What the heck is this thing

[electroapprentice]

Wow, you have a mess with that wiring.
The Kwik wire harness has a special wire just for the Regulator/Alternator power. It is the #14 White wire and is labeled Alternator Exciter. Connect it to the Ig terminal on the regulator. Also note that this wire is NOT fused!
Please note: If you are using an alternator with an internal regulator the #14 White will connect to the alternator.

Question for you though, will connecting this to the regulator complete the circuit and allow the battery to charge in the event that I have absolutely everything else connected correctly?

 

[electroapprentice]

does anyone know which bulb in the rear acts as the reverse light on these 68’ 40 series? The turn signal has its own dimmer bulb in the housing and the tail and brake lights are a combo bulb.. but no reverse bulb so it has to be one of them (or not) im just not sure which to use.

 

[Coolerman]

See the attached drawing showing exactly how to wire the alternator to the regulator. This drawing is for 1970 but is the same as the 1968.
WB = White/Black, WR = White/Red, WG = White/Green

The 1968 FJ40 has a separate reverse light. It is not part of the tail light combo bulb. It is mounted in the tub just above the drivers side tail light.
In the rear chassis harness it is the Red/Blue wire that carries the reverse light signal. The circuit is this: key switched+12V goes to one side of the reverse light switch, the other side of the switch goes to the reverse light and the reverse light is grounded.

 

[Coolerman]

Forgot to answer the other question.
Yes if everything is connected as shown, and all the following conditions are met:
1. You have a 10ga or better wire going from the Alternator B+ stud to the battey + terminal
2. The battery is grounded to the frame AND the engine block, and the body, and the battery is good with a good charge
3. The alternator is good, and well grounded to the engine block
4. The regulator is the correct one, works and is properly grounded to the body, then the alternator should charge.

 

[electroapprentice]

Forgot to answer the other question.
Yes if everything is connected as shown, and all the following conditions are met:
1. You have a 10ga or better wire going from the Alternator B+ stud to the battey + terminal
2. The battery is grounded to the frame AND the engine block, and the body, and the battery is good with a good charge
3. The alternator is good, and well grounded to the engine block
4. The regulator is the correct one, works and is properly grounded to the body, then the alternator should charge.

Awesome, thanks again you’re a huge help.

 

[mbplace]

Wow, you have a mess with that wiring.
The Kwik wire harness has a special wire just for the Regulator/Alternator power. It is the #14 White wire and is labeled Alternator Exciter. Connect it to the Ig terminal on the regulator. Also note that this wire is NOT fused!
Please note: If you are using an alternator with an internal regulator the #14 White will connect to the alternator.

Cooolerman -- question here, PO used the kwik wire harness but i think they ran the white wire directly to the alternator rather than thru the regulator (i can't locate a regulator anywhere). where in the harness does that connect? having trouble tracing the wire back.

Having some issues with power supply idling vs cruising and i think its having to do with my wiring setup

 

[Coolerman]

Well... If the alternator currently installed is an internally regulated alternator then the White #14 wire would go straight to the alternator as the excite wire.

What is "power supply idling"? If you mean the truck does not want to idle, the first place to check is to make sure the carb idle solenoid is hooked up to a key switched hot wire. If that carb solenoid is not connected, the truck will not idle. Look at the carb and see if you spot a single (usually black) wire coming out of the base of the carb with a male bullet connector on it. That is what nedds to connect to a key switched hot wire.

 

[mbplace]

Well... If the alternator currently installed is an internally regulated alternator then the White #14 wire would go straight to the alternator as the excite wire.

What is "power supply idling"? If you mean the truck does not want to idle, the first place to check is to make sure the carb idle solenoid is hooked up to a key switched hot wire. If that carb solenoid is not connected, the truck will not idle. Look at the carb and see if you spot a single (usually black) wire coming out of the base of the carb with a male bullet connector on it. That is what nedds to connect to a key switched hot wire.

sorry -- power supply while idling. notice a significant drop in headlight brightness. also when running wipers/heater fan i can tell that the speed fluctuates.

right now the alternator i have in seems to not be internally regulated and only has 1 cable coming out of it and the writing reads "alternator exciter" but having trouble tracing that back to its source.