Thread: D1 dual battery wiring

Will go and take some pics right now. And then I shall post them

Here they are:

Just a note : once a lead acid battery's float voltage (standby V) has dropped below 10 V, you can consider it knackered, it's unlikely it will fully recover.

Originally Posted by Discorock

Just a note : once a lead acid battery's float voltage (standby V) has dropped below 10 V, you can consider it knackered, it's unlikely it will fully recover.

Cheers

Klappers, what battery is your auxilary one? Im looking for one exactly like that one so that it can fit in the tight space without moving the power steering reservoir unit.

What make/brand is it and how much did you pay for it?

Thanks

Originally Posted by steveG

Looks like it was due to faulty batteries.
I knew the second battery was suspect, but after charging overnight it was still no good so I declared it dead.
Supercheap do free battery tests so I drove into there and had the cranking battery tested. It dropped to 9v during the half a second it took to start.

End result is that I've removed the second battery and chucked it, put the original cranking battery in its place, and installed a brand new main one from Battery World.

I know the current second battery isn't great, but it will do what I want for now.

All seems to be happy now, but I still need to test that its OK after draining down to the cutoff voltage.

Steve

I'd be wary of that, I used a cranking battery for my aux, drained it a few times on a Fraser trip when it was a couple of yers old. Shortly after this my nearly new cranking battery died. I had no idea as this was a fairly new battery and it, and the aux were reading at 12.5 volts, though neither would start the vehicle. I tried everything, including replacing starter motors.
Still no good, put in the teensy weensy battery from my Honda Civic and she cranked like a new one.
Replace the aux with a deep cycle, and my starter with a new battery also. All is good till now.
The moral is that one bad battery CAN KILL one good battery.
I'm running a solenoid isolator that cuts at 12V. What good is that when the amps aren't there.

Hi Disco95, if you have a good cranking battery and your auxiliary battery dies. If your isolator cuts out at 12v then you will still protect the cranking battery.

Taking the cranking battery down to 12v will not effect it unless it was on it’s way out and then it would have died soon anyway.

On my D1, I made a small aluminium plate up an bolted the SC40 and the circuit breaker to and just loosened the battery’s hold down bracket, slid one edge of the aluminium plate under the bracket and secured the plate and battery back in place.

This worked fine and fits neatly under the closed bonnet.