Alternator failure

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Dru
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Alternator failure

Postby Dru » Tue Jul 09, 2013 9:27 am

...or at least, presumed alternator failure!

During some dramatic stop-start manoevring on a hill the other day, an unusual whine developed, coinciding with the blue light coming on. I got home, and took the alternator out.

There was a fair bit of carbon powder in there, and the brush that goes in the outer run (the one on the right in the photo) is quite worn but still in contact with the rotor.

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examining the brushes on an alternator by Dru Marland, on Flickr

...I cleaned everything up and replaced them, and bench tested it - span alternator by hand, with meter across the output terminals. Utterly zero voltage. Is this an ex alternator, do you reckon?

bmcecosse
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Re: Alternator failure

Postby bmcecosse » Tue Jul 09, 2013 9:33 am

Well - BLUE light is main beam warning - not alternator......which would normally be the RED light. Your brushes look ok - swap them over - the outer track brush always wears more. Spinning by hand will do nothing - stick it back on the car and see what happens. If you have a meter - you are looking for 13.8 volts when you rev up.
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MarkyB
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Re: Alternator failure

Postby MarkyB » Tue Jul 09, 2013 9:46 am

Connect it up to the cars loom before you test it or you will kill it.

"Once you break something you will see how it was put together"

Dru
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Re: Alternator failure

Postby Dru » Tue Jul 09, 2013 9:50 am

whoops- sorry! RED light stays on, not blue!

Dru
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Re: Alternator failure

Postby Dru » Tue Jul 09, 2013 11:30 am

sorry, Mark- I missed your reply there. Oh dear....

Well; I changed the brushes over, reassembled, and put the alternator back on.

Voltage at battery (engine off) 12.6v
Voltage at battery on fast tickover 12.1v

Voltage across terminals of alternator 9.5v

Ignition red light remains on and bright during running

...and the alternator is whining again. There is a bit of play on the rotor; I guess a bearing is about to throw its hand in, too :roll:

rayofleamington
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Re: Alternator failure

Postby rayofleamington » Tue Jul 09, 2013 12:18 pm

If it was me I'd consider converting to a dynamo - but I doubt anyone else will suggest that! (sorry) :roll:
Ray. MMOC#47368. Forum moderator.

Jan 06: The Minor SII Africa adventure: http://www.minor-detour.com
Oct 06: back from Dresden with my Trabant 601 Kombi
Jan 07: back from a month thru North Africa (via Timbuktu) in a S3 Landy
June 07 - back from Zwickau Trabi Treffen
Aug 07 & Aug 08 - back from the Lands End to Orkney in 71 pickup
Sept 2010 - finally gave up breaking down in a SII Landy...
where to break down next?
2013... managed to seize my 1275 just by driving it round the block :(

Dru
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Re: Alternator failure

Postby Dru » Tue Jul 09, 2013 12:35 pm

:D

well, call me stravagant if you like, but don't call me late for lunch. I've just ordered a new alternator from ESM.....

bmcecosse
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Re: Alternator failure

Postby bmcecosse » Tue Jul 09, 2013 4:51 pm

It does seem to be poorly - but these alternators can be repaired you know....... ESM - hmmm - won't be inexpensive..... No scrap yards in your area ???? I agree with Ray - a dynamo is very reliable and plenty of electrical power for a standard car - UNLESS doing a lot of commuting in winter when it will struggle with heater+wipers+headlamps etc in stop-go traffic......for that you DO need an alternator.
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smithskids
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Re: Alternator failure

Postby smithskids » Tue Jul 09, 2013 10:58 pm

Yes, you can't beat a simple dynamo, the old ones are built like a brick toilet and can be skimmed many times, the voltage does drop after many skims as the commutator gets smaller.Of course you can always give it a boost trickle charge at night. My MM minor and morris 8 are still on there original dynamos. Keep em running. :D

irmscher
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Re: Alternator failure

Postby irmscher » Tue Jul 09, 2013 11:12 pm

what about a solar charger with the dynamo pretty cheap now

Trickydicky
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Re: Alternator failure

Postby Trickydicky » Wed Jul 10, 2013 7:58 am

irmscher wrote:what about a solar charger with the dynamo pretty cheap now


This is how I keep the battery topped up at the moment, works well for me with a dynamo and a standard set up. I don't have any gadgets.

Solar chargers are still cheap!!!

http://www.maplin.co.uk/solar-powered-1 ... rger-98358

http://www.maplin.co.uk/solar-powered-1 ... ger-223251
Richard

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smithskids
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Re: Alternator failure

Postby smithskids » Wed Jul 10, 2013 9:08 am

me also, one on each car except morris 8 is 6 volts. Does any one know if you can get a 6v solar top up panel? :) smithskids.

bmcecosse
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Re: Alternator failure

Postby bmcecosse » Wed Jul 10, 2013 2:32 pm

The standard solar panel works perfectly well on a 6 volt battery - I use them to charge up 4.5 volt battery packs for my railway lamps. There's NO chance of overcharging ...
But solars are designed to just keep a car battery topped up when the car is not being used for some time - the charge gained (especially in winter) will be negligible on a day to day basis.
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Dru
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Re: Alternator failure

Postby Dru » Wed Jul 10, 2013 2:42 pm

sorry to drop out of the conversation there! -just been running a narrowboat up the Severn from Bristol to Sharpness... the boat has just had solar panels added, v handy for keeping the fridge going.

...anyway, I shall tinker with the alternator some more, but I was in a hurry to get the car up and running for some journeys that need making just now. Shall examine rectifier, regulator etc at meisure after I've found out how to test them :) -thank you for helpful suggestions!

rayofleamington
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Re: Alternator failure

Postby rayofleamington » Wed Jul 10, 2013 2:46 pm

The standard solar panel works perfectly well on a 6 volt battery - I use them to charge up 4.5 volt battery packs for my railway lamps. There's NO chance of overcharging ...
But solars are designed to just keep a car battery topped up when the car is not being used for some time - the charge gained (especially in winter) will be negligible on a day to day basis.

Anything up to 2w panel isn't an issue for overcharging..

However if you've got a 15w panel, then it would (eventually) overcharge a large 12v truck battery, let alone a 6v battery.

I'd never really thought about using the solar panels in winter on a daily driver car* as I only use mine on cars that are laid up.. however it's not a bad idea. The panels say not to leave connected when the car is running (although they are diode protected ) but it wouldn't be hard to wire it up in a way that's disconnected when the car is running.


* I've tended to trickle charge the car overnight if it's getting discharged with high loads and no/low speed driving.
Ray. MMOC#47368. Forum moderator.

Jan 06: The Minor SII Africa adventure: http://www.minor-detour.com
Oct 06: back from Dresden with my Trabant 601 Kombi
Jan 07: back from a month thru North Africa (via Timbuktu) in a S3 Landy
June 07 - back from Zwickau Trabi Treffen
Aug 07 & Aug 08 - back from the Lands End to Orkney in 71 pickup
Sept 2010 - finally gave up breaking down in a SII Landy...
where to break down next?
2013... managed to seize my 1275 just by driving it round the block :(

katy
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Re: Alternator failure

Postby katy » Wed Jul 10, 2013 4:21 pm

...and the alternator is whining again.


That's usually an indication of a faulty rectifier.
Talk slow, think fast!

Dru
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Re: Alternator failure

Postby Dru » Wed Jul 10, 2013 5:33 pm

thank you, Katy- that is useful to know

LelandGordon
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Re: Alternator failure

Postby LelandGordon » Fri Nov 22, 2013 10:20 am

irmscher wrote:what about a solar kits charger with the dynamo pretty cheap now

Yes solar charger are bit cheap but lot more effective..Even I am using similar set up and very much satisfied with the outcomes.


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