Charging voltage

[sandwave]

I've not had confidence in the charging system on my 02 leMans for a while (flickering battery light, left me with no power once then I changed the battery).

 

I've been using a battery tender to make sure it stays up, but thought I'd look into it further today.

 

To my surprise, the voltage across the battery terminals at ~3,000 rpm got over 17V. My first thought was a dead regulator, but then I found another thread in here that mentioned 18V charging voltage and no-one commented.

 

Is 17+ V normal? I expected 14-ish. Before I started the bike the battery was at 12.7V with the ignition off, so it is OK (and my meter is probably not smoking crack either).

 

Thanks,

 

Dominic

[luhbo]

...Is 17+ V normal? I expected 14-ish. Before I started the bike the battery was at 12.7V with the ignition off, so it is OK (and my meter is probably not smoking crack either)....

 

 

This will destroy your battery. 14.6 is maximum. Have you a good ground connection for the regulator?

 

Hubert

[dlaing]

My first thought was a dead regulator, but then I found another thread in here that mentioned 18V charging voltage and no-one commented.

What!?! Let me at'em!!!

I need to comment!

As Luhbo says, 14.6V is maximum (at least according to the manual)

Could be bad wiring, bad fuse, bad ground or bad regulator.

Also, the regulator gets it baseline from a line that passes through the notorious starter relay on early V11s, and goes through the lighting relay on all V11s, so the relays may be suspect, too.

I'd start with swapping relays around assuming yours are all 5 pin. Keep track of which went where. If that does not fix it look to the fuse, clean it, move on to wiring, and ground and clean them, testing for voltage output as you go.

But don't stay at 17V for long as the battery and other things like the ECU could get cooked.

[sandwave]

What!?! Let me at'em!!!

I need to comment!

As Luhbo says, 14.6V is maximum (at least according to the manual)

Could be bad wiring, bad fuse, bad ground or bad regulator.

Also, the regulator gets it baseline from a line that passes through the notorious starter relay on early V11s, and goes through the lighting relay on all V11s, so the relays may be suspect, too.

I'd start with swapping relays around assuming yours are all 5 pin. Keep track of which went where. If that does not fix it look to the fuse, clean it, move on to wiring, and ground and clean them, testing for voltage output as you go.

But don't stay at 17V for long as the battery and other things like the ECU could get cooked.

 

 

Thanks! Yup, didn't look right to me. I'll go through the steps you suggest, and no, I won't be running it in the meantime ... guess I'll have to take my 82 CBX instead... darn... :-)

 

Dominic