Voltage regulator problem

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jarhead
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Voltage regulator problem

Post by jarhead »

I have an early 66 so the plug to the voltage regulator is different than later models. I had the alternator refurbished and after installation, there was unregulated flow noted on the ammeter. So I got a "late 66" VR from Dean. I had to take the wires out of the plug to attach, since they were different.

But now I'm not charging right. it will give pos charge when rpm above 2000. With lights on it is discharging regardless of rpm. I have been over the wiring diagram about 50 times, and I'm pretty sure it is wired correctly. There is one wire on the VR "L" which doesn't seem to do anything? Any electrical gurus have suggestions?

Out of frustration I put the old VR back in and it is back to the former problem of unregulated flow. Before I give up and get an aftermarket alternator with internal VR, is there anything I could be missing or doing wrong?
Lee
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msampsel
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Re: Voltage regulator problem

Post by msampsel »

What is the voltage reading on the battery with the unregulated flow?
Ditto when the lights are on and off.
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Re: Voltage regulator problem

Post by Nissanman »

The "L" terminal is for an "IGN" or "CHARGE" Lamp i.e. idiot Lamp.
Not normally used in our cars since they came with an ammeter to indicate Charge/Discharge.
In case you haven't seen it, here is the relevant section of wiring: -
66-67 Charging circuit.jpg
The full Wiring Schematic is available here: -
http://www.311s.org/pmwiki-311/pmwiki.p ... ngDiagrams

As suggested do some voltage readings and quote what current readings you are seeing on the Ammeter for the various conditions :idea:
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jarhead
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Re: Voltage regulator problem

Post by jarhead »

Update. I ran some numbers with new and old VR. All are voltage numbers at the battery.

New VR
Idle 12.45
2k rpm 12.65

Lights on
Idle 12.20
2k rpm 12.30

Old VR
Idle 14.20
2k rpm 16.50

Lights on
Idle 13.50
2k rpm 16.0

Thoughts? Appears to me that neither is working as it should.
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Re: Voltage regulator problem

Post by K1200 GT »

Looks like the new one isnt charging at all, unless it will get to 13.5- 14 Volts. The old one at 16 Volts is over charging and could start burning things up.
Why dont you get an electronic voltage regulator. love mine and had for 5-6 yrs. maybe. :)

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msampsel
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Re: Voltage regulator problem

Post by msampsel »

Solid state is a good plan for a vreg. One was mentioned at rock auto is while ago.

Good news is the alt is charging.
The VREGs from Dean are 65 - 70 cars?
So I do not follow the early reg reference.
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Re: Voltage regulator problem

Post by JT68 »

jarhead wrote:I had my early 66 alternator rebuilt for about $100. The problem was finding a voltage regulator for early plug. Can't find them anywhere.
Can you elaborate on this? I've had lots of early cars over the years and don't remember this detail at all. Aside from the early cars that used screw terminal connections, I only remember a standard 6 terminal plug.

Its possible I forgot, or maybe yours is modified? Either way would be very easy to update the connector for the regulator. There are just 5 wires and if all the color codes match, it will work perfectly. Ign,Alt+. Ground,Neutral, Field.

If they are messed up it won't charge, will overcharge, (or will melt)

Solid state regulators are fine, but a standard regulator should work fine too..j
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Re: Voltage regulator problem

Post by jarhead »

JT68 wrote:
jarhead wrote:I had my early 66 alternator rebuilt for about $100. The problem was finding a voltage regulator for early plug. Can't find them anywhere.
Can you elaborate on this? I've had lots of early cars over the years and don't remember this detail at all. Aside from the early cars that used screw terminal connections, I only remember a standard 6 terminal plug.

Its possible I forgot, or maybe yours is modified? Either way would be very easy to update the connector for the regulator. There are just 5 wires and if all the color codes match, it will work perfectly. Ign,Alt+. Ground,Neutral, Field.

If they are messed up it won't charge, will overcharge, (or will melt)

Solid state regulators are fine, but a standard regulator should work fine too..j

I was referring to the plug. Different shape so that the aftermarket VR won't be plug and play. Newer ones are rectangular. Mine was square. I just clipped and used individual male/female connectors. Still not sure why the new one isn't working correctly. I'm going to try again with another VR.
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Re: Voltage regulator problem

Post by JT68 »

I'll be glad to send you a rectangular connector (6 terminals) for free and a known good regulator. Simple enough.

Its also a good idea to have a nice ground wire go from the alternator case down to the frame or connecting to the neg battery terminal. (10 ga is perfect). J
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Re: Voltage regulator problem

Post by spl310 »

Quick, take JT up on his offer
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jarhead
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Re: Voltage regulator problem

Post by jarhead »

JT68 wrote:I'll be glad to send you a rectangular connector (6 terminals) for free and a known good regulator. Simple enough.

Its also a good idea to have a nice ground wire go from the alternator case down to the frame or connecting to the neg battery terminal. (10 ga is perfect). J

Wow. That is awesome. Thanks.
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Re: Voltage regulator problem

Post by msampsel »

JT68 wrote:I'll be glad to send you a rectangular connector (6 terminals) for free and a known good regulator. Simple enough.

Its also a good idea to have a nice ground wire go from the alternator case down to the frame or connecting to the neg battery terminal. (10 ga is perfect). J
JT, My carbs don't look right, and do not say solex on them. Thought maybe you'd be happy to send some for free :lol: :lol: :lol:
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Re: Voltage regulator problem

Post by JT68 »

LOL! He's a very funny guy!!
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Re: Voltage regulator problem

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Whenever someone I'm working with on the phone asks me "Is there anything else I can do for you today?" I always say "Why yes, can I get the winning lottery numbers please, and not for last week?" This always gets a laugh no matter how the rest of the conversation went :-)

So JT... got them numbers?
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