pdm

Hi

Had to jump start the car last week as the battery had died - whats the correct procedure for jump starting ?? The manual suggests putting the -ve lead to the engine mount ???? I didn't have it with me at the time and so put -ve to the -ve battery terminal - will I have done any damage ?

I charged it with a trickle charger this weekend and that said to connect -ve to the battery and leave the caps open a bit ??

How tight should you re-tighten the caps ? Finger tight or with a wrench ?
thanks
pdm

Dill_typeR

The caps don't have to be that tight, they're only plastic threads so will strip easy if you use a wrench. Assuming they have a flat head or philips indent in them, a tweek with a screwdriver will be fine.

Chelspeed

There's a theoretical risk that connecting a fully charged battery to a flat battery will cause flammable gas (hydrogen?) to be vented from the flat battery as it gets a surge of charge into it from the good battery. There's also a good possibility of a small spark as you connect the last of the four connections and complete the circuit.

As sparks and hydrogen don't mix they recommend that the last of the four connections is away from the source of the gas. The last connection should therefore be the negative lead to something away from the battery which is substantial and metal connected to the battery by a decent sized cable, eg the engine mount.

If you didn't have an explosion then you'll be fine, no damage will have been done.