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Discussion Starter #1
Alrighty... the other evening, I noticed the headlights going dim and the wipers slowing down... Figuring it was because the battery wasn't getting charged, I did the old backyard trick of pulling the battery cable while the car was running to see if it the alternator was working or not. The car died so I went and got a new alternator for it, but it's still doing the same thing. I checked all the connections and everything looks alright except that where the hot wire connect to the alt., there's a wire coming off of that that isn't hooked to anything, and there's nothing in the general vicinity to hook it into... Anywho, I can't figure it out... Am I overlooking something? Is there some sorta little tricky thing going on here that you guys know about and I don't? And, anyone know what that other wire goes to? By the way, this is a 74 260Z... and I don't have a voltmeter yet, so keep that in mind.

Thanks a million for all your help!

Shayne
 

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Chances Are...

Your alternator was fine. The regulator goes out, and you get no alternator output, or very little unless you rev the heck out of it...
There is a shorting test in the FSM and most of the other manuals, as well as being detailed in the archives,.
That is the troubleshooting step to determine if the alternator works. Basically you supply 12v to the field and see if the thing puts out voltage.
Failing that, you pull both parts, take them to the local parts chain, and have them tested free of charge.
My 260 lost it's regulator after a hot wire shorted to ground. A week later my 76 Fairlady lost the regulator (from old age, I suppose). When the alternator goes bad you usually can find a physical sign: Diode falling out the back... Lokks up when you spin it because the bearings are bad... chunks of the brushes rattling around inside...

The regulator is more insidious... It can let the alternator charge you just enough to run along on the freeway for weeks, but in three hours of stop-n-go after dark, it dies... That's what the 76 was doing. Regulator should be under $30, and alternators were $19 or 24 at Auto Zone last month.
 

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Discussion Starter #3
wulp...

I suppose I'll go tomorrow and get a regulator... I did get the alt. at auto zone, about 25 bucks. Guess it's at least one thing I don't have to worry about falling apart anytime soon! Of course, knowing my luck.....




Shayne
 

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Re: wulp...

btw that little wire not attached to anything is likely for the condenser on the alt. Should be a blue or black wire running from the output post on the alt -through the condenser which is then attached to the ground terminal 'E' of the alternator. If this is just a daily driver and you are not concerned so much with originality you might want to consider converting to an internally regulated later (78 or later) model Z alternator. Or there was a post somewhere on the forum about converting to a single wire alternator. Search archives for that one. When you say you don't have a voltmeter, are you referring to the one in the car or a tester?
 

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Discussion Starter #5
aaaaaahh...

A voltmeter tester thing... like at the parts store. Well, actually, I don't have the one in the car yet either, I've done quite a bit of work on this thing... one thing at a time. Right now, none of the gauges work... I suppose I'll cross that bridge when I get there. I'm more focusing on the engine and mechanichals right now.

Thanks

Shayne
 

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Re: aaaaaahh...

I seem to remember the 260 still has the ammeter in the dash. I guess it used a shunt up under the hood also. Might want to make sure that wiring is correct too. If gage has been pulled out perhaps the shunt was bypassed or disconnected. That could have something to do with the charging problems.
 
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