Verify my judgement please?

so. my 81 750 seca quit the other day as i was just getting to work. i determined quickly that it wasn't charging. after some reading, it appears that the green wire out of my rectifier should have an output of 14.5V and the brown wire should have a variable output of 9-11V depending on RPM of the motor.

i put a voltmeter on the connection after charging the battery and starting the bike, the brown wire is outputting the 9-11V, but the green wire is outputting 0.96V, not varying by RPM. it seems to me that the regulator is gone, but i wanted to verify before i go out and order a $90 part.

i assume that if the alternator brushes were buggered i wouldn't get the 9-11 out of the brown wire. i checked the white stator wires, they all show 0.4 to 0.6 ohms resistance. i can't seem to find the alternator connector, and my Haynes manual isn't much help finding it.

so, my questions: does that sound like symptoms of a bad regulator?
where is the alternator connector?

thanks for the help.

 

You may simply need a ~$15 alternator BRUSH kit and a quick cleaning while you are in there.

Alterntor is on left leg side. The Aluminum cap with 3 screws and some wires coming out of it from a rubber grommet on the cap (DON'T loose the grommet). You should also buy a new gasket if you need new brushes.

FYI: Brushes are actually little metal bars that wear own. The original ones have small wear lines on them to visually check if they need replacement.

I don't remember the min length is. I think it was 11mm...

I know I took some pictures, but I can't find them on photobucket.

 

by way of update, i checked the brushes on my lunch hour. both are over 20 mm long. resistance on the stator is good(ish). i'm more sure that it's the voltage regulator, or maybe a crappy fuse, since it's the original fuse block.

 

Before spending the big bucks on the new regulator. Spend the $10 - $15 it will cost to replace that old unreliable fuse block. It is known to be a major cause of many electrical problems.

Once done with the fuse block. Double check all the electrical connections in the wiring harness. Yes, that includes the speghetti bowl mess in the headlight bucket. Making sure that all connections are clean, and tight.

If you still have a low reading on the green wire after doing the quick, and easy stuff. Then proceed onto the regulator.

Ghost

 

you can buy a blade style fuse box real cheap locally. then just go to the local pick and pull junkyard and grab the fuses you need. cheaper than having to buy 5 of each, lol. usually they just give them to ya for free. or just toss em in the toolbox

 

fuse block is definitely on the agenda, but would that cause a low reading at the regulator pigtail?

 

I know I had a charging issue when I accidentally pinched 1 of the 3 white wire under the alternator cover. After fixing it, the plug later melted, shorting two of the contacts. Check all of the wiring and connectors in the charging circuit. The regulators are pretty tough, and don't fail often, connectors, wires, and fuse boxes are another story.

 

ended up being the regulator. apparently there's a moto salvage near where i am, and i picked one up for $21.