stranded in NC - not charging!

Hey all,

My 82 xj750 seca died here in NC as I was on my way back home in PA. She won't charge at any RPM - I'm just getting about 11.2 volts DC At 3000 and 11.3 at 4000. Advanced said my battery has a bad cell so I replaced it with a sealed maintenance free on.e. Replaced battery, which died in same fashion. Im thinking regulator? The Yamaha dealer in town doesn't have one in stock, they say.

I've been caught without my manual and could use any advice you all have

 

http://www.electrosport.com/media/pdf/f ... iagram.pdf

You'll be going to D, and following the advice after determining that the voltage is below 14.5 volts. That troubleshooting guide will get you to your answer.

It is NOT the "regulator" because you aren't reaching regulation voltage. Conceptually, either your alternator isn't outputing A/C enough current (damaged stator, damaged rotor, bad wiring, brush length) or your rectifier isn't rectifying the AC input up to DC voltage. Of course the rectifier/regulator is one assembled unit, just giving you some clarification on that.

From personal experience, I've had the same symptoms twice. Once I accidentally pinched a wire under the alternator cover when replacing it (to check my brushes), and the second time I found that the 3-white-wire connector (the white wires are the a/c current from the alternator and feed into the R/R) had melted shorting two of the wires.

If you ran the new battery down and got stranded again, you'll likely need a new one (they don't like deep discharges)

 

Diagram here http://xjdiagrams.thundervalleypower.com/


Also make sure the red and black wires (DC output) are connected.
I had a bike years ago on which the 12v+ red wire from the alternator corroded in the connector and fell off. What seemed to be an expensive job was actually a few pennies.

 

Unfortunately, depending on the mileage on the bike, you may also have simply worn out the alternator brushes. I'd check those first especially if you don't see any obvious failures in the wiring/connectors.

 

Yea do as the Duck says
Stator went bad or the brushes...also check all your connections
I went through 3 batteries and brushes before I found out it was
my stator...

 

Where in NC are you? If you are in the Raleigh area there are several members here .

 

You guys are fantastic, thank you.

I was running out of time to decide between "troubleshoot and stay the night" or "throw bike in uhaul and drive home."

I selected u-haul, and will revisit this thread when I have more sleep.

thanks again, y'all are awesome.

 

My money is on that outside alternator brush (the one that "travels farther") No big deal to fix, you can find a couple of brushes at any hardware store. I found some in the small engines aisle, I think they were for a lawn mower or gas weed eater or something, "carbon brushes" I think they're called. I had to trim them down a little, then there is some soldering, if I recall correctly. Oh, and polish up the "rings" of the rotor in the alternator, I used an eraser of some kind, don't use any abrasives.

 

Oh, and for this...if you happen to have the manual in digital form, you know, on the computer, maybe a pdf? And any kind of app for documents on your phone (i use "thinkfree office") you can put the manual ON YOUR PHONE. I use capitals because it still blows my mind that I have the whole Haynes manual on my phone. Comes in handy, let me tell you.