flipstah
Leaks.
On something that old you might want to locate, disassemble and clean every electrical ground (earth) connection you can find starting with the battery. Probably ought to clean the hot connection on the starter as well. Toothed lock washers can be a good thing for electrical connections - they provide good "bite" into the substrate at low torque.
Dirty connections = high resistance = bad news (especially in winter).
Nice vintage Rover - I'm envious.
Jim
Replaced the battery terminals and will start cleaning the grounds pretty soon. Need to replace the alternator wiring as well. A lot of work to be done haha!
Thanks!