HDi Starter Current

[citroenxm]

post deleted.. Silly me not useing my brain what there is of it....

[citroenxm]

Of course.. Stupid bloody question.... Look in the haynes manaul...okay silly me

[Old-Guy]

I suspect you haven't got a reply so far because nobody can quote a definitive figure - BUT you need to assume something over 400A. Maximum current is at the instant that the starter engages with the stationary flywheel and then starts to drop as the engine spins. Thing is, the cable (and any iffy connections) heat up increasing their their electrical resistance so they get hotter... You need to use good quality copper cable at least as heavy as the original and solder the connections unless you have access to an industrial crimping machine.

[Old-Guy]

Of course.. Stupid bloody question.... Look in the haynes manaul...okay silly me

Really? The BoL actually quotes a figure?

[RichardW]

I was going to say the battery is rated at 650A cold cranking current - so 400 - 500A must be in the right region.

BOL? Flabbergasted. Does the Xantia manual even cover the HDi???

[citroenxm]

WOW.. okay, so does this mean the French install UNDER Rated starter motor cables???

My guess is not, the 400a would be total pulled when spun over for more then needs...

Would a length of 135a cable be suitable?? I worked out the one off my mothers HDi 110, on a Y plate was 21mm sq cable.. It had 190 strands at 0.39mm....

So im hoping a length of 20mm sq at 135a should be good enough

[Peter.N.]

You will always get some voltage drop Paul because the cable is underated, you can tell that because it gets warm with continued use, anything as thick or thicker as the original will do, the thicker the better though.

Peter

[DickieG]

BOL? Flabbergasted. Does the Xantia manual even cover the HDi???

Yes

[wheeler]

You will always get some voltage drop Paul because the cable is underated, you can tell that because it gets warm with continued use, anything as thick or thicker as the original will do, the thicker the better though.

The cable on a starter circuit should be OVER rated by about 10% for the maximum current draw of the starter. As a lot of starter circuits are unfused If something were to go wrong for example the engine was siezed then the starter would draw more current than normal, if the cable was under rated this could be a bit of a fire risk. I believe they over rate them to cope with anything like that.
0.5v when the circuit is under load would be an acceptable voltage drop on a starter circuit from the battery post to the starter terminal.

[Peter.N.]

If the engine was siezed the continual current would be at the normal initial current which I'm sure would be well in excess of the cable rating, its unlikely that the cable would fail but all those watts have to go somewhere so if the battery didn't go flat the starter motor would probably catch fire. The cable wouldn't be rated for continual use but by its expected duty cycle, a drop of half a volt would be dissipating 200-300 watts.

Peter