Flat battery - managed to bump start - what next?

James2k

Don't listen to the drama queens, its not good for the battery but the chances are if its not too old that it will be perfectly fine.

As said, if after an hour driving it doesn't start again next time, then its time for a new battery anyway. especially with the cold weather coming.

fred990

Richard53 wrote: »

By 'a couple of maintenance cycles' I assumed he meant a couple of sessions with the charger, not the time after charging. I have an Optimate and have used that to resurrect several batteries. An intelligent charger is a good investment

Indeed. I've found so far the CTEK one is better than my Optimate version. The Opti can't quite get near the 15V+ (ish) that the CTEK does, I've yet to check what the current is during this oscillating recovery/desulphation phase (very low obviously).
As you say a good investment.

Richard53

fred990 wrote: »

Indeed. I've found so far the CTEK one is better than my Optimate version. The Opti can't quite get near the 15V+ (ish) that the CTEK does, I've yet to check what the current is during this oscillating recovery/desulphation phase (very low obviously).
As you say a good investment.

I bought the Optimate for motorcycle batteries, so perhaps it just has a lower work rate than the CTEK. It does the job even on a 110Ah battery, it just takes longer. I had a mower battery which was totally and utterly dead, not even a spark. I put it on the Optimate thinking I would see if I could bring it back to life. I had to leave it on charge for over a week before the charge light went green, but it recovered the battery to the point where I got two more seasons out of it.

sevenhills

bluedrop wrote: »

Hi all,
I forgot to switch off the headlights while going into the gym today. The battery went flat by the time I came back about 1.5 hrs later. Luckily, the car was parked on a sloping road so I managed to start it. Drove around for about an hour after that (picked up my husband from his office 30mins away).

Have I damaged the battery?

If there was zero charge in the battery, a rolling start would not have worked, so your battery was probably just not charged enough to start your car.
If you are on a budget, it may be ok. I had the same happen to me about a month ago.
Its been ok since, but I keep listening exspectingit to do it again. A new battery for my Megane 1.6 will be around £50 I really should buy one.

If you can afford a new car, I would say shop around for a new battery.

Richard53

sevenhills wrote: »

If you are on a budget, it may be ok.

In April, I would say the same. In November, I would say get a new one.


Cold weather reduces the battery's output, and at the same time makes all the oils in the engine thicker so it is harder to turn. A double whammy if a battery is already weak.