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Guest Message by DevFuse
 

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?'s about my alternator...


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9 replies to this topic

#1 misledxcracker

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Posted 19 June 2007 - 12:02 PM

(BTW I do trust my volt gauge, just not the oil... :lol:)

My alternator had been acting weird lately. The volt gauge would sit at 10 or so, the battery checked out on the meter around 12.something, and the alternator at like 17.something...

Finally last night, the thing died coming home from work.... $79 to tow the car 2 miles. Egads.

I take the alternator to the auto parts store (schmuck's) and they tested the alternator TWICE, and it was FINE. The lady was even nice enough to print me out the test results, and it all checked out OK.

Then I noticed the hot alternator wire connector, it was WHITE like it had been overloaded :-\ So, I replace the connector with a fresh one, and all is well now!

What gives? So my problem was a connector all along? Why would the meter say 17 volts.... I checked voltage with the positive meter lead on the alternator, and the negative on the negative battery terminal. Maybe that was why it said 17?

BTW the alternator is on warranty. Remanufactured OEM alternator, done at a local electric shop.

Damn, I hate when a $2 "fix" really costs much more :-\

#2 misledxcracker

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Posted 19 June 2007 - 01:09 PM

Bump... I'm still paranoid about it... Dont want another $80 tow bill tonight after work :lol:

Is there anything I should be worried about?

#3 Bucky92

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Posted 19 June 2007 - 01:23 PM

The white connectors get brittle with age...they get all gooie and can short and just reek havok on your electrical system...( very common with the XT6s BTW)...adding a couple inches of new wire and a new connector usually fixes the problem..Double check the usuals also..wires grounds battery...

Just on of the options...what is your volts reading right now..back to 12V+ ??

#4 misledxcracker

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Posted 19 June 2007 - 01:24 PM

Usuals have been checked, and cleaned. The white connector wasnt the one that went on me, it was the hot connection.

Reads 12 now on the volt gauge, like normal. I had to use my mom's Civic battery, start the car, then swap batteries when it was running (I know, I know!)

It charged the before-flat battery, I turned the car off, it started right back up, and back at 12V it went.

I'll try to start it right now, and see what it does.

#5 nipper

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Posted 19 June 2007 - 01:32 PM

Ill try this again, last time the site threw up on me :(


In a word, probably not.

DIrty ,loose connections can cause overloads and fires. There is an increased resistance across the connection. The Altenator is responding to this by cranking out the volts and amps to try to bridge this resistance.

This is what an altenator may do if the battery is internally shorted. SInce the higher resistance was local, it shouldnt be a problem.

What i would do is check the last few inches of that lead and make sure its pliable. If its not you may want to replace it, as an over heated wire is not as effecient, and can cause the same probelem.

nipper

#6 grossgary

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Posted 19 June 2007 - 01:41 PM

nippers last sentence. i would add to check the battery terminals while you're at it. it isn't all the uncommon for battery or alternator failure to follow a few months after having electrical issues. i've had multiple "come backs". in other words, a friend or family member has a vehicle that has horrible connections or terminal end links at the battery. replace those and all is good. then the battery dies 2 months later. or replace a bad battery. then a few months later the alternator dies....bad connections over work the alternator and don't sufficiently charge the battery, lessening it's life. i'm fairly picky about my own connections now. i install new alternator plugs as soon as i get an older vehicle, i have a bag of them. battery terminal end links, i replace those frequently as well.

#7 misledxcracker

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Posted 19 June 2007 - 02:03 PM

Thanks Nipper and Gary, I get it now... Yeah, the wire is pretty bad, but I took some wire brush and electronics cleaner to it, the wire looks good now. I also put a new ring connector for the hot wire, yet that plastic boot was melted, and broke on me.

When I had tested it with a meter, it said it had AC current going through it. Maybe my meter is crap, I dont know, but the three tests passed fine on it.

They did say at the auto parts store that the alternator was just fine, but the plastic piece thats under the hot wire bolt is all burnt :eek: So I guess it was just because of the bad wire: The alternator overloaded, but at the most only 45 minutes to an hour. I also have that warranty in case of another REAL failure :lol:



#8 nipper

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Posted 19 June 2007 - 02:12 PM

One other word of advice........

Get AAA. It pays for itself, and great peace of mind.


nipper

(and Grossgary. .... STOP FOLLOWING ME!!!)

hehehehehehe

#9 Bucky92

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Posted 19 June 2007 - 03:24 PM

One other word of advice........

Get AAA. It pays for itself, and great peace of mind.



I second that notion...even though I still havent gotten it yet

#10 Cougar

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Posted 19 June 2007 - 04:24 PM

Finding a burned alternator output connection is pretty common. This just shows how important it is to have clean and correctly tighened connections at the alternator and the battery. A lot of current passes though the connections and any resistance between the connections will make things heat up due to the high current passing through.

The other posters covered this problem well. I will just add that one quick way to see how well made your connections are is to measure the voltage across them while the system is running. By placing the voltmeter leads across the alternator output lead and the positive battery post you should see close to zero volts if things are good. If there is more than 0.1 volts across the wiring with a good load on the system then connections should be looked at. Using your meter to measure across each connection will show up the bad spot. The main battery ground lead should be looked at also doing the same procedure on it.

One other thing mentioned by the OP is about the AC voltage the meter showed. Since the alternator was forced to run at max output the DC ripple will be higher. You should see different results now after things are fixed. You may also have a meter that doesn't seperate the DC component in the AC mode. If you measure a battery in the AC mode and you show something close to the battery voltage then you need to remember that characteristic with that meter. You can eliminate the DC by place a capacitor in series with one of the probe leads, if you need to.




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