Battery draining overnight

[PearlJamKez]

Hi,
I have a 1989 1.6TD, We have recently fitted a new starter Motor which seemed to sort out my starting issue, however, my battery is now constantly draining overnight. My stereo etc is rigged up to the leisure battery so it's not the stereo. We have disconnected the leisure battery in case that was causing it but no luck. I brought a new battery and this too drained overnight. I currently have to either put the charger on it overnight or swap the battery (I have 2 battery's). We have changed some of the cabling from the alternator to the battery as was looking dodgy but nothing has made any difference.

Has anyone please got any ideas what else could be causing this?

Any help much appreciated,

Thanks,

Kerry

[CJH]

I had a similar situation that turned out to be a damaged alternator diode pack - damage that I'd caused by shorting the alternator output to earth accidentally. If you have a multimeter, try putting it in the 'Current' setting (note that the red probe will need to go in the right socket on the meter), disconnect your battery earth strap, and put the meter between the battery negative terminal and the earth strap. That will show you how much current you've got draining your battery. Then disconnect your alternator and see if that current goes away.

Alternatively, if you don't have a multimeter, just try disconnecting your alternator overnight to see if the problem goes away.

[PearlJamKez]

Hi, yes the current went away. What would you suggest I do next please? It went from 2.14 to 0.00 when the alternator was disconnected.

Many thanks,

Kerry

[CJH]

Ok, so it sounds like you need new diodes in the alternator. I took mine to a local starter/alternator refurbishing place, and they fixed mine for, I think, £35. It's more than a regulator swap, and entails dismantling the alternator. Might be a DIY job if that's your thing.

[PearlJamKez]

Thank you! Will see what we can manage ourselves.