Probably a very stupid question but...

[timig]

Apologies for what may be a very stupid question, but since most people i know tend to drive "normal" cars and not Porsches with 3 litre engines, i was hoping someone on here might help??
My battery has gone flat so i need to get some jump leads, but the shop nearest to me only has leads that officially work on a max of 2.5l engines. Do you think these would carry enough umph to get the 3l s2 engine going? I am too impatient to wait until late next week till they get the more expensive ones that work on 5l cars!
Thanks
tim

 

[mik_ok]

I've never seen leads rated by engine size before.[&:] How do they know (you could blindfold the leads and see if they notice)?

They are obviously limited in terms of current, but I'd try them anyway.

Start the donor car and join your batteries. Rev donor car to approx 2k rpm (so the alternator on the donor car is spinning enough to be charging) for approx 5 mins to give your 944 battery some charge.

Try and start the 944 (with the donor car engine still being held at approx 2k rpm).

 

[timig]

thanks, you are right, they are limited by current, but they suggest that a cable of 220A max current is probably only suitable for 2.5l cars? thanks for the jump starting advice though...

 

[mik_ok]

220 amps isn't a heck of a lot.

Depending on the size of the clamps, you could always use two sets of leads though? (I'd try one set first).

If you need a new battery - worth giving Stu a call for a quote (see Eurocarparts thread at the top of the 944 section).

 

[Alpine]

when my battery went flat I went and bought a charger/conditioner from Halfords for about £35.

It will come in handy if it goes flat again and when i'm not using the car for long periods i leave it on conditioner mode to keep it charged

 

[wizard]

I'm not 100% sure but I think the rating may be for when cranking the engine as this is when most current is drawn. It maybe ok to use them to charge your car without it running for a while, that maybe enough to give the battery enough charge inorder to start. Somebody correct me if i'm wrong.

Edited cause I just said what Mik_Ok said. []

 

[Mark_Bennett]

I once had a cheapy set of charging leads (no idea of rating) and they did not work (I couldn't actually turn a car over with them - let alone start it!).
Tried a different set - and they worked! 2nd set much thicker and better quality.

Moral. Don't bother with the cheap/low rating set.[&:]

 

[Siggy]

When using them, clamp the negitive lead to the engine (of the car you are trying to start) not the battery.

Also when you connect them up remove the keys from both cars, in case the central locking activates as you connect them

Dave

 

[Guest]

As long as the cheap ones aren't too thin, then they will be OK.
They may get a little warm, so you don't want to crank the other car over for more than a few secs at a time.
You might also need to leave 30 secs or so between attempts to stop them getting too hot.

I have done it before and managed to get some smoke off the plastic insulation. If the insulation fails, it would be bad, so keep an eye on it.
The cool quite quickly and generally the clamps are not too hot.

Of course it always best to use the right thing for the job, but it is not always available.
Do not take this as some recommendation, merely note that it is possible with care, if you need to.

 

[Guest]

You will be fine if you just use them to charge the 944s battery, but maybe not to crank the engine. But charging the battery takes forever, so a good compromise is 15 mins charging, then crank with the leads still on. Incidently, the electrical nastiness from the 944s starter may destroy some of the other car's electronics. Modern cars protect their delicate electronics by switching them off when you crank the engine. But they will all be on when you crank the 944's engine....

Probably be OK though []

 

[timig]

thanks all, probably wasnt as dead as it could be - connected it up to a focus with some £15 leads from Halfrauds, left them both running for 10 mins and then took it for a spin - seems okay, but going to test it again tomorrow. Though it was impossible to connect one lead to the battery in the boot of the Porsche and the other one to the engine bay though - gave up and found some other unpainted bit of metal on the car!!