Charging Help! (evil red light)

[dkilmer]

ok, a new stator, new brushes, new rotor, new voltage regulator, tested good bosch diode board (plus attempting new thunderchild), new battery and still the RED LIGHT GLOWS. put a voltage tester on the battery no volts above 12.60, cleaned and dialectric greased all connections. according to the charging manual by motorrad everything is good.

but why! damn you red charging light!

any input PLEASE!!!

(1975 R90/6)

[N7RKS]

Light is always on my bike, until it hits 1200 rpm then it goes off (this is normal), yours always on? Might have a short on the light wire, rubbing and touching the frame...

[dkilmer]

red light always on, plus no charge after any rpm, it stays at 12.6 volts

[20774]

What was the situation with charging before you changed all the parts? Since it appears you've changed everything, there's something wrong with the wiring. My guess is that you have a wire that is grounded that shouldn't be. IIRC there's a specific order of washers that must be used when putting the brush holders back into place...something along that line. If you get the isolating washers in the wrong order, you'll have a path to ground where it shouldn't be.

Double check all wiring and make sure everything is right...

[Rod Sheridan]

Hi, remove the battery negative lead, then remove the front engine cover

- re-connect the negative battery lead

- start the bike, measure the voltage at the alternator brushes, be careful not to get the leads tangled in any rotating parts.

- if there isn't any voltage at the brushes, the alternator won't produce any output

- stop the engine, remove the positive field lead from the alternator brush

- connect a voltmeter to the battery, start the bike.

- momentarily connect a jumper from battery positive to the alternator field positive brush. If the battery voltage rises, your alternator is working. Be careful to not exceed 14.5 volts at your battery.

- if the alternator works, check the wiring and voltage regulator.

- if the alternator doesn't work check rotor, stator and diode board, as well as diode board grounds.

Regards, Rod.

[Boxerkuh]

Do you have the Electrical bible from Motorrad Electric? Also, this month Airhead magazine has a nice article about just that....