Alternator replacement questions

[Viperwolf1]

No it is reading backwards

At the plug I go :
S. 12.6 volts green/ red tracer
F 0v. Orange wire
A 0v. Yellow wire

"A" terminal needs 12V at all times. "S" terminal should be 12V switched with the ignition. "F" voltage will only be present with the ignition on.

 

[DirtDonk]

What Viper said.

No it is reading backwards

Then at some point, someone disconnected the big bullet-style connector adjacent to the back of the ammeter, and put them back through the loop in reverse order.
Assuming it's still an actual ammeter, and not a replacement volt-meter instead, you can reach up behind the dash and disconnect it and route it back through the inductive loop in the reverse order that it was before.
If that makes sense...

At the plug I go :
S. 12.6 volts green/ red tracer

Only with the key in the ON position though, correct?

F 0v. Orange wire

Probably because of the next one...

A 0v. Yellow wire

There's your problem, as they used to say.
As Viper said, this is supposed to show full battery voltage at all times.
Since it sounds like all the rest of the accessories have power, then the main fusible link at the starter relay should be good.
Somewhere nearby in the harness (under the tape) is a splice where the Yellow wire is attached to the large Black wire. This is where it senses the battery voltage.
Can you post up a picture of the wiring on and around your starter relay/solenoid on the wheel well, regulator (wherever it is on yours) and the alternator?
If you don't want to become a contributor at this time, you can either use your "garage" or "gallery" functions in the user-CP, or you can e-mail them to me at paulb@wildhorses4x4.com and I will post them up here for everyone to check out.

Paul

 

[Oldtimer]

Here is 73 schematic. Note that the yellow wire goes thru a 3 pin connector (C-206). That may be where there is a bad connection.

This is picture of bullet connector Paul mentioned.
If ammeter reads backwards, the BK-YL stripe wire needs to go thru the green ammeter loop in the other direction.
Easiest way to access back of speedometer, is to pull driver side fresh air box.

 

[Tamnative3]

Here is 73 schematic. Note that the yellow wire goes thru a 3 pin connector (C-206). That may be where there is a bad connection.

View attachment 969147

This is picture of bullet connector Paul mentioned.
If ammeter reads backwards, the BK-YL stripe wire needs to go thru the green ammeter loop in the other direction.
Easiest way to access back of speedometer, is to pull driver side fresh air box.

View attachment 969150

Thanks I never woold have thought of that.

 

[Tamnative3]

Thanks I never woold have thought of that.

Got the ammeter working correctly thanks for the recommendation

 

[Tamnative3]

What Viper said.


Then at some point, someone disconnected the big bullet-style connector adjacent to the back of the ammeter, and put them back through the loop in reverse order.
Assuming it's still an actual ammeter, and not a replacement volt-meter instead, you can reach up behind the dash and disconnect it and route it back through the inductive loop in the reverse order that it was before.
If that makes sense...

Only with the key in the ON position though, correct?

Probably because of the next one...

There's your problem, as they used to say.
As Viper said, this is supposed to show full battery voltage at all times.
Since it sounds like all the rest of the accessories have power, then the main fusible link at the starter relay should be good.
Somewhere nearby in the harness (under the tape) is a splice where the Yellow wire is attached to the large Black wire. This is where it senses the battery voltage.
Can you post up a picture of the wiring on and around your starter relay/solenoid on the wheel well, regulator (wherever it is on yours) and the alternator?
If you don't want to become a contributor at this time, you can either use your "garage" or "gallery" functions in the user-CP, or you can e-mail them to me at paulb@wildhorses4x4.com and I will post them up here for everyone to check out.

Paul

Ok I’m stumped this is the 3rd alt. All checked out good the last one is a different rebuilder and a better quality. Here’s what I have as far as measurements I goofed up on the ones I gave you last.
Battery not hooked up reads 12.26 volts
Battery with engine running 12.14 volts
checked the wiring and I DO have 12.21 volts key on not running
checked the alternator orange battery wire key on not running 12.21 volts
no power to S terminal green wire with key on.
Checked output at the battery while engine running 12.14 volts. To say the least I’m lost.

 

[Tamnative3]

Also I have tried 2 different regulators.

 

[Viperwolf1]

no power to S terminal green wire with key on.

There's your problem, now. That green-red wire comes from the ignition switch but it does go through the C206 connector at the passenger firewall. That connector is in a bad location as it tends to get wet and corrode the terminals there.

 

[Oldtimer]

With key ON, check for 12 volts at R-Y stripe wire for brake warning lamp, or BL wire for emission control solenoid (on or near carb).
They are connected to the GR-R stripe wire that turns on voltage regulator.

 

[Tamnative3]

There's your problem, now. That green-red wire comes from the ignition switch but it does go through the C206 connector at the passenger firewall. That connector is in a bad location as it tends to get wet and corrode the terminals there.

Found the plug and your right no power with key on looked under dash and found it had been broken or cut now I’ll splice it into the wire that goes to the coil as I think that’s where it originated. I’m not looking forward to going back under there and might just remove the seat. Thanks

 

[Tamnative3]

With key ON, check for 12 volts at R-Y stripe wire for brake warning lamp, or BL wire for emission control solenoid (on or near carb).
They are connected to the GR-R stripe wire that turns on voltage regulator.


View attachment 969167

Thanks I think I have it figured out not looking forward to it.

 

[EPB72]

Found the plug and your right no power with key on looked under dash and found it had been broken or cut now I’ll splice it into the wire that goes to the coil as I think that’s where it originated. I’m not looking forward to going back under there and might just remove the seat. Thanks

yes they originate at the same terminal at the ignition switch,, but be carefull if your splicing in on the coil B+ feed wire as that wire shortly after leaving ignition switch has the resistor wire .. SO you would need to spice in before the resistor wire . or replace terminal at Ignition switch connector block as I think Toms has replacements ?.

 

[Oldtimer]

As EPB72 states, the GR-R wire (voltage regulator ON) and the R-GR (coil power) originate at ignition switch.
The R-GR wire is a resistance wire and will not provide a full 12v to turn on voltage regulator.
You need to find the ignition switch end of the cut GR-R wire for your splice.
It may be tied into an aftermarket stereo, amp, aux lights, etc.

When working under dash, I pull drivers seat, and add a folded moving blanket to foot well to make it even with rear floor.

 

[Tamnative3]

yes they originate at the same terminal at the ignition switch,, but be carefull if your splicing in on the coil B+ feed wire as that wire shortly after leaving ignition switch has the resistor wire .. SO you would need to spice in before the resistor wire . or replace terminal at Ignition switch connector block as I think Toms has replacements ?.

I redid the ignition and have no resistor wire

 

[Tamnative3]

I got it working and want to thank all of you for the help before I post another weird electrical problem.

 

[DirtDonk]

So the new splice was the fix?
Power to the "S" terminal of the regulator?

Paul