How long can the battery be disconnected.

[grasmere59]

When i get a moment i'm going to take the duff alternator off but i'm in no real hurry as i'm probably not using the car for a couple of weeks this will also leave myself some time to source a replacement,once the battery is disconnected how long can i leave the car like that? I was thinking of just disconnecting the 12v lead to the alternator and insulating it so it can't short out and leaving the battery connected?

[Doggy]

It doesn't matter how long, the important thing is to follow the correct procedure for connecting and disconnecting it, (in the KB).

Never followed it myself. Not sure if it means you have to have your driver's door window open for the duration.

If you're sure you won't get it wrong, I would just disconnect the alternator, (but then I blow stuff like this up all day for a living).

The safe option is to disconnect the battery first.

[grasmere59]

Surely i have'nt got to have the drivers window open for the duration,if the bonnet was open and the doors shut but unlocked with the key out the battery could be disconnected after 10 mins or so without any dramas?,if the doors etc are opened after the battery has been disconnected that can't do any harm can it? or does the bsi have somesort of backup battery.

[lozz]

Have someone sat in the driver's seat for when you reconect the battery.

that shouid phase out having to ave the window down id think,

Imight be wrong tho as usual,

[Doggy]

Can't see why lozz's suggestion wouldn't work, guess it was written with garages in mind where leaving the window open is less of an issue.

[lozz]

That Method works on chitron piccasso's.
drivers window never works on them, so thats how people get round it with them,

so id guess it shouid work on a 406. as per theyve the same/simalar - BSI B/s

[grasmere59]

I could always pay a small child to sit in there for the duration

[lozz]

Its a shame they dont have a door switch like Most cars,

shame you carnt get at them to wedge them so theres no circuit, so when you open the door it wont wake the BSi up,

[grasmere59]

I never gave it a thought or even looked but how does it bring the interior lights on when you open the doors?

[jasper5]

As Doggy said, the safest thing to do is to disconnect the battery, but my preferred option is to always leave the battery connected and to insulate and tie up the alternator wires in a safe place where no contact with earth can be made.

I often tape up my sockets in case I touch earth when undoing the alternator leads.

I do this on all modern cars to avoid computer issues.

It's your car, so your call.

[grasmere59]

I think i'm going to insulate the 12v lead as i've been bitten by the "immobiliser fault" on my old Rapier when i messed up the battery disconnect/reconnect lark and it cost me to have it reset.I think i'll cut a couple of fingers off of a pair of kitchen rubber gloves and double them up over the cable end.

[DaiRees]

I often tape up my sockets in case I touch earth when undoing the alternator leads.

I once earthed an alternator I was removing, through the spanner to the bulkhead via a small gold ring I used to wear on my little finger. Damn that hurt!!

[Welly]

I don't understand the fuss? why can't you just disconnect the battery (disconnect earth lead first, reconnect last) tape up the leads and that's it? why fiddle with the window?

[steve_earwig]

It's this stuff about disconnecting/reconnecting the battery in the KB, part of the procedure rather involves leaving the driver's window open, which is obviously a bit silly if the battery's being left off for a long time...

[jasper5]

I often tape up my sockets in case I touch earth when undoing the alternator leads.

I once earthed an alternator I was removing, through the spanner to the bulkhead via a small gold ring I used to wear on my little finger. Damn that hurt!!

Ouch!!

Mechanics are not allowed to wear jewellery for this reason.

I can't wear my wedding ring at all these days due to arthritis, my knuckles are badly swollen.