V.
 

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Discussion Starter #3
I'll check em when I get home tonight, or later tonight hopefully and get back to you all. The rectifier is brand spankin factory new, so it deff isn't the problem, but I will check those.
 

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Discussion Starter #4
Yup, all 3 were dead on.


Black (ground) was 0v, middle (monitor) was 12v, and the far end (battery) was 12v too.

I just don't get why I can't get the bike to charge. All the stator wires go up and down with the throttle.


Maybe they aren't pushing enough power???? Stator??? Is there ANYTHING else this could be??
 

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The Junction Box (Fuse Box) could be wonky. There is a relay in there, or connection. The power goes from stator to R/R, from R/R to JB, then it goes to the battery. So if you can trace the wire leaving the R/R and check voltage at the R/R.
 

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Discussion Starter #6
That might make sense, because it was like a 'switch' just clicked and all of a suddden BAM my lights just dimmed and I just knew something wasn't right until I looked at the volt meter.

I'll check that tomorrow. I realize these relays either work or don't, most based on magnets to work. Any real way to check them? pull em and check for the "click" they make?
 

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Black (ground) was 0v, middle (monitor) was 12v, and the far end (battery) was 12v too.
Sorry for not being specific, but I wanted you to test the regulator output (at the regulator) with the engine running. 12V is what you would expect with engine stopped, but it should rise to somewhere around 14V when you rev the engine. If not, then the regulator is shot. If the voltage does rise at the regulator output but not at the battery, then you can look for the problem between the regulator and the battery.

You did not tell if the stator voltages between the phases were good.
 

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Discussion Starter #8
The sator voltages rise and fall with rps, if they're in the correct values, i'm unsure. I have to get in in there to replace the leaking oil gasket anways so i'm probably going to just replace the damn stator while I'm at it.

Like I said, the rectifier I got (thinking it was the original problem) is a 100% brand new factory rectifier. It can't be the problem. Not when two rectfieries (old and new) are reading the exact same outputs at all wires... No chance in that, the problem MUST rely somwhere else....

Sadly at this point, I think the stator is working enough to provide "readings" on my voltmeter, but not enough to charge the bike.


I remember my rectifier used to get hot to the touch, it's cold as ice now, even with the brand new one : /
 

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the stator voltages should be from the 50 to 70 volt AC range when read phase to phase on all combinations of the three phases if it is much lower than that or if any phase of the stator shows continuity between it and ground on the engine case the stator is probably bad,remember to check the stator voltage on the ac scale and regulator,output on dc
 

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Discussion Starter #11
yeah, I need to check them on a/c my dumbass left it on dc and just saw numbers jumping and assumed it was charging.


I did the continuity test to ground, the stator is NOT grounded out....
 

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Discussion Starter #12
Sorry for not being specific, but I wanted you to test the regulator output (at the regulator) with the engine running. 12V is what you would expect with engine stopped, but it should rise to somewhere around 14V when you rev the engine. If not, then the regulator is shot. If the voltage does rise at the regulator output but not at the battery, then you can look for the problem between the regulator and the battery.

You did not tell if the stator voltages between the phases were good.

Sorry, my mistake, the voltages were with the engine RUNNING, so yes, I was surprised to see the rectifier not pushing at least 13+ at high idle (had to choke it was so cold), so rectifier was putting out 12v+ to the battery while it was running at high idle.


I just can't wrap my head around the rectifier being bad....no returns on electrical parts and it was factory wrapped new.... doing the exact same thing the old one was. It's go to be something else.
 

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Discussion Starter #13
Sadly, I don't think it's the junction box. I just don't see how it could/would be. I've checked all the fuses in it. And, it makes no sense that the rectifier wouldn't be outputting enough voltage.

My guess is, sadly, the stator is pushing less than adequate voltage to provide more than what's needed at the rectifier to have it push more than 12v+. : /



So, if the stator's the case, I was going to do the side gaskets for oil anyways since they had a slight leak in them requiring me to remove the piece anyways. Might as well replace the stator while I'm in there this winter.


People recommend going factory stator? Aftermarket? Website? What's the most reliable option for one?
 

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People recommend going factory stator? Aftermarket? Website? What's the most reliable option for one?
tim perrrot enterprises

i highly recomend these guys to rebuild your stator.. . though it takes a couple weeks to get it back to u the quality and output is unbeatable
 

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Discussion Starter #15
Thanks for the link.


I've seen horror pictures of others with plastic melted off, do they all come like this? just some?? it was blue plastic, it melted all over the magnets on someone's stator.... I forget the site.
 

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Sparky!!!
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I just can't wrap my head around the rectifier being bad....no returns on electrical parts and it was factory wrapped new.... doing the exact same thing the old one was. It's go to be something else.
you replaced the rectifier but that didn't fix your charging problem, you say you get how many VAC? what is the voltage with the bike warmed up to opperating temps at idle, 1500 rpm, 2500rpm, and 4500-5000 rpm?
If your voltage stays at around 12 volts through the whole rpm range, and you are getting good VAC at the stator wires... then you have a bad ground or a bad JB... I replaceed my stator three times, and the R/R twice b4 i replaced my JB (for a whole different reason). after replaceing the JB, the charging system all of a sudden worked.

Now you say your fuses are good, so how could the JB be bad??? well here is how.. the JB is not just a fuse box. it is also a housing for internal relays and diodes that can go bad... the brown wire that goes to the R/R is tied into the white battery wire with a diode inside the jb... check the voltage going into the JB on the white wire, and voltage out on the brown wire. I am 99% sure it is your JB after reading your symptoms and every thing you have done thus far... I hate to see you spend more money than you need to on a stator just to keep having the same problem.
 

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Sparky!!!
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I just can't wrap my head around the rectifier being bad....no returns on electrical parts and it was factory wrapped new.... doing the exact same thing the old one was. It's go to be something else.
you replaced the rectifier but that didn't fix your charging problem, you say you get how many VAC? what is the voltage with the bike warmed up to opperating temps at idle, 1500 rpm, 2500rpm, and 4500-5000 rpm?
If your voltage stays at around 12 volts through the whole rpm range, and you are getting good VAC at the stator wires... then you have a bad ground or a bad JB... I replaceed my stator three times, and the R/R twice b4 i replaced my JB (for a whole different reason). after replaceing the JB, the charging system all of a sudden worked.

Now you say your fuses are good, so how could the JB be bad??? well here is how.. the JB is not just a fuse box. it is also a housing for internal relays and diodes that can go bad... the brown wire that goes to the R/R is tied into the white battery wire with a diode inside the jb... check the voltage going into the JB on the white wire, and voltage out on the brown wire. I am 99% sure it is your JB after reading your symptoms and every thing you have done thus far... I hate to see you spend more money than you need to on a stator just to keep having the same problem.
 

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Discussion Starter #18
haha me too man, me too. Is the junction box on the BACK of the battery? or the fuse box itself.


I've tested the white wire at the rectifier, easy enough, the junction box wire seems more difficult to get to. How exactly should I test that?
 

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Sparky!!!
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the JB is part of the Fuse Box... i don't have my manual right next to me, so I can't tell you which pins to test. just trace the wire from the R/R back to the JB.... and i bet that the white wire would be giving you battery voltage while the brown wire gives you zilch
 

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Here is the wiring diagram:

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No diodes involved except what is in the R/R. One way to test is this:
Disconnect battery negative terminal. With ignition on, measure continuity from the brown wire at the R/R to the battery positive terminal, white wire at the R/R to the battery positive terminal and black/yellow wire at the R/R to bike frame. All should show close to 0 ohm.

The junction box is only involved in the charging system by the current to/from the battery going through the main fuse in the junction box.
 
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