Broken Alternator

[JuNK512G]

I have a nearly new alternator which has stopped working. The cause, I did some arc welding on the vehicle & stupidly forgot to disconnect the battery, fortunately the battery didn't explode but the alternator ceased to work. I would like to have a bash at repairing it as there seems to be spares available, can anyone say for definite what component has failed ? I don't have test equipment & like everything I try to do is by trial & error usually to my cost.
Thanks, Charlie.

[bmcecosse]

Yes - unfortunately this is a very common failure - the battery is not a problem I have ever heard of - but the alternator (and any music equipment) are at high risk. They MUST be disconnected when any electric welding or 'high rate' charging is used. Can only suggest it will be the diode pack. You will need to know what model of alternator of course - this may suit http://www.ebay.co.uk/itm/ALTERNATOR-RE ... 35b949b7e2 or this
http://www.ebay.co.uk/itm/Lucas-ACR-alt ... 3f1485bd3e

[kennatt]

very likely an acr, and the diode pack is available about £15 and the regulator about £10 the regulator is an easy replacement just screws in the diode pack needs soldering in but easy if you have the solder and gun. Do a search on U TUBE there are loads of demos on how to do it.

[JuNK512G]

Thanks for the help, is there any way to identify the model? I have what I think was the original box labelled Lucas LRA 109 45amp. I had seen the diodes & regulators on Ebay which is why I was trying to establish what part would have definitely gone.
Also on a similar tack, over winter I keep the battery on permanent charge with an automatic 6 amp charger, always disconnecting the alternator & I'm asking if it is really necessary to disconnect it under those circumstances.
Regards, Charlie.

[bmcecosse]

Crikey -6 amp charger is a LOT!! I just use a small solar panel. I see Lucas A 115/127/133 models - I suppose a 109 is just a smaller capacity version of the same type....... Perhaps a kit for a 115 model would be suitable......