Vauxhall Alternator in a series landrover

nitro_warrior · Post by **nitro_warrior** » Sat Oct 02, 2010 5:05 pm

Been a while since i've been on here, but as ever you are my first port of call for automotive issues that are beyond me!!

I have fitted a "new" alternator to my brothers lightweight with a 2.25 diesel engine. Previously it had a alty from a Nissan of some sort. But I wasn't having much luck finding one so have aquired and fitted a Vauxhall one from a 1.7D engine.

So everything is fitted and it looks ok but I can't work out what should plug to what. Previously there was only a positive and an earth.

The new alternator has 3 wires going to a multiconnector, green, black and yellow. And a screw terminal on the back.

With nothing connected I measured the voltage at each terminal and they all read 0V except one which reads about 0.5V.

I suspect it will need a battery connection to start charging but don't want to start plug stuff in in case i break it.

Here are some pictures I would appreciate any thoughts!

Single terminal on the back

excossack · Post by **excossack** » Sat Oct 02, 2010 5:48 pm

Does this link help ?
http://www.vauxhallownersnetwork.co.uk/ ... g-problems.

nitro_warrior · Post by **nitro_warrior** » Sun Oct 03, 2010 5:02 pm

Thanks guys not had a chance to think about it as I was at work today but I was told the seperate terminal my have a marking and sure enough it says BAT next to it.

Presumably that's the positive and of the battery, and I guess it should run it through the ignition relay so it's only live when the key is turned?

nitro_warrior · Post by **nitro_warrior** » Wed Oct 06, 2010 10:13 pm

Ok thanks both for your advice. John, your link seems to confirm Simon's advice.

So I wired it up, the old alternator only had 2 leads connected. The big fat lead from +ve battery to the terminal at the back. And the other lead, that goes from 0v to 12v when the ignition is on, to the black lead in the multi block.

But it still doesn't charge, even when i rev the engine (as i know alternators often need to hit a certain speed to generate).

Would it be that the charge lights not connected? Seems unlikely... I was going to work out where to wire it (there's a spare lead nearby in the engine bay that might be the charge light) but time got the better of me.

ahma · Post by **ahma** » Mon Oct 11, 2010 4:04 am

nitro_warrior wrote:
Would it be that the charge lights not connected? Seems unlikely... I was going to work out where to wire it (there's a spare lead nearby in the engine bay that might be the charge light) but time got the better of me.

Probably, yes. The charge light also supplies "kick-off"or magnitising-current to the alternators field. Once the alty is charging it supplies its own - and the light goes out. You can make a temporary charge light with any 1 - 2 watt bulb. Just put it in serie connection - ignition - bulb - charge light output on alty.

nitro_warrior · Post by **nitro_warrior** » Thu Oct 21, 2010 7:50 pm

ahma wrote:
nitro_warrior wrote:
Would it be that the charge lights not connected? Seems unlikely... I was going to work out where to wire it (there's a spare lead nearby in the engine bay that might be the charge light) but time got the better of me.
Probably, yes. The charge light also supplies "kick-off"or magnitising-current to the alternators field. Once the alty is charging it supplies its own - and the light goes out. You can make a temporary charge light with any 1 - 2 watt bulb. Just put it in serie connection - ignition - bulb - charge light output on alty.

Ok that's a good suggestion, i've not tried connecting that line to the ignition.

Tbh I'm a bit confused with it, and was going to start looking for an alternative, but i'll try your suggstion first.

Turns out the way I had wired it was kind of right. It charges occasionally but then stops and i'm not sure why. It it does start charging as long as you just let it idle it will keep charging but the voltage climbs a little high, I clocked it at 15.5V before I revved it and it stopped charging. If anyone can suggest a simple alternator that works with just an excitation and Bat +ive line and has a vacuum pump let me know!