QuestionQUESTION: I have a 1972 MGB. I constantly have to buy new batteries approx every 2 to 3 years because the batteries go dead. Last year I left the batteries over the winter at batteries plus with the hopes they wouldn't die. When I picked them up they were gonners. I want to switch over from the 2 six volt batteries to a 12 volt. I here it can be done. How is it done
ANSWER: The easiest way is to fit one 12 volt battery in the right hand bin, but you do need a fairly large battery to replace the power of the two 6 volt ones.
I use an 063 battery which fits the bin, but is slightly too large to go through the hole in the rear parcel shelf. You have to make a small cut in the shelf and fold down the edge so that the battery will pass through. I believe that Bosch now make a slightly smaller battery which will fit without any cutting, so shop around.
Also, the bottom of the battery carrier has an L-shaped lip which would cut into the bottom of the battery, so I fit a square of plywood into the battery carrier to raise the battery by an inch.
The cable between the batteries is now redundant, so take it out and throw it away. The earth strap on the left hand battery must be re-used as the earth for the new 12 volt battery, so you may have to drill one hole in the side of the left hand bin to bolt it into its new position.
You will need a different strap to hold the battery in place, but any 12 volt battery strap will do. You can re-use the hooks from the 6 volt straps.
I use this system on my MGB which has a Buick V8 engine, and it has worked well for the past 6 years. If you want a photo of the battery, I could send one.
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QUESTION: If you get a chance to send a pic that would be great. As far as the battery cables go do I eliminate the cables on the driver side. Should I replace the cables?
AnswerThe middle cable goes through a hole each side of the propshaft tunnel. It runs inside some flexible metal conduit that usually rusts to bits. You will have to cut off one battery connector in order to pull the cable out. It is totally redundant.
No need to replace any cables, just relocate the earth cable from the drivers side to the passengers side. Moss make a plastic battery box. If you fit one to the driver's side, it makes a useful hidden storage space.
Check this reply in a few days. I will take a photo, attach it to a revised answer and send you a reminder to read it again.
