Voltage regulator for 200Tdi alternator?

I managed to flatten the battery on my 1996 110 by using the worklights for too long with the engine off (silly me!). One jump start and a 30min drive later and I thought all would be well. (Ignition light was going off, correctly.) Next day, it wouldn't start!

As I was on holiday I had no multimeter and had to assume that the battery (of unknown age) was suspect. A new battery was fitted, and all seemed OK.

A few weeks (and many starts) later...a 2hour drive to the Great Dorset Steam Fair: it started OK in the morning, but wouldn't restart once we got there. The AA chap tested it over and found no short-circuits to drain battery - also that the fan belt was OK - but discovered that no charge was being produced. Alternator was doing just enough to turn the ignition light off... (Bother!!)

The battery is fine: having bench-charged it, it will start the car happily enough. (How many times can you start a 200TDi in good condition on a new battery if it isn't being charged when you're driving?)

Diagnosis is that a replacement regulator should be sufficient, and that it should be easy enough to fit in situ.

Assuming that I have a standard unit fitted, what is the alternator (is it a Lucas A127??) and does anyone know the part number for the appropriate regulator?

(The AA chap was an ex- vehicle leccy. Said that they used to carry spares of these around, but don't any more. He also said that there were three types available, depending on the alternator: 35, 45 and 65 (amps, presumably), and that the '45' was a sensible choice as it would fit all three, but a '65' in a '35'/'45' wouldn't work as the longer brushes would snap off.)

I'll need to check the unit to confirm its identity before ordering, but was hoping to find some potential suppliers online from work first...

I put a new regulator pack on my alternator but it want something you could do with the alternator on the vehicle, you have to unsolder the old one a solder the new one on. I put some posts on here about it, try a search.

Hi GRUNT

It IS an A127-45, made by Magnetti-Marelli, dated 11-1992 (hence right age, even if not original component). Got a compatible regulator/brush box (made by Bosch) from my local motor factor this morning, but now you's got me worried.

GRUNT said:

I put a new regulator pack on my alternator but it want something you could do with the alternator on the vehicle, you have to unsolder the old one a solder the new one on. I put some posts on here about it, try a search.

Click to expand...

AA bloke seemed to suggest it just slotted in, and the difficult bit was getting the brushes lined up.

I tried (advanced) searching your postings, but I found only one that was even vaguely relevant:
* Regulator
* Solder
* A127
* brush
(nothing)
* Alternator
* pack
1: http://www.landyzone.co.uk/lz/f7/me-battery-warnin-lights-come-58370.html?highlight=alternator -- where you suggest much the same as I've quoted

Could you give us more of a clue please? (Have you changed user names, for example?)

OK, having picked up a replacement regulator/brush assembly i need to try and fit it this weekend, despite the rain...*

In the absence of further responses, I went hunting elsewhere (sorry folks!) and eventually found a thread which answers both our questions... Battery light dimly lit all the time - LR4x4

This thread suggests that the regulator/brush assembly IS a slide-in fit (and hence replaceable in situ) however, there may well be diodes fitted within the alternator casing, and it is these that would need soldering.
The thread also mentions a very helpful illustrated technical article: A127 Alternator regulator replacement

Will find out for certain tomorrow...

*(no covered maintenance area and owning a Defender -- I must be mad!)

Reet then the alternator I was on about is a Lucas and you deffo can't do it in situ. I have had also done a Marrelli alternator and if your patient and have long fingers you probly could do it in situ.

How much did you pay for the Marrelli one, when I tried getting one it was cheaper to get a re-furbed alternator!!!!

Haynes suggests four different alternators: Three Lucas, but the 'Marelli' type is very different, and fitted to later (ie 300Tdi) models.

It is definitely an A127 (but labelled Marelli), with a big silver-and-black regulator box on the back, held on with three bolts. After removing the various air pipes in the way, it WAS possible to remove/replace the regulator box/brushes without touching the alternator mounting bolts.

Unfortunately the (Bosch) part supplied was completely wrong. (I had been assured it was compatible, despite the different shape, but not possible to tell if it would fit unless compared side-by-side. )

The Bosch regulator was very expensive (~£26 inc vat!!) compared to the A127 types I'd seen on fleabay (£7+pp), but I was under pressure to attempt a fix before this evening. I expect to get my money back on it.

Once the old regulator box was back in I decided that the very small (5.5mm) bolt heads would probably not cope with being removed again and decided that a replacement alternator is probably the best bet after all.

Where's a good place to buy a replacement A127 then?

I was quoted that fer the genuine Marrelli bit but when ringing round to find one cheaper I was offered a second hand alternator fer the same price.

Where's a good place to buy a replacement A127 then?

Click to expand...

Try Auto electricians in the yellow pages.

Best I've got so far is £42+VAT from Camberley Auto Factors (my 'local') for their own-brand exchange unit (although after the regulator debacle, I'll want to see one first, just to be certain). Still looking...

if you can be bothered to go that far, go to redhill, (if you know it well enough) behind the ford garage is a little shope called Humphreys & Willis - the bloke who runs it is about 80, but he is really good for auto electrics - have helped me out before, and he offered me a new Lucas alternator for £30, if i swapped him the old one.