MG Car Repair: Battery not holding charge, digital volt meter, fuse box

Question
I have a '79 MGB.  It has a new battery, starts and runs fine as long as it does not sit more than a few days.  If it does sit much more than 3 days, it has no charge whatsoever.  Its as if there is something draining the battery but everything is shut down.
Thoughts?

Answer
Shouldn't be doing that! Must have a drain in some component, I'll suspect the diode in the alternator. However, you can go to the fuse box and preferably with a digital volt meter, check each branch controlled by each fuse to see if there is a drain. You can also just disconnect one fuse at a time and see which circuit you have the problem with...then look at the components on that circuit.  Hope this is of some help, but it will take some work to track down.

Regards,
Brian