Valeo Alternator Insides

Clogzz · Post by **Clogzz** » 29 Nov 2010, 14:35

That’s not too bad yet, mine made it to over 100,000 km with more crackles and didn’t break.
From what I’ve read, if it’s crackled all over every inch, then it’s due for renewal.
I used to watch the edges for fraying more than crackling of the ribbing.

HDI · Post by **HDI** » 29 Nov 2010, 15:57

Although I don't doubt that sort of mileage is possible from a ribbed belt I wouldn't advise leaving it to the point of risk. If it were to break it could become entangled in the cam belt with obvious consequences

addo · Post by **addo** » 02 Dec 2010, 21:31

Touch vinyl, it's still unbroken.

Getting back to the core issue of electrics:

If the starter was shorting - would the current drain not cease upon release of the key?

Because this is the "weird" part - once it's done the naughtiness, it stays flat (for want of any better word). I can take the key out and there's barely enough current to light the interior lights, and not enough to lock the doors.

I've been hatching another theory.

As I usually have the aircon running, when the car starts it instinctively (via Bitron controller) tries to put the fans on low speed. I know my fans are not well, as the relay contacts have been melting again recently. What if there were a serious short through a stalled cooling fan, or a dodgy relay or Bitron? Enough that while it didn't blow the fuse, it took away the solenoid's ability to pull in, and the dash/CPH functionality.

I'm almost keen for it to happen again, so I can test this theory! (Of course, if it's wrong then I'm still up the creek without a paddle...)

Part II of my questions now, relate to alternator isolation.

If I ran a dedicated cable with 150A capability direct from the alternator output to the battery terminal and lopped off the original at the starter (or vice-versa) am I compromising any aspect of current flow? To a layman's mind I can't see how, but not an expert...

HDI · Post by **HDI** » 02 Dec 2010, 22:11

Did you do any voltage checks yet ?

Post by **Peter.N.** » 02 Dec 2010, 22:20

Last things first, as long as the alternator is connected to the battery, where it goes on the way is irrelevent, although the shorter the path the better.

If the battery goes flat or appears to when you try to start it, there are three possibilities, 1. the battery is flat, 2. the battery is faulty, 3. you have a faulty connection on the battery or from the battery to everything else which goes high resistance when you apply a load to it.

When the battery appears flat connect a voltmeter across it, make sure you connect it to the actual battery posts not the lugs, if it still shows 12 volts or more, turn on the ignition or lights or anything really to put a load on it and check the voltage, if it has now dropped well below 12v its either flat or faulty, if its still reading around 12v you have a bad connection somewhere.

Peter

addo · Post by **addo** » 02 Dec 2010, 23:38

Yes, when either restive (with the subject condition extant) or with the key turned to "D" it still registered 12.7V - as a side note the store battery tester showed 12.8 so my kit isn't too inaccurate!

I've kicked a few cars around and this is one of the more difficult problems I've chased.

From memory (can't find the screenshot to verify) end of last year I was showing a charge voltage in the mid-low thirteens, whereas now it's over 14. Haven't changed any electrical components inbetweentimes.

Snagging a Valeo reg/brush holder and possibly diode packs seems like a good possible "hedge" against it being a generation/rectifier problem. Does anyone know what is in the rebuild kit PSA sell - just the reg?

Post by **Peter.N.** » 03 Dec 2010, 00:11

That would seem to confirm that your battery is OK then so you need to check further down the line, sounds as though you have a fault on the main supply somewhere. First check the voltage on the battery terminal connectors as a poor connection between them and the battery is quite common. Check between earth and batt + see if you have 12v+ when under load, if so the fault must be in the + supply. Check for 12v on your cigar lighter, if its not there run a lead from batt+ to the live connection and see if it 'wakes everything up'.

Battery voltage with engine running should be just over 14v so that sounds OK.

Peter

addo · Post by **addo** » 12 Dec 2010, 09:37

Just noting no recurrences to date; I have adopted a routine of turning the A/C switch off whenever parking up, and not putting it back on until the car is started.

Given the recent weather I often start the car by reaching in, then reach across to put on the A/C - then stand outside for a minute or two while it gets up to height and cools the cabin somewhat.

Over the next week, I'll drop this (A/C off to start) habit again, and see if the problem returns.

addo · Post by **addo** » 14 Feb 2011, 08:27

End diagnosis an odd one: poor crimping into the positive terminal.

Terminal became hot under "no start" conditions, whereas wires and battery post didn't. An almighty squeeze or two with the mouldygrips on the terminal crimp area seems to have ameliorated the condition.

Really, though, crimping five wires into one hole on the connector is a bit daft of PSA.

Post by **Peter.N.** » 14 Feb 2011, 09:59

There you are then, it was easy really

Xantidote · Post by **Xantidote** » 14 Feb 2011, 12:27

well done, problem traced. Maybe you'll need to remake or resolder the wires properly?

At least you didn't have the cables catch fire/burn out on top of the battery

HDI · Post by **HDI** » 14 Feb 2011, 14:33

I suggested battery cables in the 4th post on this thread

Post by **CitroJim** » 14 Feb 2011, 17:17

HDI wrote:I suggested battery cables in the 4th post on this thread

It's getting quite a frequent problem now...

HDI · Post by **HDI** » 14 Feb 2011, 22:04

Indeed, Xantia's are getting on a bit now ! Battery cables and terminations get a hard life, battery end terminations are exposed to the damp and salty breeze from under the bonnet edge, combined with high starting current and hot and cold cycles corrosion is inevitable.

I use purpose made battery terminal grease on all my vehicles now and it seems to reduce problems in that area. It also changes colour to yellow if acid is present for any reason, which is a clear early alert to impending problems.
Preventative maintenance is the key.

addo · Post by **addo** » 14 Feb 2011, 22:24

Not many damp salty breezes here, unless locust plagues are corrosive.

Going to investigate my options for an aftermarket style distribution block, with only a short single cable from the battery to a small bus bar. A new Citroën cable is 65 Euro plus postage.