Battery being killed

[Willemina]

Please bear with me on this! I returned from Spain last summer in my Series 2 FHC and was travelling westbound on the M25 towards the M3. This stretch has a concrete surface with overly large gaps. This meant my car was suffering a 'bang' through the suspension every few yards. After a while my wife noticed that the voltmeter dropped to 12 volts. I made it back home to Ealing OK but am stumped as to the cause. When returning to the car after a few weeks I found the battery completely dead. I replaced it but the new suffered the same fate after just a few days. The car has a replacement alternator but the voltmeter still shows just 12 volts when running. Any ideas as to what is draining it?

[mgcjag]

Sound like possibly a loose connection somewhere that caused your battery not to charge.....start the car and put a volt meter across the battery....you should see something like 14v if battery is being charged......Steve

[Heuer]

Probably the 4TR voltage regulator. Buy a new one and plug it in and see how you get - even if it is not the culprit always worth having a spare for when it eventually (and inevitably!) fails. https://www.sngbarratt.com/uk/#!/Englis ... 295ed269d3

[Willemina]

Thanks. I will change it tomorrow and see what happens.

[AshM]

Any update? It is always useful to get outcomes to problems for reference.

Hope all sorted now.

Cheers
Ash

[Willemina]

Replaced regulator and charging working fine again! This time I fitted a solid state version supplied by SNGBarratt. Hopefully that means the next time I travel on the M25 near the M3 I won't have the same failure. Re battery being killed I discovered a schoolboy error. I had connected the wiring to the 3AW module the wrong way round. As a result I had to fit yet another new battery but this time bought an HB072 from Halfords. Fitted perfectly and is a lot cheaper than the classic version.

[AshM]

Thanks for update and glad it’s all sorted.

Cheers
Ash