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1Back to top Go down   What should the charge voltage be? Empty What should the charge voltage be? Mon Mar 05, 2012 6:13 am

Cleverbee

Cleverbee
active member
active member
Having found a repaired abs brain from Tosi, he has asked me to check the charge voltage between the positive terminal and chassis st 1500 to 2000 rpm.
Having done so, the voltage shown was between 51 & 54v dc!
Surely this cannot be correct.
Before I blow anything up does anyone have an answer?

    

RicK G

RicK G
admin
admin
The voltage should be between 13.8 and 14.2 volts. At 50 odd volts its a wonder you have any electronics left. Remove the alternator and get it repaired it is the only thing that can produce voltages like that and do not start the bike again untill it is fixed.


__________________________________________________
"Man sacrifices his health in order to make money.
Then he sacrifices money to recuperate his health.
And then he is so anxious about the future that he does not enjoy the present; the result being that he does not live in the present or the future; he lives as if he is never going to die, and then dies having never really lived."   Dalai Lama


Bikes 1998 K1100 LT, 1993 K75 RT, 1996 K75RT, 1986 K75 GS, 1979 Z1300 Kawasaki
    

charlie99

charlie99
VIP
VIP
crikey mr bee ....that sounds weird ......are you sure that the output of the altenator is tied to the positive of the battery durring this measurement ?

without starting the bike ...at the same point that you measured before ...what is the reading ?

tis quite common for altenators without a load (or in this case a "good" positive for feedback - load ) ..they will climb above the normal voltages we expect ...

could of the feed from the altenator to the battery lost contact somehow ....corrosion etc ????

    

Cleverbee

Cleverbee
active member
active member
This was measured with circuit tester on positive terminal of battery and engine block.
The bike is running fine, all electrics apart from abs.
Is there a better way to measure the output?

    

charlie99

charlie99
VIP
VIP
im amazed !... check with volts again between the battery negative and the engine block


__________________________________________________
cheezy grin whilst riding, kinda bloke ....oh the joy !!!! ...... ( brick aviator )

'86 K100 RT..#0090401 ..."Gerty" ( Gertrude Von Clickandshift ) --------O%OWhat should the charge voltage be? Au-log10

'86 k100 rs.. #######..  "Fred " (f(rame) red ) ( Fredrick leichtundschnell ) - -
bits and pieces from many kind friends across the k100 world ...with many thanks ..
    

robmack

robmack
Life time member
Life time member
The Bosch alternator is a three phase alternator. The DC setting measures the RMS value of the voltage so an AC component may give you the reading you are measuring. May be a blown rectifier in one of the phases of the alternator. Put the meter on a low AC setting and test. If you get any AC value above say 0.7 Volts, then the alternator is suspect IMO.


__________________________________________________
Robert
1987 K75 @k75retro.blogspot.ca
http://k75retro.blogspot.ca/
    

japuentes

japuentes
Life time member
Life time member
Hi there, just and idea, but if the bike is running fine I would also check the volt meter.
Best regards
JAP

    

charlie99

charlie99
VIP
VIP
could be right jap ...would love to see the setting of the meter and the meter

got a pic cleverbee ?


__________________________________________________
cheezy grin whilst riding, kinda bloke ....oh the joy !!!! ...... ( brick aviator )

'86 K100 RT..#0090401 ..."Gerty" ( Gertrude Von Clickandshift ) --------O%OWhat should the charge voltage be? Au-log10

'86 k100 rs.. #######..  "Fred " (f(rame) red ) ( Fredrick leichtundschnell ) - -
bits and pieces from many kind friends across the k100 world ...with many thanks ..
    

Cleverbee

Cleverbee
active member
active member
PHEW !!!

Panic over, re-checked the output, but this time across the terminals of the battery.....
14.08v DC @ 2000rpm.
However, positive terminal and engine casing measure 16.8v DC @ 2000rpm.
Is this correct?

    

10Back to top Go down   What should the charge voltage be? Empty Re: What should the charge voltage be? Tue Mar 06, 2012 4:07 pm

charlie99

charlie99
VIP
VIP
measure the same .....battery negative and casing ..you could have a losy negative cable ,,,( the connection at the frame could be corroded or as we have found ...the cable needs to be upgraded to something thicker )


__________________________________________________
cheezy grin whilst riding, kinda bloke ....oh the joy !!!! ...... ( brick aviator )

'86 K100 RT..#0090401 ..."Gerty" ( Gertrude Von Clickandshift ) --------O%OWhat should the charge voltage be? Au-log10

'86 k100 rs.. #######..  "Fred " (f(rame) red ) ( Fredrick leichtundschnell ) - -
bits and pieces from many kind friends across the k100 world ...with many thanks ..
    

11Back to top Go down   What should the charge voltage be? Empty Re: What should the charge voltage be? Fri Mar 09, 2012 8:01 am

Cleverbee

Cleverbee
active member
active member
Well, I've upgraded the negative cable with 7mm, plus used the same gauge to bond the block, bellhousing and gearbox together.
Removed and checked alternator, those little monkey balls were a bugger when putting back on, kept falling out, but a little bit of contact adhesive to lightly hold them in place did the trick.
Thanks for all your help. 2 months to go to France, Switzerland, Germany, Luxembourg and Belgium.......!

    

12Back to top Go down   What should the charge voltage be? Empty Re: What should the charge voltage be? Fri Mar 09, 2012 8:28 am

RicK G

RicK G
admin
admin
Thanks for all your help. 2 months to go to France, Switzerland, Germany, Luxembourg and Belgium.......!
Now I am jelous have a good time and take heaps of pictures for us

Yeah they can be a real problem. I used superglue and I have heard that some use silicone. So we can add another trick to the list thanks to a very cleverbee.


__________________________________________________
"Man sacrifices his health in order to make money.
Then he sacrifices money to recuperate his health.
And then he is so anxious about the future that he does not enjoy the present; the result being that he does not live in the present or the future; he lives as if he is never going to die, and then dies having never really lived."   Dalai Lama


Bikes 1998 K1100 LT, 1993 K75 RT, 1996 K75RT, 1986 K75 GS, 1979 Z1300 Kawasaki
    

13Back to top Go down   What should the charge voltage be? Empty Re: What should the charge voltage be? Fri Mar 09, 2012 3:42 pm

K-BIKE

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Life time member
Life time member
I know this is not the case here but as a caution never disconnect the battery on a bike or car when it is running since once the revs rise over tick-over the alternator voltage output will soar up to as much as 100+ volts at full revs and all electronics will be fried in a heartbeat it is a very expensive lesson to learn. The same can happen due to the main battery cable becoming disconnected by a failed cable connector whilst driving.
Regards,
K-BIKE

    

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