Electric Choke and Wiring

[torbsim]

Hello everyone, the cable for the choke (black and white) on the engine wiring harness of my 1973 351C V2, can I use this for the electric choke, or should I use a direct cable from the alternator to the electric choke and if so, what is the black and white choke cable actually for?




Thank you!
Ben

 

[Ron Tanzi]

I used the throttle solenoid power feed wire on my 72 2V. I removed the solenoid when I changed to a Holley. It supplies 12 volts with the key on. I think most people use that as their choke power supply.

Ron

 

[Doug's 73 Mach1]

The white black factory choke wire is connected to the white black wire to the alternator. No need to run another wire unless your wire harness(es) are damaged, modified or suspect. You could check continuity from the alternator back white wire to the choke black white wire, there should be continuity.

 

[torbsim]

Ok, there is still no new wiring harness on my alternator, as the delivery has been delayed from week to week for over 4 weeks now. I'm already thinking about installing a 70 AMP alternator as this wiring harness is still available, and the other one has apparently been sold out for months.

I didn't realize that the cable practically runs around the engine block once and then ends up back at the choke. I will make sure that I do everything on the car like the factory, and then use the black and white cable for the choke. I have practically "killed" the cables for the solenoids, as I have also removed these. They no longer make any sense and also provide less power.

Thanks for the tips. You are the best!
Ben

 

[Doug's 73 Mach1]

70 amp alternators are correct for 73 Mach 1s that have factory rear defrost. I believe 55 or 61 amp without the rear defrost. Connections to the 70 amp alternator are different than for the lower amp alternators. 73 was the only year to use the 70 amp alt. This was do to the 73 rear defrost being higher wattage (higher amp draw) than 71/72s. 73s used a dedicated rear defrost 12 volt feed (yellow with integral fusible link) connected to the junction block forward of the starter solenoid if the car was equipped with factory amp meter according to the 73 Mustang wiring diagram. To the starter solenoid battery post without amp meter. 71/72s used a black yellow hash feed wire connected to a circuit breaker at the solenoid, that feed wire also used for to feed the convenience group, power windows or convertible top. 73s also used a black yellow dash feed wire for the convenience group, PW or convertible top only, not for the rear defrost feed.

 

[torbsim]

70 amp alternators are correct for 73 Mach 1s that have factory rear defrost. I believe 55 or 61 amp without the rear defrost. Connections to the 70 amp alternator are different than for the lower amp alternators. 73 was the only year to use the 70 amp alt. This was do to the 73 rear defrost being higher wattage (higher amp draw) than 71/72s. 73s used a dedicated rear defrost 12 volt feed (yellow with integral fusible link) connected to the junction block forward of the starter solenoid if the car was equipped with factory amp meter according to the 73 Mustang wiring diagram. To the starter solenoid battery post without amp meter. 71/72s used a black yellow hash feed wire connected to a circuit breaker at the solenoid, that feed wire also used for to feed the convenience group, power windows or convertible top. 73s also used a black yellow dash feed wire for the convenience group, PW or convertible top only, not for the rear defrost feed.

Good to know, then I will also restore this factory state and not work with the 55 amp alternator. The yellow cable for the defroster is next to the black cable as you described. It is currently not connected and has been literally "shredded". I have to repair that first. I can't say what else the previous owner left wrong or incorrect. I have spent hours reading through documents and manuals but I am not a mechanic and do this as a hobby. Thanks for your great help, thanks Doug!

 

[torbsim]

70 amp alternators are correct for 73 Mach 1s that have factory rear defrost. I believe 55 or 61 amp without the rear defrost. Connections to the 70 amp alternator are different than for the lower amp alternators. 73 was the only year to use the 70 amp alt. This was do to the 73 rear defrost being higher wattage (higher amp draw) than 71/72s. 73s used a dedicated rear defrost 12 volt feed (yellow with integral fusible link) connected to the junction block forward of the starter solenoid if the car was equipped with factory amp meter according to the 73 Mustang wiring diagram. To the starter solenoid battery post without amp meter. 71/72s used a black yellow hash feed wire connected to a circuit breaker at the solenoid, that feed wire also used for to feed the convenience group, power windows or convertible top. 73s also used a black yellow dash feed wire for the convenience group, PW or convertible top only, not for the rear defrost feed.

PS: is the integral fusible link is still available because at my yellow cable is nothing any more, as i said, shredded.

 

[Hemikiller]

You'll have to get a repair end for the fusible link. Some yellow shrink tubing will hide it from the casual observer.

https://www.rockauto.com/en/tools/electrical,fuse,fusible+link,1000927

 

[torbsim]

Thanks guys, as for the repair, I need more than a fuse for the terminal block, just to know what exactly I need to buy. I understand the defroster cable has a 19a fuse, what about the other cables?

 

[torbsim]

The thick yellow wire with the fusible link 14a is #37 on the diagram and goes over the engine along with the black and yellow wire for the power windows etc, attached to the stabilizers for the dome struts. the other yellow wire 37 is part of the main harness and goes under the fan and then attaches to the terminal block. did i summarize this correctly so far, not that i'm mixing up the wires. bzzzzz--boom

 

[tocruise]

The thick yellow wire with the fusible link 14a is #37 on the diagram and goes over the engine along with the black and yellow wire for the power windows etc, attached to the stabilizers for the dome struts. the other yellow wire 37 is part of the main harness and goes under the fan and then attaches to the terminal block. did i summarize this correctly so far, not that i'm mixing up the wires. bzzzzz--boom

Man, I'm trying to figure out the same thing and the harness in my 'stang is a disaster lol.

What wiring diagram/page are you using there? I bought the color diagram from Forel, but it's nowhere near as clear as that!

 

[torbsim]

You'll have to get a repair end for the fusible link. Some yellow shrink tubing will hide it from the casual observer.

https://www.rockauto.com/en/tools/electrical,fuse,fusible+link,1000927

The fusible link is ordered and will be delivered in the middle of july to germany.

 

[Steve McMahan]

That looks like the work of @Fast71. He is the Yoda of wiring diagrams.