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Alternator Charging
aidan46 - 15/7/12 at 10:17 PM

Hi, I have an 1989 zx10 Kawasaki bike engine. the querie i have is that it doesn't seem to be charging my battery? on my megasquirt gauge the voltage reading its about 11.5 volts.....which seems low....however when i connect or disconnect the connections at the battery coming from alternator you can hear the engine come under slight load as if it was charging?.........any thoughts??????

owelly - 15/7/12 at 11:53 PM

Check the voltage of the battery and then again with the engine running.
You should see about 14volts with the engine running.
Does it start OK? It could be a duff battery.

coyoteboy - 15/7/12 at 11:54 PM

Measure your voltages with, without alt and at higherbrevs. At 11.5 you could have a cell down in the battery.

aidan46 - 16/7/12 at 09:29 AM

Tried it on a few batteries still seems to be the same?

aidan46 - 17/7/12 at 09:56 AM

Any other thoughts on this one?

owelly - 17/7/12 at 11:11 AM

That would depend on your feedback from the suggestions already. What are the voltages across the battery with and without the engine running?

aidan46 - 17/7/12 at 11:18 AM

Only about .3 of a volt in the difference?

coyoteboy - 17/7/12 at 12:42 PM

Sounds like you either have a dodgy connection between the alt and the battery or your regulator is on it's way out. If you leave it running for a few minutes you should see 14v+ with the engine on and maybe 12.6ish with it off. If you've tried other (charged) batteries and still get the same I'd be looking at switching the alt regulator out.

aidan46 - 17/7/12 at 12:56 PM

Right, is that difficult to do? What dose the regulator look like?

daviep - 17/7/12 at 01:48 PM

The ZX10 engine doesn't have an external regulator.

Are you sure that you have the alternator wired correctly?

The black wire which is the output should be direct to the battery
The brown should go to a switched positive with a load (bulb or resistor) wired in parallel.

I can't honestly remember if I wired in a load or not if I'm honest.

aidan46 - 17/7/12 at 02:24 PM

No I havnt got it wired like that..... So the load can just be a bulb like an oil pressure light say for example? Cheers

daviep - 17/7/12 at 02:42 PM

I'm working abroad at the moment so I don't have a manual or my wiring diagram at the moment, I know that I have a charging light on the dash (3w same as oil pressure) but I can't remember how I wired it in.

Cheers
Davie

daviep - 17/7/12 at 02:43 PM

How do you currently have it wired?

aidan46 - 17/7/12 at 02:45 PM

I just have the white and brown from the alt on to the positive and negative of the battery terminal.

daviep - 17/7/12 at 08:40 PM

^^^^That definately ain't going to work.

Try just wiring them both to positive, I'm guessing that the "load" is just to allow the voltage to dissipate when the ignition is switched off

Cheers
(smashed) Davie

aidan46 - 17/7/12 at 09:11 PM

Cheers will give that a go!