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Discussion Starter #1
Hey guys, I need some help. I have read everything in this forum about stators and regulators and I still can't explain what is happening. So here is the run down of what has happened so far:

battery not charging - 12.3-12.5V when running idle-4k rpms
Replaced stator and still not charging, about the same readings. Checked stator voltage - about20vac at idle and 45vac at 4krpm. Regulator output about 12.5 at 4k rpm. Tested voltage drop of wires while running, white on regulator to positive on batt - 0.2v, same for ground. Then the headlight quit. I moved the blue wire and we have lights again. Replaced R/R and got same readings. Now one leg of stator is reading 100mV and about 40ohms to ground when running, which tells me it's bad. Brand new regulator and brand new stator. No power shorts to ground. I don't think my origional R/R was bad, but what is making my stator blow? I have only rode it about 5 miles. I can replace the stator again, but I need to find out why it is frying.
 

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The Professor
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Hey guys, I need some help. I have read everything in this forum about stators and regulators and I still can't explain what is happening. So here is the run down of what has happened so far:

battery not charging - 12.3-12.5V when running idle-4k rpms
Replaced stator and still not charging, about the same readings. Checked stator voltage - about20vac at idle and 45vac at 4krpm. Regulator output about 12.5 at 4k rpm. Tested voltage drop of wires while running, white on regulator to positive on batt - 0.2v, same for ground. Then the headlight quit. I moved the blue wire and we have lights again. Replaced R/R and got same readings. Now one leg of stator is reading 100mV and about 40ohms to ground when running, which tells me it's bad. Brand new regulator and brand new stator. No power shorts to ground. I don't think my origional R/R was bad, but what is making my stator blow? I have only rode it about 5 miles. I can replace the stator again, but I need to find out why it is frying.

Never test the stator to ground when running, test the stator to ground with engine off and set MM to ohms. Your charging problem could be the JB, the white wire w/red tracer comes from the R/R and goes to the JB and then to the battery. This is the wire that charges the battery. Your stator voltages are fine, check and clean your frame ground connections. Check the white/red wire comming from the R/R and see what the voltage is.
 

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Discussion Starter #3
I checked the white wire with one lead on the regulator and the other on the battery and there was onlt a .2 voltage drop when running, telling me that there is no resistance between the regulator and the battery. The same measurement was done on the blk/Ylw to ground. I just checked the stator again, by unplugging the regulator and measuring between two legs of the stator and all measurements go up to 50vac at 4krpm, so I guess the stator may be working. I still only get up to maybe 12.5vdc directly out of the regulator. The brown wire, however, is about .5V under the white wire reading, both compared to the blk/ylw. Also the blk/ylw has also been spliced directly to ground close to the battery. I don't get it.
 

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Old Truck Junkie
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I have a brand new r/r and I am getting high 12.? on the road. When I turn the auxilary lights on the charging volts go up to 13.3 or so. I am not having any problem with that voltage yet.
 

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The Professor
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I checked the white wire with one lead on the regulator and the other on the battery and there was onlt a .2 voltage drop when running, telling me that there is no resistance between the regulator and the battery. The same measurement was done on the blk/Ylw to ground. I just checked the stator again, by unplugging the regulator and measuring between two legs of the stator and all measurements go up to 50vac at 4krpm, so I guess the stator may be working. I still only get up to maybe 12.5vdc directly out of the regulator. The brown wire, however, is about .5V under the white wire reading, both compared to the blk/ylw. Also the blk/ylw has also been spliced directly to ground close to the battery. I don't get it.
Did you replace the R/R with a new or used one?
 

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does the blk/ylw where it is spliced directly to the frame also attach to your large black battery negative cable,if not it should as it is the battery negative lead back to your r/r and the brown wire is the load wire for you various devices ;ie headlights signals and all other electrical components control circuits and actually could drop voltage over those circuits from the resistance of the loads.It appears that your wiring is in pretty good shape but it seems that your regulator is dropping off at a lower voltage than it really should ,you may have a bad new regulator ,it is not unheard of and will drive you nuts,was your old r/r fried or did you just replace this one when you replaced the stator to be on the safe side.turn the lights on and signals and tie the front brake in with a zip tie and load this r/r up and see if your voltage goes up under demand or drops, if it drops you have a bad r/r if it comes up to around 13.2 or maybe more, it may be doing all it will do,especially if you have a good strong battery in there . Load it up at around three grand to give it a chance to work,and go from there,JMO
 

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Discussion Starter #7
Yes, it is a new regulator. I replaced it when I replaced right after the stator because the voltage just would not come up. The blk/ylw wire is tied in where the neg. batt. cable ties to the frame for good continuity. The voltage does increase as the rpm increases, so it is a promising sign. The batt. voltage is about 12.1 and it stays there at idle, it goes up to about 12.5-12.6when revving. The R/R is on a bracket by the back tire for fresh air and has been since I bought the bike. All of the lights are on all of the time, I had to bypass the headlight relay because it quit, while I was working on the charging system, does that mean anything? I will try to run an extra light or something off the battery tonight for a little more draw to see if it does anything.
 

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Yes, it is a new regulator. I replaced it when I replaced right after the stator because the voltage just would not come up. The blk/ylw wire is tied in where the neg. batt. cable ties to the frame for good continuity. The voltage does increase as the rpm increases, so it is a promising sign. The batt. voltage is about 12.1 and it stays there at idle, it goes up to about 12.5-12.6when revving. The R/R is on a bracket by the back tire for fresh air and has been since I bought the bike. All of the lights are on all of the time, I had to bypass the headlight relay because it quit, while I was working on the charging system, does that mean anything? I will try to run an extra light or something off the battery tonight for a little more draw to see if it does anything.
It means that your headlight relay ,which is internal to the junction box, is not working for whatever reason shorted /open,but there are a few people on here who are running their bikes with the headlight relay jumped over without any ill effects,I suspect your charging system is working but the regulator side of the r/r is just dumping voltage to ground at a lower voltage than most,the bottom line is does the bike run right and start back after riding normally or does the battery not stay charged enough to operate the bike correctly?Sometimes good enough is good enough although if it worries you , it wouldn't hurt to try a different r/r if you have access to a known good unit.
 

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Discussion Starter #9
I have not taken it out for more than a couple of miles for fear of it burning something up. I have also kept it on a battery tender. I do have a fairly new R/R and a new R/R that show the same readings when running. I guess measurements are one thing, but since everything seems ok, i will just ride it and see if it charges and forget about the MM readings for now. I guess I'll just stay fairly close to home.
 

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Hmm.. Could it be that your MM is showing incorrect readings? Especially if it is analog and old, you can expect it to show too low readings.

I had to bypass the headlight relay because it quit, while I was working on the charging system, does that mean anything?
Perhaps. The engine is running and the stator is connected to the bullet connectors but not to the regulator. The regulator does not limit the stator output voltage and the headlight relay gets that too high voltage. Fries either the diode or the relay coil. When measuring the stator no load output voltage, measure from the (disconnected) bullet connectors.
 

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Discussion Starter #11
I have a good Fluke meter, so no problems there. But I have tested it a couple of times from the unplugged Regulator plug rather than the Stator plug itself, so that could explain the headlight issue. I guess I won't do that anymore. Also I replaced the bullet connectors with a 3 position Delphi weather pack connector for better connection and reliability. As for the different readings, I am leaning more towards gremlins at this point, I guess I need a bell. It runs great and has not died on me yet, so I am going to ride it for a couple of days and check the voltage before I hook it to the battery tender. maybe it works, but with a full battery it shoots it all to ground. Not like the car systems I am used to, but who knows.
 

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Discussion Starter #12
Well it would not start today, so the system is definitely not working. Any Ideas? New regulator, new stator, R/R good continuity to ground, good continuity to batt + and brown wire (ref) is about .5V under battery voltage when running. I am only getting approx. battery voltage 12.2-12.6 from idle to 4krpm. It does rise with rpm. I am measuring about 48vac between any two legs of of the stator. Any ideas, I am stumped.
 

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How about something killing batt when the key is off???
he's right you know ,try leaving the battery cables off over night,hook em back up and see if it will start .Make sure the battery is fully charged when you do this and you can eliminate battery problems as well as find out if you have a key off battery drain,and you very well may have if the headlight relay is shorted to ground as opposed as to being an open circuit.
 

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Discussion Starter #15
It started this morning and again after leaving the first place I went, but the 3rd place, after about 30 minutes of riding is where it wouldn't start. I will check for drain on the battery tonight. First I will disconnect it, hook up my meter in line and see if it draws any amps with ign. off. I guess I'll just have to start bringing my jumper pack with me, i hate being stranded.
 
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