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AB
10th April 2012, 03:16 PM
Had a scary ride home with no alternator and battery down to 6 volts from SA yesterday.

Did some tests today and only 0.15V coming from the rear cord. I thought mud might have ruined the alternator but after looking around I saw a spark and noticed the rear cable feeding the crank battery had worn and rubbed onto the metal A/C hose.

Using a multimeter whilst car on confirms only 0.15V coming out. I'll take the alternator out this weekend but what do I look for?

Is the alternator completely ruined, is their a fuse or something inside the alternator at all to replace?

Any help appreciated!!!!

Yendor
10th April 2012, 03:39 PM
If you only have .15v on the large White wire at the back of the alternator you have blown a fusible link.

You should have at least have battery voltage on the large White wire.

Check your fusible link, if this is blown replace it then recheck alternator output.

AB
10th April 2012, 03:59 PM
Thanks Rod, where is this fusible link?

The reading above was directly off the back of the alternator, the bolt thread thing that comes out the back where the white wire gets connect to which goes to the battery.

Yendor
10th April 2012, 04:18 PM
It is in the fuse box near the main battery.

It will be a large fuse, around 60-80amps.

That large White wire on the back of the alternator as you said "goes to the battery" this should have the same voltage reading as across your battery (around 12 volts).

AB
10th April 2012, 04:28 PM
Yeah all those are fine, black IGN fuse, the glow and the three green and brown ones are all ok.

The volt reading when the battery is charged at the white wire near the back of the alternator is ok at 12 volts.

When engine started it drops to 11.7 volts and doesn't rise.

When engine running I disconnect the white wire off the alternator and the reading just off the bolt at the end of the alternator (white wire not connected) is 0.15V.

I'm thinking the actual alternator is dead as it is not producing zip??

Maybe either the short did something or mud got inside and ruined it but it looks super clean from where I can see.

Yendor
10th April 2012, 04:55 PM
Ok,

You should never disconnect the battery or alternator while the vehicle is running.

What can happen if you do this is, the system voltage can rises so high that it blows all other electrical items.

As long as your alternator/battery warning light in the dash still works then yes your alternator is stuffed, more then likely blown the power diodes in the rectifier.

AB
10th April 2012, 04:57 PM
Thanks Rod, I'll know next time....Jeesh Ive done that about a dozen times today too!!!!

Ok, so I have an auto elec mate down the road. Is it worth taken it off and give to him or buy another one.

I can get the same one again with trade discount for $300....

Thanks for your help mate!!!

Yendor
10th April 2012, 05:14 PM
It's only a problem if the alternator is working.

I have been out of the game for about 10 years so I can't really comment on prices.

I would have a talk with your auto elec mate, he would be the best one to advise on that.

Depending on parts availability it might be better to get a new one.

dan&tamspatrol
10th April 2012, 05:15 PM
take it to the mate that way you will know for sure

AB
10th April 2012, 05:20 PM
Thanks Lads, I'll let you know the outcome....Can't wait to take it out either....Pain in the....

Yendor
10th April 2012, 05:28 PM
LOL.....It can't be any worse then a ZD30 with dual batteries.

growler2058
10th April 2012, 05:29 PM
OK mine when ignition was on but motor not running, my battery/alt light wouldnt come on as it usually would and those of you at loveday seen ol Aggie no go. And my glow plug indicator light only came on for 1/4 of a second. By the time I got home all seemed good, ie when i shut her down, then turned the ignition on without cranking my battery/alt light was back on, then upon starting went off straight away as per normal function. So maybe mine and maybe yours also just needed a good clean out??? Maybe the brushes could be stuck like that Yota drivers????? Wishful thinking maybe??

AB
10th April 2012, 05:33 PM
Not sure mate but I had a scary ride home...lol....I just had enough volts to run the brake lights and had to get home before dark and before it poured rain as lights and wipers would suck it dead.

I'm going to pull mine out this weekend and have a looksie.

Maxhead
10th April 2012, 05:38 PM
OK mine when ignition was on but motor not running, my battery/alt light wouldnt come on as it usually would and those of you at loveday seen ol Aggie no go. And my glow plug indicator light only came on for 1/4 of a second. By the time I got home all seemed good, ie when i shut her down, then turned the ignition on without cranking my battery/alt light was back on, then upon starting went off straight away as per normal function. So maybe mine and maybe yours also just needed a good clean out??? Maybe the brushes could be stuck like that Yota drivers????? Wishful thinking maybe??


How was the Yota driver, poor blokes were under the vehicle for most of their time out there......

growler2058
10th April 2012, 05:56 PM
How was the Yota driver, poor blokes were under the vehicle for most of their time out there......

After Fixer got it out for them Tony gave it a shake up and the brushes were stuck in whith sh1t so he cleaned em up and they were back in aaction

Maxhead
10th April 2012, 06:07 PM
After Fixer got it out for them Tony gave it a shake up and the brushes were stuck in whith sh1t so he cleaned em up and they were back in aaction

On ya fixer, showed those Toyo boys,,,LOL.

Thats why after every session I high-pressure washed the engine bay as much as possible but still had bit of crap in the radiator as she ran hot most of the way home..

AB
14th April 2012, 10:43 AM
Well finally got the alternator off this morning and it looks super clean so I'm thinking the short blew something.

Now that It's out, does anyone know of any tests or tricks I can do or something I can check out myself to maybe fix before giving it to an auto elec???

Always keen to learn and fix things myself...lol

growler2058
14th April 2012, 10:46 AM
Need to check the brushes are not stuck in mate like the crooza at loveday was

97_gq_lwb
14th April 2012, 11:42 AM
Well finally got the alternator off this morning and it looks super clean so I'm thinking the short blew something.

Now that It's out, does anyone know of any tests or tricks I can do or something I can check out myself to maybe fix before giving it to an auto elec???

Always keen to learn and fix things myself...lol

Their is a pretty good guide in the manual on how to test it all even has pics lol

AB
18th April 2012, 08:46 AM
Ok, alternator is all fixed.

The problem was after it shorted out the brushes heated up and wouldn't expand so they needed to be replaced.

97_gq_lwb
18th April 2012, 10:10 AM
Mine is still going strong after cleaning the crap out of the worn out brushes i should replace them sometime soon and the bearing lol.
Sounds like this thread could save a few people from wasting their money on a new alternator.

Yendor
21st April 2012, 04:24 PM
Ok, alternator is all fixed.

The problem was after it shorted out the brushes heated up and wouldn't expand so they needed to be replaced.

Good stuff, that was a cheap fix.

We should of gotten you to have a look at what the bearing numbers are while it was apart.