sounds like the inner stator coil isnt being charged, does your dash light come on then go off when running, or stay on dim?
 
sounds like the inner stator coil isnt being charged, does your dash light come on then go off when running, or stay on dim?

It's my 2nd/Aux alternator and the light I've got wired up in the cabin comes on and stays on, no dimming at all.

I can't understand this (Grrrr). All I did was tighten up the red HD cable and heard a crack. Now I've got my 2nd/Aux alternator out of action and the main battery following suit.
 
the light means its not generating power, could be down to multiple reasons .
not turning fast enough, bad earth, bad regulator, bad diodes.
can you get to the brushes? if so test both against the earth with the ignition on, and engine off. 1 should read 0 (earthed) and 1 should read 12v
 
You've probably twisted the terminal on the alternator and snapped the connection. I did it many moons ago in a previous life as a spotty teenager.
 
You've probably twisted the terminal on the alternator and snapped the connection. I did it many moons ago in a previous life as a spotty teenager.

Sounds like the right kind of noise I heard. Is is repairable? I've been on Yell.com and spotted,
Vehicle Services, 22 Kingston Road, Freemantle, Southampton, Hampshire, SO15 3DB

who do "Starter &Alternator Repairs". I see you are in Southampton, do you know them at all?
 
If the light is on and stays on in my experience, this is down to the alternator earthing out.
Put simply, when the ignition is on, power flows from the battery to the dash bulb and back to the alternator. With the engine not turning or at least not turning fast enough, the alternator becomes an earth for the bulb, (this is what it is supposed to do). When it spins fast enough it stops going to earth and becoms a live supply. Therefore the light goes out. But........ if you make the other side of the bulb go to earth it will light again. So when you check it, check the wires to make sure they are not damaged or earthing anywhere. :)
 
Sounds like the right kind of noise I heard. Is is repairable? I've been on Yell.com and spotted,
Vehicle Services, 22 Kingston Road, Freemantle, Southampton, Hampshire, SO15 3DB

who do "Starter &Alternator Repairs". I see you are in Southampton, do you know them at all?

Nope never heard of them but then I tend to fix my own bits and normally just shop for bits on line. As for it being repairable that really depends on the model of alternator.
 
Just been out and whipped the cover off.

The crack that I heard was in the plastic cover, you can see it in the photo at 8 o'clock on the top hole. This has happened because there is no support underneath it - should there be?

IMG_5683_zps1a97d8be.jpg


You can see from this side view - nothing under the nut which is in roughly the same position when the cover is on. To me, it looks like something is missing.

IMG_5681_zps76b73eb1.jpg


IMG_5682_zps929cc629.jpg


All looks well underneath.

IMG_5685_zps9a554a08.jpg


Still perplexed as to why the removal and replacement of a lead can cause alternator failure and then a subsequent battery failure on an unconnected battery. I'll see what state the battery is in first thing in the morning.
 
re the batt failure of the first bat from the second alt.

did you wire the 2nd alts warning light to the second battery or did you use a point from your dash?

if it was from the dash, then you are feeding the exciter from the first bat, and if the alt has earthed then it has drained your bat down? though you would have had the warning light on, and presumably used an ign switched wire.

luckily you have two alts, so you can swap wires over to check to see if the alt works properly with the other setup and diagnose that way.
 
did you wire the 2nd alts warning light to the second battery or did you use a point from your dash?

It's fed from the 2nd battery through an ignition switched relay. I did my homework on that one. :D Worked flawlessly until I took the lead off to shorten it.
 
It's fed from the 2nd battery through an ignition switched relay. I did my homework on that one. :D Worked flawlessly until I took the lead off to shorten it.

haha, good work.

so if you took the wires from the 1st alt and stuck them on the second alt, then you should be able to see if the 2nd alt is feckered as it now becomes your first, and you know that works fine (i presume).

or more simply, switch your alt wiring around to see if ones bust.
 
haha, good work.

so if you took the wires from the 1st alt and stuck them on the second alt, then you should be able to see if the 2nd alt is feckered as it now becomes your first, and you know that works fine (i presume).

or more simply, switch your alt wiring around to see if ones bust.

Easier said than done. With the TGV engine, the main alternator is buried and virtually inaccessible to somebody with fat hands. :eek:

I've disconnected all of the 2nd alternator leads so that I can rule that one out! I've also dropped an email to Gwyn Lewis with photos. I've never dealt with him before but by all accounts he's very good so fingers crossed.
 

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