Technical Battery warning light flickering dimly

[Uno driver]

You should have a spare, fully charged battery with yourself if you are going to try. Also engine is not running very well without alternator. High idle etc. I did 40km but changed battery once just to be sure it doesnt die in bad situation. I had lights on, but only lights with 5W bulbs. I don't know how you call them, parking lights?

 

[Ucof]

Righto - I think that I won't try and chance it. It's just not worth it in the end.

I think that the alternator that I picked up at the scrappies actually works! I just hooked up the multimeter and span the spindle round and it seemed to register a current. Whether it would output a high enough voltage is another thing when in a car though.

My main battery has just finished charging. It has a voltage of 13.07v. I'll test again to see in the morning how well it is holding a charge.

I also just found out that the square terminal backup battery I have...... has 3 broken cells (there were no bubbles when the battery was being charged up!) so I might as well chuck it out.... or swap it with my dad for a round terminal one

Uno Driver - those are called side lights I think.


...and by the way, LouieBee, you are right about NOT having to take the wheel off to remove the alternator. It is however, much easier if you do!

 

[Louie Bee]

Think with the alternator it will work, or not work, so in less it's a lorry alt for a 24V system the voltage should be OK. let's face it the little Fiat alt looks far too small for a lorry.

Alternators are rated in amps, and for a 999cc car I don't think you can get an alt that is too small if too big I recon it will just charge the battery faster, but not over charge it.

Won't the brushes swap over to the other alt. I looked at putting one of my spare Uno Turbo alternators in but Noooo way will it fit.

 

[Ucof]

The brushes probably would fit over, but its the bit behind the plastic guard that has the melty smell, so I think the whole lot needs swapping over.
Both alternators (the one I got today and my original one) are both rock solid together, I tried pulling them apart but there is no give (yes, I took out the three bolts first!)

 

[alexGS]

It sounds like you got hold of an alternator like the one you linked to on eBay - for the other engine types

I reckon there's a good chance (if they're both Magneti Marelli) that you can swap the rectifier/voltage regulator/brushes across. The plastic cover comes off, then the brush holder, and then to change the rectifier diodes, you have to unsolder three wires. This needs a powerful soldering iron - either 80W electric, or gas.

You don't need to split the alternator casing (the stator former tends to rust and hold the aluminium in place).

-Alex

 

[Ucof]

Thanks Alex, yeah, they are both the Marelli and I picked up the one from the scrappies with the idea of using the parts to repair my original one. Just need to pick up a proper soldering iron now, or will give the scrappies the alternator I picked up in case they need any spares to repair mine.

The voltage on the battery is now 12.85v.

Ah yes, and while I remeber, the brushes on the alternator I picked up were not in very good condition. One was much bigger than the other, so doubt it'd be worth swapping them over.

 

[Louie Bee]

The brushes are diferent lengths as the bottom one pokes out further as the grove it engages into is a smaller diameter

not sure if they started out the same length, but on both my alts one was much shorter than the other. My souldering iron is too small to de solder the long one from the duff brush kit, but that's on the list.

 

[Ucof]

Can anyone give me a hand on this....

I have just tried taking the centre spindle out, by getting a 6mm Alan key head in a socket wrench, and a 22mm spanner and attaching them to the drive wheel (the bit where the alternator belt sits) and trying to undo the nut off the bolt.

Which way are they supposed to go? I assume that the nut turns anticlockwise and the bolt clockwise, right? You see, I tried this way, after they soaked in WD40, but they just wouldn't budge, so I just want to make sure that I am turnign them in the right direction rather than tightening them up.

Thanks all.

 

[Louie Bee]

6mm alan key VS 22mm sounds like it could end in tears

I have had a look in the Auto Data uno manual and it explains stuff for Bosch, Marelli and Mitsubishi alts, with exploded views, but don't say how to remove the centre spindle out. This is AlexGS stuff If anyone knows it would be Alex .

I can't work out you you'd want to remove it in the first place . the brushes are at the other end, between the cover and regulator end support (not fan end)

 

[Uno driver]

It's normal thread IIRC. Put spanner on nut and hit the other end with hand or rubber hammer. Don't try to block fan as you will bend it. There is no need to block rotor, just hit the spanner and nut will undo easily

 

[Louie Bee]

found the lead to the camera..

 

[alexGS]

Uno driver is right on the money. It's never very easy to get that nut off. You only need to take it off if you are replacing the front bearing. Louie is right about the 'ending in tears' part, especially when the Allen key snaps.

The fan will eventually spin on the shaft, so as Uno driver said, don't bother trying to hold that or jam it with a screwdriver.

As for the brushes, I believe they start off the same length - one brush always wears more than the other.

~Alex

 

[Ucof]

I CBA to take it apart now that I know my original one has been reconditioned. £40 + vat it cost Money grabbing B*stards. I could have gotten a new one on eBay for £20 more. Problem hopefully solved now however. Thank you all for the help you have given me, hopefully it will help someone else in the future.

 

[Ucof]

New alternator is in...and I have some good news, and some bad news.

The good news is that it half works...
thankfully, that half appears to be the half that charges the battery up.

The bad news is that the alternator light will not go out.

I am convinced that the battery is charging up however, as after a 45 minute run at around 80mph, the car was still going strong after using full beam, wipers and fan on full speed. After the run, I got the multimeter out and the battery was outputting 13.15V and I could physically hear the cells bubbling away.

So the light not going out makes me think that there is a grounding issue. I disconnected the thin wire from the Alternator, and the battery light didnt come on at all at any stages of ignition.

Anyone got any ideas what is going on and what I should try?

I need the alternator to get to work and back, but the alternator does have a 30 day warranty on it so I can take it back. I'm thinking that it is faulty and that it is causing the light not to go out.

Thanks in advance.


edit - Alternator DOES work - battery voltage with engine off = 12.7V, battery voltage with engine running = 14.6V

 

[Uno driver]

I would take it back. With thin wire disconnected alternator doesn't work AFAIK. Could be broken diode bridge.

 

[alexGS]

I second that - with the wire disconnected, the light should be off, and with the wire connected, the light should come on with the ignition key and go out when the engine starts. Sounds like the small diode - to which the wire connects - may be faulty or shorted. It's good that the alternator is working correctly, though. A sign that you have a pretty minor problem.

Generally-speaking, without the small wire connected, the alternator may not start to charge until much higher revs - or may not charge at all. It's called 'self-excitation' - the ability of the rotating part to produce enough current in the stationary windings to get a useful output - this cannot be relied on. The 'warning light wire' provides a crucial role in the regulation of the magnetic field and therefore the current produced. That is also why the no-charge warning light is a 3W bulb in the cluster - all the others are 1.2W which wouldn't pass enough current for the alternator regulator to work with.

It was fair enough to pay someone to recondition, as long as they have replaced brushes and bearings - at least you now get the convenience of a warranty, even on the bits they didn't replace...

~Alex

 

[Ucof]

The alternator from my dad arrived today, I replaced it with the scrappies one in super quick time (Im an expert at changing them now!), and it all works perfectly. Ignition at position one, battery light is on, when engine is running, light goes off.

Will make sure that it charges the battery before I head off to work tomorrow!

Thanks for all your helps guys (and girls?). I will be taking the scrappies one back to them and getting a replacement.

 

[alexGS]

Great news - so now, you have a spare 'reconditioned' one as well...? Did that get fixed too?

-Alex

 

[Ucof]

I'll be taking it back at the weekend and getting my money back I think. I'm a bit short of cash at the moment, so could do with having a refund.