MGB Register Forum

Just before our very successful MGB Register weekend in Cornwall the batteries failed on the GT. Discussion with John Watson produced the recommendation that I replace 2 x 6 volt with 1 x 12 volt - this is an excellent suggestion as 6 volt batteries are not easy to find these days.

However John suggested I buy a type 063 12 volt battery so I went to the local Halfords and bought a lovely VARTA type 063. It looked a bit large but I took it anyway, trusting John's advice.

I can tell you now, a type 063 will not fit the battery box on a 1974 BGT - it was an inch too wide so I took it back to Halfords along with the old 6 volt battery as a sample. The base dimensions are critical because the battery box will not accept anything bigger than 6" square. John did say that the trick was to cut the lower lugs off the sides of the 063 but that would (a) still leave it slightly too big and (b) invalidate the warranty.

At Halfords we went along the battery shelves until we found a 12 volt unit with the same base dimensions as the 6 volt one. That battery is a Halfords
BATTERY-B HB202. It is slightly lower in height than the 6 volt battery but still tall enough for the battery holding down clamp to be used and it drops straight into the battery box without any modifications at all.

Because the terminals are positioned differently on the top (6 cells instead of 3) you may need another earth strap - and I discovered there is already a hole drilled in the bodywork to accept a 1/4" bolt in exactly the right place if, as I did, you install behind the driver's seat rather than behind the passenger's.

Does it work? YES it performs brilliantly but I am still getting over the backache of reaching in through the driver's door to make the change!

I put a baler twine string around my 12 volt battery, like tying up a parcel, so it can be lifted out.
other left hand battery box is empty. Any alternate uses for it as it is a bit open to the under car weather down there?

Here are some pictures of my battery installation, the empty compartments carries a selection of spares in a waterproof box, these are available from Moss Europe

This is the battery type most used in MGBs pre rubber bumper when converting from 2 x 6 volt.

http://www.tayna.co.uk/Type-202002L-Var ... P9038.html

I fitted one three years ago - no problems maintenance free and cheap enough to throw away if it fails after the 4 year warranty period.

It is B36 standard and at £52 delivered home the next day good value.

See all the good reviews from MGB owners.

As Roger discovered a type 63 battery will not fit easily a pre rubber bumper car which was designed for a type 63.
I know I have tried using the battery from my RV8.

With modern battery developments there is no need for physically big battery nor 2 x 12 volts in series.

Add electronic ignition and the old MGB is a fast first time start too.

George

Re Davids comment about a use for the empty space having now only got one battery - i think you can buy a storage 'bucket' that can be used to keep tools etc in. Very handy.

I take the point about using the spare battery compartment for storage but there are a couple of downsides for me. Because I strained my back considerably just exchanging the battery on the driver's side, I just disconnected the battery on the passenger side and left it there. It has taken me about 6 weeks to recover !!

Even if I remove the old battery some day I doubt if I will want to use the space for storage as the same back trouble will occur again trying to access whatever I might store there. I have lived with UAE57N for over 30 years and have found all the storage I need around the spare wheel where everything is sufficiently well packed not to rattle and yet quite easy to get at when required.

I was very interested to learn that the 063 battery will fit the later cars but not the chrome bumpered ones - a useful point to know.

Roger C.

Also just picking up on your point about the baler twine David, - an excellent idea but not necessary with my new 12 volt battery as it has a built-in handle.

HOWEVER>>>>>>>>> I do use a piece of baler twine tied to the gearbox dipstick/filler making it much easier to pull out through the very sharp edged hole in the transmission tunnel. Had that in place for years!

I had the same experiance as Roger, the recommended battery was too large and I also chose a suitible battery from Halfords. I happened to have an MX5 12 volt battery from an old golf cart so I fitted that in parallel to the 12 volt battery above, and since then the car has started amazingly well. The MX5 Battery was a much better fit than the conventional one from Halfords and much easier to fit and remove.

I have been running 1X12v batteries in my '63 B' for many years now. According to my notes I replaced a Halfords HB 004 in 2008 with a Japanese J50R from a local supplier (the R denoting terminal handing so no problems with earths, clamp etc.). I have had no problems with them fitting in the bay but made my own clamp from galvanised steel covered with shrink sleeve to safely secure the battery.

I´m using two 12V 36AH in parallel since 19 years and it works perfectly. They are cheap and last for 6 to 7 years. You only have to measure the battery compartment.