Where can I hook up an electric choke?

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Chained_360

Chained_360

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So I'm trying to find a 12v source tied to the ignition switch that will provide power to my electric choke. I've tried the pink wire that supplies power to the wiper switch, but now my wipers don't work (too pissed off to mess with it more). Where can I find a good, relatively accessible (not that important) wire that I can splice into?

This is for a 1968 Plymouth Barracuda notchback.
 
I think you could use the positive at the coil
 
Yeah the blue wire is the usual spot. It's a "run" feed from the ignition switch.
However, choke heaters pull some juice, and they pull it through the bulkhead connector, through the ammeter,through the switch, back down and out the bulkhead connector and up and over the back of the engine to the ballast resistor.That poor wire gets no respect.Yeah the factory did it that way, but the copper now is nearly 50 years old.That blue wire continues to the VR.
I wouldn't run the choke heater off the coil though, cuz the coil pulls electrons through the ballast resistor. Now the coil and heater would have to share that resistor. It will get good and hot, and start choking them electrons down to a trickle. If I had to hook it to that blue wire somewhere, I would hook it to the ignition side of the ballast resistor.But when you do that, make sure the connection will stay good forever, cuz you are the only guy that knows where it goes, and if that connection fails, the engine will shut down. And almost guaranteed it will happen late at night, and far from home, and it will be flipping cold outside.

What I did was run all the underhood stuff off a relay, triggered by that blue wire. Now all that stuff gets fused, full battery voltage.If you do it this way, don't cheap out on the relay.And protect it from heat and water.
 
In the holley installation manual, it specifically states to not take power off the coil as it will cause numerous engine problems
 
As AJ said, the blue coming out of the bulkhead TO the coil resistor. One thing you could do is to CUT that wire and rig a relay in there. Trigger the relay from the bulkhead end, and hook the engine end to the load side of the relay contacts. Fuse the source for the relay off the start relay, and run "everything" including the choke off that.

There is only one "switched ignition" under the hood in "run" and that is the "normally" dark blue IGN1 or "run" feed.

IT IS NOT fused.
 
Get a three prong oil pressure sending unit from your local NAPA store, run a fused 12v feed off the the battery or at the heavy lug on the starter solenoid to one of the the "normally open" lugs on the sending unit. Run a wire from the other "normally open" lug directly to the choke. Easy, safe, and unlike the other methods, leaving the key on wont open the choke...
 
Awesome, thank you guys so much. I'll head down to the local geek warehouse (awwww yisss... Frigid North) and pick up some stuff.

But just double checking... this blue wire IS in the engine compartment, right? I don't wanna even think about jamming myself underneath that dash again...
 
Chained_360 said:
Awesome, thank you guys so much. I'll head down to the local geek warehouse (awwww yisss... Frigid North) and pick up some stuff.

But just double checking... this blue wire IS in the engine compartment, right? I don't wanna even think about jamming myself underneath that dash again...
Click to expand...

Why even bother with the blue wire at all?
 
Dam Repliracer that is pretty ingenious! If I wasn't going to FI, I would being making that change right now...
 
cudascott said:
I think you could use the positive at the coil
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No, the coil only gets 6 volts, the choke needs 12 volts...


Hook it up to the input side of the ballast resistor with a piggyback terminal.

disconnect both connections to the ballast, then turn the ignition on, then poke each connector with a test light and see which one is hot. Use that one to feed the + for the coil...
 
piggyback.jpg
These work great!
 
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I'd do what replicaracer suggest or run a relay like 67Dart suggest.

I don't like any significant load on the ignition power wires than necessary. A good relay will draw less than .25 amps, so trigger the relay, 85 terminal with a wire from the blue ignition wire. Run a fused power line to the 30 relay terminal and out to choke on 87 terminal. Ground the relay from 86 terminal. As Replicaracer mentions, the choke will be hot with key in run.
 
I have a question about the chokes. Do they shut off when open or do the coils continue to draw current? The relay set up is definitely the way to go.
 
As far as I know the chokes are basically a dead short/resistance situation.
 
crackedback said:
As far as I know the chokes are basically a dead short/resistance situation.
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I've never bothered to find out. I always assumed "the little box" controlled them

In the 73 shop manual, they refer to the choke control module as "time temperature" control, and there's a short test in there evidently should time off at less than 5 min.
 
replicaracer43 said:
Get a three prong oil pressure sending unit from your local NAPA store, run a fused 12v feed off the the battery or at the heavy lug on the starter solenoid to one of the the "normally open" lugs on the sending unit. Run a wire from the other "normally open" lug directly to the choke. Easy, safe, and unlike the other methods, leaving the key on wont open the choke...
Click to expand...
Ok I like the idea of the oil sender connecting the circuit for the electric choke because the engine runs before the choke gets power but doesn't the oil sending unit only have 5 volts going to it normally? Also what year make and model sending unit do you ask for
 
Get it from ballast resistor.
ratvon said:
Ok I like the idea of the oil sender connecting the circuit for the electric choke because the engine runs before the choke gets power but doesn't the oil sending unit only have 5 volts going to it normally? Also what year make and model sending unit do you ask for
Click to expand...
 
ratvon said:
That's where I'm going with pertronix 3
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I really like what that replicarracer43 but my concern is the oil sending unit is 5v (I'm pretty sure) and whats going to happen wben i run a 12v circut through .....anyone have any input on this?
 
Answered again without all the drama!

How sweet it is..... & the search function
 
ratvon said:
I really like what that replicarracer43 but my concern is the oil sending unit is 5v (I'm pretty sure) and whats going to happen wben i run a 12v circut through .....anyone have any input on this?
Click to expand...
The oil pressure sending unit is a pressure switch...it's not a "5 volt" circuit... one lug gets grounded when there is NO oil pressure, that turns on the light... the other 2 terminals are "normally open" and become "closed" when there IS oil pressure....you put 12 volts fused to one side, the other to choke coil...easy peasy
 
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