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Discussion Starter #1
Hi guys, I am posting on the right forum this time

I started the car this morning, once again when I start the car the voltmeter gauge shows about 14V. After it iddles for a few seconds it starts going down.

With the car iddling at 900 rpm, I measured the big red wire on the alternator to ground and I am getting 8.4 Volts. It looks to me that the alternator is not charging.

Before I spend the money on a new alternator, which I wanted to do at some point to go to a 140 amp unit, how do I make sure it is the alternator and not the Voltage regulator?

I have read in a previous post that I can "paper clip" the F & 3 terminals on the regulator and then measure again. Is this the right procedure, and do I measure at the alternator again, or at the battery at the trunk, or does it matter?

I have a remote starter solenoid and the other day when we put the motor back together we used a wrench on the solenoid to kick the car over, I wonder if this ruined my regulator.

Appreciate your help, thanks.
 

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Discussion Starter #3
I measured the blue wire with the plug out of the alternator and the key in the ON position and I am getting 5.6V, not even close to 12.
Does this mean that the regulator is bad?
Thanks
 

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<BLOCKQUOTE>quote:</font><HR>Originally posted by yanniz:
I measured the blue wire with the plug out of the alternator and the key in the ON position and I am getting 5.6V, not even close to 12.
Does this mean that the regulator is bad?
Thanks
<HR></BLOCKQUOTE>

Blue wire is the alternator field wire. Was the engine running when you got the 5.6 volts? With the engine running the alternator should have greater than 12 volts.
 

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Discussion Starter #5
The key was in the ON position but the engine was not running.
Should I measure the blue wire with the engine running and the plug out of the alternator?
I know that the big red wire on the alternator only has 8.something volts when the engine is running.
Thanks.
 

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8V on that wire is really low. How are you starting the car since that battery must be completely dead?

The voltage on that blue wire could be correct. Remember, the field is used to regulate the voltage output. Changing the field voltage will vary the alternator output so the field won't be just running at battery voltage. There's a coil going to ground in the regulator hooked up there so it's probably causing that voltage to appear.

And yes, jumper the F to the battery terminal to see if the alternator is OK. Don't do it too long and have the meter connected when you do it. It should not matter where you measure. If you measure a different voltage at the battery than the alternator you have wiring problems.

What are the voltages at the other terminals on the regulator when running? Look through the post John listed and tell us what you find.

Personaally, I'd bet on it being a dirty contact in the mechanical regulator.

Peter
 

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<BLOCKQUOTE>quote:</font><HR>Originally posted by yanniz:
The key was in the ON position but the engine was not running.
Should I measure the blue wire with the engine running and the plug out of the alternator?
I know that the big red wire on the alternator only has 8.something volts when the engine is running.
Thanks.
<HR></BLOCKQUOTE>
Yes if you do it that way the engine should be running. Suspect you will only see around 8 volts out of that (blue) wire. See what the chain auto stores say when they test the alternator. Almost looks like a diode problem inside the alternator.
 

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Discussion Starter #9
Well, I ordered the Powermaster 140 amp one wire unit today.
Is it going to be a pain to convert? I already noticed that it comes with a V belt pulley, I have single-belt surpentine so can I use my pulley of my old alternator?
Thanks
 

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Discussion Starter #11
Already did. Did not answer my questions about my pulley and what it will take to convert though! I am assuming the new unit comes with instructions, but that will not address the pulley question.
 

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Yes, you should be able to use your old pulley, if for some reason not, we'll figure it out with ya

------------------
'71 468 Street/Strip Monte Carlo 3950lbs, 9.8:1, 3.55's, 11.46 @ 117, 7.29 1/8 mile
1.62 60'
 

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Discussion Starter #14
Ok, I got the Powermaster 140 amp.
How do I wire it as a wine wire unit. I am assuming that I will take a big cable from the big post at the back to the battery positive on the remote solenoid.

What do I do with the voltage regulator and its wires? How about the horn relay and its wires (is the horn relay tied in to the regulator or alternator?)

Thanks guys

Edit: I should have said that there is already an 8 gauge wire going from the Horn relay to the positive battery terminal, we added that when we did the resto.
So, could it be as simple as running a cable from the alternator to the battery terminal on the remote solenoid? What gauge should I use?

Thanks

[This message has been edited by yanniz (edited 07-18-2002).]
 

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"I should have said that there is already an 8 gauge wire going from the Horn relay to the positive battery terminal, we added that when we did the resto."

Run an 8 gauge from the alternator B+ output to your horn relay.
 

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Discussion Starter #16
Do I need to worry about the wires in the voltage regulator et cetera? Don't care about the alternator light in the car.

8 gauge seems kind of small for a 140 amp unit, doesn't it?

Thanks
 

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Discussion Starter #17
Is 8 gauge going to do it? I got some 4 gauge last night, and the connector is just too big to fit on the remote solenoid lug.
Distance from alternator to the remote solenoid, 6 feet.
thanks
 

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Discussion Starter #18
Ok guys, let me try another question.
Can I run 2 10 gauge cables from the alternator to the solenoid, instea of one 6 gauge or whatever?
Thanks
 

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Yanniz
Running it to the horn relay is just fine. If you want to run it to the battery or the solenoid that's fine also. Go for the easy way.
 
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