Altinator Issue
Thread Starter
Race Director
Joined: Feb 2006
Posts: 12,239
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From: Chino CA
Altinator Issue
I have noticed that I to have rev up my engine to get the altinator to "kick-in"...I think there's a wiring trick to get it to charge even at low RPM's....?????
Race Director
Joined: May 2006
Posts: 16,528
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From: Dayton, Ohio
What wires are in the 2wire connector on your alternator ?
Hey Sixfooter if the brown exciter wire measures 2.2 ohms in 10" do you then multiply 2.2 x the actual length of wire to come up with the ohms needed for the exciter wire ?
Hey Sixfooter if the brown exciter wire measures 2.2 ohms in 10" do you then multiply 2.2 x the actual length of wire to come up with the ohms needed for the exciter wire ?
Thread Starter
Race Director
Joined: Feb 2006
Posts: 12,239
Likes: 19
From: Chino CA
I'm at work and can't see the wires right now....anyone have some pictures or a drawing of how it "should" be wired ???
Sorry I wasn't prepared to really answer the question....:o
Sorry I wasn't prepared to really answer the question....:o
Race Director
Joined: May 2006
Posts: 16,528
Likes: 53
From: Dayton, Ohio
But its pretty simple , on the back of the alt should be 1 heavy red lead,
on the top is a 2 wire plug,the wire closest to the drivers fender should be a small brown/white wire,the other wire should be a heavy red wire.
If your car has had the 2 wire pigtail replaced the colors could be different.
When you get home pull the 2 wire plug and check the brown for 12 volts with the ignition turned to the ON position. If you dont have voltage thats the problem.
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Burning Brakes
Joined: Oct 2002
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You got me all confused now.I ran out to the container and looked at my wiring the brown wire is towards the drivers fender,The other wire is a black with white tracer.
I hooked test light to the brown turned key on = nothing
I then tried the black wire = power on all the time.
As far as I can tell the forward harness is the original,I have it opened up right now to wire in relays,replaced horn relay in the process also,just looked and see the black wire splices into another then runs thru a fuseable link which seems to me would be the hot wire ? (( Roger))
So back to the two wires on the alternator,my car starts fine, battery is being charged I have noticed also that I need to rev my motor to get it charging, but have not had any issues because of this.
So lets hear some ideas on this ? problem ?
I hooked test light to the brown turned key on = nothing
I then tried the black wire = power on all the time.
As far as I can tell the forward harness is the original,I have it opened up right now to wire in relays,replaced horn relay in the process also,just looked and see the black wire splices into another then runs thru a fuseable link which seems to me would be the hot wire ? (( Roger))
So back to the two wires on the alternator,my car starts fine, battery is being charged I have noticed also that I need to rev my motor to get it charging, but have not had any issues because of this.
So lets hear some ideas on this ? problem ?
Race Director
Joined: May 2006
Posts: 16,528
Likes: 53
From: Dayton, Ohio
You got me all confused now.I ran out to the container and looked at my wiring the brown wire is towards the drivers fender,The other wire is a black with white tracer.
I hooked test light to the brown turned key on = nothing
I then tried the black wire = power on all the time.
As far as I can tell the forward harness is the original,I have it opened up right now to wire in relays,replaced horn relay in the process also,just looked and see the black wire splices into another then runs thru a fuseable link which seems to me would be the hot wire ? (( Roger))
So back to the two wires on the alternator,my car starts fine, battery is being charged I have noticed also that I need to rev my motor to get it charging, but have not had any issues because of this.
So lets hear some ideas on this ? problem ?
I hooked test light to the brown turned key on = nothing
I then tried the black wire = power on all the time.
As far as I can tell the forward harness is the original,I have it opened up right now to wire in relays,replaced horn relay in the process also,just looked and see the black wire splices into another then runs thru a fuseable link which seems to me would be the hot wire ? (( Roger))
So back to the two wires on the alternator,my car starts fine, battery is being charged I have noticed also that I need to rev my motor to get it charging, but have not had any issues because of this.
So lets hear some ideas on this ? problem ?
Your black to black spice should run to an orange fusible link , that circuit runs through the ammeter.
The 24 gauge brown- it should be hot with the key on. You could try backing up from the connector and probing the wire to see if its hot. The first place the wire has a connection is the bulkhead connector.
Once the wire goes through the bulkhead it turns into a 12 brown which powers the wipers and radio, so if the wipers work the 12 brown is hot.
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,114
From: Crossville TN
I think one of the (three) diodes in the regulator pack is bad. You can replace the alternator of disassemble it and check out the diode packs to see if one is bad. Alternator/starter repair shops and auto parts stores like NAPA can sell you just the diode packs.
Race Director
Joined: May 2006
Posts: 16,528
Likes: 53
From: Dayton, Ohio
Start the car but don't rev it.
Ammeter should be discharging.
(2 wire plug still in the alternator.)
Attach the alligator clip of your test light to the hot stud on the back of alternator.
Now push the probe end down inside the 2 wire plug touching the brown wire connector.
That should tell the alternator to start charging.
Team Owner
Joined: Jul 1999
Posts: 65,492
Likes: 230
From: Orange Park Florida
Wiring practices, and color codes, and even gauges changed over the years, sorry but I can't reference all of the variations... but sharks mainly came with alts having the regulator inputs arranged -- and as such, if you look at it from the backside/drivers angle....the MOST CLOCKWISE pin on that alt regulator is always HOT...12 volts under all conditions of the ign switch...
flip on the swith to the start/run position....then and ONLY then the other pin will show a slight voltage....engine is NOT RUNNING...
BUT IF you have a idiiot light it should glow red....many/most? sharks did not have a idiot light and instead used a steel core resistor wire to sub the correct resistance into that charge signal circuit side of the reg....
So when you stare the engine that LEAST clockwise pin will go high to damn near the output at the alt stud......
anything else is a wiring error.......
Every GM car of the era from A to B body, shares this basic wiring concept....I not a expert on F and G body...sorry...
flip on the swith to the start/run position....then and ONLY then the other pin will show a slight voltage....engine is NOT RUNNING...
BUT IF you have a idiiot light it should glow red....many/most? sharks did not have a idiot light and instead used a steel core resistor wire to sub the correct resistance into that charge signal circuit side of the reg....
So when you stare the engine that LEAST clockwise pin will go high to damn near the output at the alt stud......
anything else is a wiring error.......
Every GM car of the era from A to B body, shares this basic wiring concept....I not a expert on F and G body...sorry...
