Hi all, was cleaning the wires that go to the alternator (71 olds 442), can you tell me what they are for ? (see first pic). The wire with the big connector is blue and have power with ignition ON,
and the green one also have power with ignition ON, they were both disconnected. I thought I found the wires for the oil pressure switch and engine temp, but if they have power with ignition ON, I'm not that sure what do you think ?
The second picture I have the molex connector with the 2 wires, these were ok...well almost, until I pull them !!

And is this the correct alternator for a 71 442, no AC. I see alternator with external or internal regulator..this one is with internal regulator I think...right ?

Thank you all

 

The two wires in the first photo appear to be for the oil (blue) and temp (green) switches for the idiot lights. No Olds came with a chrome alternator, so that's not a factory piece. A real 1971 442 came with an openface, "diamond back" 10SI internally-regulated alternator. All other Cutlii came with the 10DN externally regulated alternator. The aftermarket pigtail on that alternator also is not OEM.

 

Make sure you tin those bare wire ends before crimping or soldering them. It might be a good idea to cut them back a bit too so there's no corrosion on them.

 

Absolutely, thanks for your reply and for the big red wire on the back of the alternator and on the pigtail, should I use 12gauge wire or 10 ?? Actually, the one on the pigtail is about 12gauge but the rest of the wire looks like 14 or 16 gauge.
Can't see it in the wiring diagram.

 

If these wires are for temp and oil idiots lights, to test the lights, if I ground the wire with ignition ON, I suppose the light will be ON in the dash right ? But I have 12V with ignition ON on the wires, is it suppose to be like that ?

Thanks again Joe for passing on your knowledge.

 

I'd use 10 gauge for the charge wire. Actually, for the charge wire you probably don't want to tin the end or solder it. Just crimping will do. Make sure you are using a good crimping tool.

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Do you mean the wire that is screw on the back of the alternator ? I have a 10 gauge wire, but the exterior is in silicone not plastic wil it be ok you think ?

Thanks

 

The circuit is powered on the other side of the idiot light, so yes you will see open circuit voltage on the wire. This is the problem with low-impedance voltmeters. If you are worried about it, use a fused jumper to connect to ground. The current shouldn't be enough to blow the fuse.

 

Just did the test with both wire directly grounded and both idiot lights are ON with ignition ON...yeeeessss.

Thanks Joe.

 

Just replaced the alternator wiring on my friend's 71 442 and now the GEN light is ON with ignition OFF...even the radio is ON !!!! Tried to start the car and the new battery is dead.
Maybe the problem was there before replacing the wires, because the old battery was already dead 2 days after he brought me the car from storage, I probably did not notice the Gen light ON.
About the 2 wires that goes on the back of the alternator, correct me if I'm wrong, the brown wire is connected to
field #1 and as voltage only with igniton ON, the red is in #2 field and as constant battery power. I read that if I unplug these two wires and
the light goes OFF (again with ignition off), the problem would be the diode inside the alternator (it as internal regulator), any advice please.

Thanks

 

Some after market alternators (like mine) are designed to be wired using only the charging wire bolted to the back. If i were to plug in side plug on my alternator, it would cause the issues your describing. I simply leave the plug out and tucked behind the alternator. Try unplugging the side plug and run the car. Check to see if its charging with a volt meter, and if your other issues go away. Hope this helps!

 

Never heard of this one, maybe your right, I'll check that

Thanks

 

Hi again, still have my GEN light problem, it's ON with key OFF and radio is ON also. Can somebody tell me if this is correct for this alternator (internal regulator).
With the connector on the back of the alternator disconnected and with key OFF, I get battery voltage on red wire and nothing
on the brown wire. With key ON I get battery voltage on that brown wire.
With the connector still disconnected, I get battery voltage on both pin #1 and #2 on the back of alternator with key OFF.
And yes when I disconnect the connector the idiot light and the radio go OFF.

I'm lost, don't know what to check, all I did was cut and replace a few inch of the 2 wire, the connector and a new wire from horn relay to back of alternator.
Any help will be appreciate.
Thanks

 

Hi, just a little follow up on that alternator problem, brought it to a repair shop and they said the white part inside ( I think the regulator) was not the
correct one, and something was by-passed with a wire (diode ??) .They did the repair and now no more GEN light (of course except with ignition ON) and radio is off.

So I had battery voltage on the 2 connectors on the side of the alternator (field#1 et #2) , so current was going into the ignition switch and to fuse box and eventually to the radio !!
Now I don't have voltage at the 2 connectors on the side of the alternator (field#1 et #2) !
Another problem solved !
Thanks to all for your help