OK, it runs. Now a couple other questions....

[DiverRay]

It can short out at ANY PLACE along the way. Both wires have a break in the insulation, the green has a break near metal, or a combination of the two, with oil thrown in for conducting the electricity. A "new" wire should work, but it MAY NOT, so keep that in mind when you first try it. Make sure you can undo the fix easily at first, and make it permanent once you verify it works.

[Larrym]

Wound and Wound!

Rectifier can and does fail in either overcharge or undercharge states. Statistics are misleading here because it's not just which state it fails in but the actions of people. Undercharging is reported more cause eventually the bike doesn't start/run and that's hard to get past. Overcharging doesn't have as many negative symptoms. Bike starts and the lights are just brighter than usual. No need to investigate till it cooks the battery. (Which is usually old.)

Results of the rectifier test were.....ummmm. () Let me look again. Hold on..................

Ok. So you say the green (Dark Green?) wire is "grounded"? I'm picturing you using your multimeter with one end (Black) clipped to ground and the other end (Red) connected to the end of the green wire through the connector at the end of that "sheathed " cable that goes to your alternator. Of course the connector has been pulled out, right? Not connected to anything but air right now? And the reading on the meter is ....showing continuity to ground??

Sadly, my bike is 2 miles away at this very moment otherwise I would take a measurement and confirm the reading you are getting. I wish I could because I don't know what my "working" charging system would read on that green wire.
That dark green wire connects somewhere in the alternator to something else connected to something else ad nauseum. I wish I could verify that the green wire would measure as an "open" with almost infinite resistance in the "static" test your are checking. But Maybe again it is normal??

Semantics, Patrick. Are you sure of the difference between the action of "grounding" the green wire in order to bypass the rectifier and the taking of a measurement of the resistance in that wire and saying that it is "grounded" because you have measured the Ohms between the end of that wire, through a winding, and the point where it attaches to the "ground". Until that winding either moves or has an external field applied to it the static readings may/may not apply.

Take the meter and check out what succubus's green wire tells you.

[TopCatGr58]

Hey Patrick,

The tach not working usually means that one leg of the ALT isn't making a charging current. Did you remove the fusepanel backing plate and inspect and clean up the 3 white connectors behind there that come from the ALT?

As for the green wire, unplug it from the harness at the Reg/Rect location and where it emerges where it plugs into the ALT. Connect your OHM meter positive/red to one end, and the negative of the meter to the frame ground. IF you get any readings, like 0 ohms, or any amount of ohms other than OPEN/no continuity, then it would seem that you have a short to frame. IF it reads OPEN, then the wire is intact, and you can forget about it. I'm not an electrical guru, so you'll need to see the manual and ask others here about further testing of the ALT and reg/rect..
T.C.

Got distracted and when I finally hit send, I see that LarryM has provided a much more thorough response!

[Larrym]

Weasel Clause

Thanks for that clarification, TC!

Good to know what that green wire reading means: Good or Bad.

"Any similarity between myself and a real XS guru is purely coincidental and not intentional."

You may now return to your regularly scheduled troubleshooting process.

[Incubus]

Testing the alternator, these are the numbers I got. I did this once before, but I didn't remember the numbers so I did it again now. I used this posting "Trouble shooting the Alternator" - http://www.xs11.com/forum/showthread.php?t=65 - as a roadmap.

When I test the three white wires with my Craftsman multimeter, I get .7 ohms across all three legs. When I hold the red and black sensors from the MM together I get .3 native resistance, so when I subtract the native resistance my white wires all read .4 ohms, which would appear to be dead on where they should be.

When I unplug the green and brown wires and test the resistance across them, I get 3.9 ohms. Subtract the native resistance of the tool and I get a true reading of 3.6 ohms. The road map says I should be looking at 3.5 ohms, plus or minus 10 percent, so that would also be in the ballpark.

When I reconnect the green and brown wires, and turn on the ignition and test the voltage from each wire to ground, I get 11.6 volts from the brown wire and 1.2 volts from the green wire. The road map says there should be 12 volts between the brown wire and the bike frame and less than 1.8 volts on the green wire.

According to these tests, my alternator should be fine. It also would seem to indicate my problems do not lie between the fuse box connector and the alternator. That leads me back to the reg/rec, or perhaps the wires in the harness between the connector and the reg/rec.

If my testing is not correct or if my reasoning based on that testing is faulty, I would appreciate enlightenment. I also would appreciate any suggestions for tests that do not require me to unwind my wiring harness.

I also have considered that my testing of the running voltage is incorrect. However, touching the red probe to the positive anode and the black probe to the negative anode while the bike is running seems pretty simple.

Patrick

[bikerphil]

I also would appreciate any suggestions for tests that do not require me to unwind my wiring harness.

I'd try swapping the regulator out with a known working one before tearing up the harness. Maybe a nearby member?

[TopCatGr58]

Hey Larry,

From what Geezer has told us, the green wire is controlled by the reg/rect as a variable ground for the field coil, and when the need for more charging power is sensed by the reg/rect, it provides more ground/less resistance to ground the green wire so that the field coil gets more current/stronger and creates more juice! The wiring diagram shows that the green wire should be just one circuit from the ALT connector to the Reg/Rect connector, and so it should be just a single intact circuit/wire between those two connection points. I was just trying to explain about the need to unplug both the reg/rect and the ALT from both ends of that green wire circuit, and then it's a simple continuity test for that wire using the Ohmeter, testing either end of the wire and to the frame. If OPEN, then wire is intact=no shorts to ground. IF any resistance or continuity readings, then it's rubbed raw and contacting the frame somewhere. IF it's found to be OPEN=no shorts, then he can eliminate that wire as a problem factor, and concentrate on T-shooting the ALT and the REG/RECT.

T.C.

[Larrym]

From the well I did not dig..

TC,

You are never going to convince me that you're not smart if you keep up like this.

Yeah. It appears that our bike rectifiers/alternators don't vary much from what is on other similar bikes or on most automobiles. I just didn't know what the resistance reading on that green wire would be in a properly functioning system.

Also the static/resistance/continuity tests for the rectifier are in my Clymers Manual. (Been there and done that.) Every time I have to do that "test" I have to follow the pictures/procedures and even then it's a little clunky. It does tell you if the rectifier is ready for the "Bring Out Your Dead!" or not.

Go to this thread and listen to what Geezer sez about this same test:

http://www.xs11.com/forum/showthread...rectifier+test

His post is a little ways down the page. I agree with him. Describing the rectifier test is hard to do and I certainly hope that Succubus has a manual to guide him through this.

Swapping the "suspect" rectifier with a known "good" one would really cut short the whole process, Bikerphil. I suspect Patrick is about 15 minutes away from doing that right about........NOW!

[Incubus]

OK, today's update. I replaced the rectifier with a known good one I stripped out of a running bike. Poor Succubus. She can't even do the occasional ride with no heart, but there it is. Incubus now charges correctly. I guess rectifiers can go bad and overcharge rather than just undercharge.

The tach still did not work. Poor Succubus again. Stripped the known good tach off of her and installed it on Incubus. That works now too. So it was the rectifier and the tach all along. I've never known a tach to go bad before. I guess there's still a lot of stuff I don't know.

Now I have two bikes and one rectifier. Anybody got a known good spare? I may have to convert Incubus to Special gauges since I have gauges on the '79 Special parts bike. I have a rectifier on there too, but I am betting it is no good. The plastic connectors have crumbled from age, so I'm betting the rectifier is in no better shape. I'll probably try it later this afternoon anyway just to find out.

Now if I could just get the idle low enough to set the timing and synch the carbs....

One good update. The moisture has been cooked out of the crud on the outside of the engine, so it doesn't smoke anymore. And it sounds really good when I rev it.

Patrick

[Larrym]

Locked In

Congrats on giving your inner ears a well deserved break! It's fun to spin around in circles as a kid but the novelty wears off after a certain age.

The rectifiers are just a bit of electronic components tied together. Sadly, you can't just go in there and replace a transistor because the whole unit is "Potted" in an epoxy. That may work in your favor here because no matter what your "Unknown" rectifier looks like on the outside, it may make the little electrons go about their merry way just like they're s'posed to.

The known "dead" rectifier, (Moment of silence, please....), still may be of help. The plastic connector on it may be exchanged for the sketchy one on the yet to be tested unit. I use a small flat jeweler's screwdriver to depress the small tab which locks those little male/female spade/bullet connectors inside the plastic housing. If you remove one connector then you'll see how and where to release the rest using this method.

There's no substitute for being able to clean and recrimp these little connectors while they're outside the plastic housing. Like opening pandora's box it generally leads to one doing all the connectors on the bike.

Eye-balling that dead rectifier with a new interest?

At least you don't have dig it up from a graveyard under the cover of night.

[TopCatGr58]

Hey Patrick,

Geezer sells a better than OEM replacement Reg/Rect for the XS, see the Parts for Sale Forum, Sticky thread! Lifetime guarantee....Geezers' not the bike! Otherwise, it's a crap shoot on ebay! But perhaps someone has a parts bike with one?
T.C.