12V circuit breaker - polarity sensitive?

[Andy Burns]

[Bob Minchin]

That seems to be more sensible than the original proposal

[Dave Plowman (News)]

Assuming the battery had enough left for the ignition, simply jack up one front wheel, put it in top gear, and spin the wheel by hand. Worked a treat.

[Vir Campestris]

Back in the early 80s I had a Mini. One winter I found that if the overnight temperature was much below zero it wouldn't start. I found I didn't have to push it very hard to be able to bump start it - single handed - and it really mattered to me to make the battery last another 6 months. I needed the money.

Then we had snow.

Andy

[Dave Plowman (News)]

I discovered that with my Mini van too. Until one day it was parked on a steeply camber road, and I couldn't push it away from the kerb between parked cars. Hence the jacking up one wheel trick. The happy days of yoof.