MG Car Repair/battery


I have a 1969 MGB which has been off the road for six years. At that time I removed the batteries and the connections from the cables as they were corroded. I now do not know whether the car is negative or positive earthed and so don't know how to connect up my two new batteries. Can you help please?
Many thanks

Hi Aidan.  Only the very early MGBs were positive earth.  The changeover was in 1967, so if your car is a 1969 it will be negative earth.  

Your MGB was fitted with two 6-volt batteries which are joined together to make 12 volts.  The earthed battery is on the passenger side of the car.  

Is my answer clear enough, or do you need to know how to join the batteries together?  I could attach a diagram if you need one.  

MG Car Repair

All Answers

Answers by Expert:

Ask Experts


Barrie Jones


MG Sports Cars from 1949 to 1980 - Including MGB, MGBGT V8, TF1500, TF, TD and modern Midgets. I also specialise in SU carburettors, Lucas wiring, suspension, steering & brakes.


I have owned my 1955 TF1500 since 1966. Technical specialist for the TD and TF with the MG Car Club T Register. Also owned 20 MGBs and currently own an MGBGT V8. Written 3 books on MGs and produced a DVD on how to strip and rebuild the TD/TF gearbox.

MG Car Club.

Barrie's Notes on the 1953-55 MG TF (author). /=====/ Barrie's Notes on the MGB (author). /=====/ Barrie's Notes on the MGB GT V8 (author). /=====/ The Essential Buyer's Guide to the MG TD, TF and TF1500. (author)

M Phil, C Eng, BSc (Eng).

©2016 All rights reserved.