Electric Choke

[milit73]

I bought a new carb with Electric choke which I have not had before. I thought that you tied this in at the coil but it says not to do that and I new a keyed power source. Where have you guys tied this in?

Also is there an easy way to setup the Idle mixture? I should just read the paperwork that came with it I guess but mainly do I need a vaccum guage to do that or any special tools? what I did read was a little confusing as it was telling me to not let the RPM's go more than 20 or 40 higher as you are adjusting the screws but at this time i have no Tach.

Sorry forgot to tell you what I have. Eldebrock 650 thunder series 383/727 68 superbee

 

[Propwash]

I tied mine in at a power wire to the windshield wiper motor with a splice connection.. As far as the idle/mix screws I believe I remember them stating turn them all the way in, then two full turns out then go from there, from my last rebuild. A vacuum test would be a great way to dial them in.

 

[Sixer]

The choke can have a fairly high draw, and is on from the moment you start the engine until you shut down. So I use a relay, fed directly from the battery, triggered by the ignition feed to the ballast resistor-very little draw from the ignition wiring. This way I don't tax any of the older wiring in Arty. Overkill, maybe-but relays are the best way to go when feeding power hungry devices.

 

[Meep-Meep]

I have mine hooked to the supply side of the ballast but a relay is a great idea.

1.5-2 turns out from lightly seated is a good start for mixture screws. The idle stop screw should be about 1.5 turns in from the throttle being lightly seated in the bores. The goal here is to have the transfer slot about half way uncovered. With the engine warm and everything set properly you adjust the mixture for the lean best idle. Slowly turn one at a time in about 1/4 turn increments and wait a few seconds for the engine to stabilize, then do it again. Too lean and it will missfire but too rich you won't detect much change so it's best to go lean first then back out. You should find the threshold where the engine starts to run well.

 

[milit73]

Hey Meep when you say the supply side of the ballast would that be the supply to the coil or the power supply coming to the ballast? yep dumb question for the day............Thanks

 

[nothingbutdarts]

A factory Chrysler electric choke has a thermistor (turns off power to the choke when the underhood temp. gets up high enough and a "resistor" wired into the syst. What I suggest you do is to check with the carb. manufacturer to see if it's supposed to be wired to 12volts or if it's supposed to be run thru a resistor of some sort!

 

[terzmo]

I always connect the choke to the relay side of ballast resistor...mixture....old fashioned way...when it idles nice...(turn base screws in slowly til idle slows,then back off 2.5 turns

 

[Sixer]

Edelbrock sez 12 volts.

 

[terzmo]

and what's so bad about the 12 volts coming off the starter relay that connects to the side of the resistor???the connecting wire doesn't drop anything...

 

[milit73]

ok so I am a little confused sorry..............do I connect to the side of the resistor thst goes to the coil or the side from the power feed?

 

[terzmo]

power side....it's the "gozzinta" end of the resister...the the side that goes to the coil is the "gozotta"..

 

[62MAX]

Find a choke cut off switch fron any mid 70's Mopar,wire it to the ignition side of the ballast resistor.When engine reaches predetermined temp, power to the choke is cut off.View attachment 88415

 

[Hemi Rebel]

Find a choke cut off switch fron any mid 70's Mopar,wire it to the ignition side of the ballast resistor.When engine reaches predetermined temp, power to the choke is cut off.View attachment 88415

What is said here. I just hooked it up last night on my 87 pickup. I swapped in a 360 from an 86 ramcharger. It had the same wiring seen in this picture. Power came via a three pronged oil pressure switch. The switch closes when oil pressure is sensed, thus only allowing choke operation when the engine is running. It doesnt really have to be a three prong switch. A 2 prong switch that closes when a certain pressure is achieved would work.

 

[tpodwdog]

you want 12 volts to the electric choke.....tap from the ballast youll be fine...OR run a dedicated line from the fuse box on a "KEY ON" aux fuse. or tap into anything thats hot when the key is on.

tapping off the (+) side of the coil when the car is running will give you less than 12 volts due to the ballast resistor cutting voltage to the coil when key is in the "run" position. the only time you have 12 volts to the coil is when youre starting the car and the key is in the "start" position.

 

[Hemi Rebel]

you want 12 volts to the electric choke.....tap from the ballast youll be fine...OR run a dedicated line from the fuse box on a "KEY ON" aux fuse. or tap into anything thats hot when the key is on.

tapping off the (+) side of the coil when the car is running will give you less than 12 volts due to the ballast resistor cutting voltage to the coil when key is in the "run" position. the only time you have 12 volts to the coil is when youre starting the car and the key is in the "start" position.

Problem there is, say you have the key on with the engine off. Listening to the radio, or what have you. The choke is powered up with the engine off. If you run the power feed through an oil pressure switch, it will only get power with the key in the run position, and the engine running.

 

[tpodwdog]

Problem there is, say you have the key on with the engine off. Listening to the radio, or what have you. The choke is powered up with the engine off. If you run the power feed through an oil pressure switch, it will only get power with the key in the run position, and the engine running.

if youre listening to the radio....and the car engine not running, you turn the key to "ACC"....which is accessory. there is no power running to the ballast in this position.

maybe i should have elaborated and not said "aux". you just have to get your friend " the test light". and find the right one on the fuse box that does what you want it to do.

 

[72RoadrunnerGTX]

Aftermarket electric chokes are designed to have full 12 volts for the duration of the run cycle. It’s all about choke timing, any voltage less prolongs the application of the choke. The current draw for most aftermarket choke heaters is around 500 milliamps, .5 amps, and would not require the addition of a relay for the ign circuits of most vehicles. Connecting this additional current load to the coil side of the ballast not only provides a lower voltage to the heater, it may cause coil performance issues. Removing or reducing the 12 volt feed to heater during the run cycle, adding later Chrysler choke controls or resisters; will/can cause the choke to partially close while the engine is warm as the aftermarket choke heater is the only source of heat to the choke spring. That said, choke timing can be intentionally slowed down by adding a small amount resistance, but should never be cut off entirely as some later factory choke controls do.

The later factory (’73 and up)divorced choke assist heating system is very different from an aftermarket electric choke system. Designed to supplement the manifold crossover heat at the divorced choke well in order to speed up the amount of time it takes to open the choke, emissions driven. The heating elements for this system draw closer to 1.7-2.0 amps at full voltage and can create problems for the original ign. circuits. For this reason a choke control was used to stop or reduce the current to the assist heater element after the first 5-10 of operation, much quicker on a warm motor, crossover heat would be sufficient to keep the choke spring relaxed. The control pictured above is the first design, electro mechanical, nothing sold state and very problematic from the start. The internal contacts would burn to the point of in-operation in short order leading to prolonged choke function, poor fuel consumption. They were considered a tune-up item basically back in the day, needing to be replaced at every tune-up. The design was changed later in the seventies to a true sold state, or thermistor based design. Chrysler did use an oil pressure cutoff switch in later years on some models back then for the same reasons listed above, preventing choke spring heating when ign was on for length any time prior to cold start.

Some more info here on modified divorced choke assist heating used for cold intakes

 

[milit73]

Thanks guys I have been having trouble with the cold starts as it will start fine and then start running rough so then I will have to give it some gas to keep it running but it stumbs quite a bit but then will run fine. I will check fro proper voltage.

Other that that I am still dealing with a stumble or basically a "cut out" if I stomp on the gas and not just from a stop. I am challenged when it come to getting a carb dialed in so a shop may have to get it right (hate that but I need to get it right).

 

[Meep-Meep]

If it fires right up then runs really rough soon after you may have a choke pull off problem. The choke adjustments consist of the spring tension (rotating the black plastic housing), the fast idle step cam, the choke blade position relative to the rest of the linkage and the choke pull off. Everything must work together and it will take days to get it right. Basically you have one shot to test an adjustment and that's the first thing in the morning.

 

[72RoadrunnerGTX]

I would highly recommend sorting out the warm running drivability issues before attempting to alter any of the default choke adjustments.