For over 50 years I have randomly driven my Austin sevens and enjoyed every moment of the experience however, as a classic car it can often be that I only use the vehicle 3 or 4 times a year and of course this is further exacerbated by the choice of which of the 3 sevens at my disposal.
I learnt many years ago that a 6 volt system can struggle to activate an engine that has laid idle for a period however, what works for me is a s follows………….
I have a small 12 volt car battery that I connect via jumper leads to the Austin. The positive terminal is connected to each battery [my car is negative earth] directly and the negative cable emanating from the 12 volt donor battery connected directly to one of the nuts on the top of the gear box in the cabin.
This procedure allows the engine to turn over more quickly and not damage the 6 volt system and hey presto the motor springs into life.
Importantly, disconnect the 12 volt cable immediately the car has started to ensure that the cables do no overheat.