Poor Charging

My 1982 XJ1100J charges @ 14 volts @ idle and goes down to 13.4-13.6 volts at all rpm above that.

Volt meter wiggles at idle gets steady above idle.

New brushes (100 miles on them) no difference.

(Old brushes weren't down to the wear indicators and they had 30,000 miles on them that I put on and they were used when I got the bike!)

Checked the rectifier with the service manual and it checks out ( assuming I checked it correctly).

%%^@@&^&^%$ wires from the stator melted together a few years back and I repaired them .

The resistance across the field circuit was .8 ohms IIRC vs. .4 ohm per the manual but I am not sure I checked it right.

Damaged stator?

Fragged wiring to the brushes?

Any recommendations as to the order to check things?

Thanks in Advance,

TECHLINETOM

 

from information overload I suggest you read it
http://www.xjbikes.com/forums/threads/the-information-overload-hour.27544/



Charging System Tests:

a) Adjust voltmeter to DC volts (20 volt range).

b) Place voltmeter leads to the battery terminals (positive to positive and negative to negative).

c) Start the engine.

d) Bring engine up to approximately 2,500 rpm's.

e) Compare the voltage reading to the specification given below:

For all XJ-series models, the maximum available charging output VOLTAGE should be as follows (all values are approximate):

* approximately 500-2000 rpms: 1.8 volts gradually increasing to 14.2 volts
* 2000+ rpms: 14.2 volts up to about 14.8 volts, with a maximum of 14.8 volts (all models except XJ700-X and XJ750-X)
* 3000+ rpms: 14.2 volts up to about 14.8 volts, with a maximum of 14.8 volts (all XJ700-X and XJ750-X)


NOTE: the voltage reading must be approximately 14.0 - 14.5 volts to properly charge an AGM battery......anything less, and you will quickly kill these type batteries!

If your charging voltages are too low, suspect the alternator brushes first, then perform the alternator stator and rotor checks as described in the Alternator Section elsewhere in the catalog.

If your charging voltages are too high, suspect your Regulator - Rectifier unit first, and perhaps dirty or corroded electrical terminals. The procedure for checking these is too detailed to describe here, and you should consult your service manual for additional details.