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7/04/2022 9:00 PM  #1


Electric Choke

I wired up my choke some time ago and just found out that when I turn the heater on, the current to the choke is gone and the engine is stuck on high idle. When I turn the heater off, the current is back at the choke. I used a test light to realise what was going on.
So it appears that I wired into something I should not have. Strange...
Where do you guys get power from to activate the electric choke?


1964-1/2 D Code Coupe - 289 V8, 4 Speed Toploader, 3.00 ratio rear, Autolite 4100 Carb, 15" tires, Pertronix ignition
 

7/04/2022 9:02 PM  #2


Re: Electric Choke

I wired mine to the ignition switch.


"anyone that stops learning is old, whether at twenty or eighty"Henry Ford
 

7/04/2022 9:19 PM  #3


Re: Electric Choke

Ignition switch ACC post


Money you enjoy wasting is NOT wasted money... unless your wife finds out.
 

7/05/2022 1:09 AM  #4


Re: Electric Choke

Thanks for the comments.
Are you able to advise which wire it is? I chose a positive wire along the firewall in the engine bay. No idea what wire that was, but I have a feeling it feeds the blower motor.
Is there another wire in the engine bay that I can tap into?
Electrics is not my strong suit.


1964-1/2 D Code Coupe - 289 V8, 4 Speed Toploader, 3.00 ratio rear, Autolite 4100 Carb, 15" tires, Pertronix ignition
     Thread Starter
 

7/05/2022 6:44 AM  #5


Re: Electric Choke

There is a threaded stud on the center of the ignition switch on 65/66.  That is accessory connection. 
It is hot in RUN and ACC position of key switch, but is off when in START position.  That works best for an electric choke because, if you have to crank a while to get it started, the choke is not being opened while doing so. Then, once the engine runs, the choke can start to open.


Money you enjoy wasting is NOT wasted money... unless your wife finds out.
 

7/05/2022 9:30 AM  #6


Re: Electric Choke

I only wanted my choke to start opening if the engine is actually running (like a hot air choke would work).  So I used the stator wire from the alternator to trigger a relay that feeds 12v to the choke.  This works great for me.


1968 T-code Coupe with a 302.  Nice car, no show stopper for sure, but I like it.
 

7/05/2022 4:21 PM  #7


Re: Electric Choke

MS wrote:

There is a threaded stud on the center of the ignition switch on 65/66.  That is accessory connection. 
It is hot in RUN and ACC position of key switch, but is off when in START position.  That works best for an electric choke because, if you have to crank a while to get it started, the choke is not being opened while doing so. Then, once the engine runs, the choke can start to open.

Would there be another power source inside the engine bay that I could connect to, or is the ignition switch the best option?


1964-1/2 D Code Coupe - 289 V8, 4 Speed Toploader, 3.00 ratio rear, Autolite 4100 Carb, 15" tires, Pertronix ignition
     Thread Starter
 

7/05/2022 4:22 PM  #8


Re: Electric Choke

Rufus68 wrote:

I only wanted my choke to start opening if the engine is actually running (like a hot air choke would work).  So I used the stator wire from the alternator to trigger a relay that feeds 12v to the choke.  This works great for me.

With connecting to the alternator, is the stator wire the one that feeds to the battery?
If I did that, I would not plan to use a relay. Would this be an issue?


1964-1/2 D Code Coupe - 289 V8, 4 Speed Toploader, 3.00 ratio rear, Autolite 4100 Carb, 15" tires, Pertronix ignition
     Thread Starter
 

7/05/2022 7:01 PM  #9


Re: Electric Choke

I wired mine to the ignition switch that turned out to be a mistake. That has the wire with the resister in it and the choke was taking for ever to open up fully


70, ragtop 351W/416 stroker Edel Performer heads w pro flow 4, Comp roller 35-421-8. T5
 

7/05/2022 8:50 PM  #10


Re: Electric Choke

HudginJ3 wrote:

I wired mine to the ignition switch that turned out to be a mistake. That has the wire with the resister in it and the choke was taking for ever to open up fully

Need the accessory terminal, not the RuN terminal

Only downside is if you like to run the radio with the engine off…

I guess you can hook it to any 12 volt source you want…. Key word 12 volts


Money you enjoy wasting is NOT wasted money... unless your wife finds out.
 

7/05/2022 11:18 PM  #11


Re: Electric Choke

I've seen people discussing how they connected to the alternator for a power source. Apparently Ford did it this way in the factory?
Anyway, here is a photo of my alternator.  Is it the white wire that I connect to? I plan to use a piggyback terminal.




1964-1/2 D Code Coupe - 289 V8, 4 Speed Toploader, 3.00 ratio rear, Autolite 4100 Carb, 15" tires, Pertronix ignition
     Thread Starter
 

7/05/2022 11:53 PM  #12


Re: Electric Choke

The stator output is different from the full voltage output of the alternator that feeds the battery.  The voltage of the stator is less than 12 volts.  That is why I use it to trigger a relay that then sends the full 12 volts to the choke.  The factory chokes that connected directly to the stator must have been made for the lower voltage.  Keep this in mind if your choke calls for 12 volts.
I don't recognize the back of your alternator.  On a Ford 1G alternator the stator output would be labeled "STA" or "S".  On a Ford 3G alternator it is usually a white wire which is the middle wire of the 3 wire connector.




 


1968 T-code Coupe with a 302.  Nice car, no show stopper for sure, but I like it.
 

7/06/2022 12:58 AM  #13


Re: Electric Choke

Rufus68 wrote:

The stator output is different from the full voltage output of the alternator that feeds the battery.  The voltage of the stator is less than 12 volts.  That is why I use it to trigger a relay that then sends the full 12 volts to the choke.  The factory chokes that connected directly to the stator must have been made for the lower voltage.  Keep this in mind if your choke calls for 12 volts.
I don't recognize the back of your alternator.  On a Ford 1G alternator the stator output would be labeled "STA" or "S".  On a Ford 3G alternator it is usually a white wire which is the middle wire of the 3 wire connector.




 

 Thanks for that info. So with the 12volt issue, is the oil pressure sender an option?


1964-1/2 D Code Coupe - 289 V8, 4 Speed Toploader, 3.00 ratio rear, Autolite 4100 Carb, 15" tires, Pertronix ignition
     Thread Starter
 

7/06/2022 7:29 AM  #14


Re: Electric Choke

The oil pressure sender is a grounding wire, not power. You cannot use it to power the choke.  Same for temperature sender.


Money you enjoy wasting is NOT wasted money... unless your wife finds out.
 

7/07/2022 2:17 PM  #15


Re: Electric Choke

MS wrote:

The oil pressure sender is a grounding wire, not power. You cannot use it to power the choke. Same for temperature sender.

Plus the fuel gauge, and there are all powered by the CVU, which is an approximate 5v source.
 


65 Fastback, 351W, 5-speed, 4 wheel discs, 9" rear,  R&C Front End.
 

7/08/2022 12:38 AM  #16


Re: Electric Choke

Rufus68 wrote:

The stator output is different from the full voltage output of the alternator that feeds the battery.  The voltage of the stator is less than 12 volts.  That is why I use it to trigger a relay that then sends the full 12 volts to the choke.  The factory chokes that connected directly to the stator must have been made for the lower voltage.  Keep this in mind if your choke calls for 12 volts.
I don't recognize the back of your alternator.  On a Ford 1G alternator the stator output would be labeled "STA" or "S".  On a Ford 3G alternator it is usually a white wire which is the middle wire of the 3 wire connector.





 

I wired mine to the Stator stud on the alternator, and I've never had any hard starting issues in cold weather (Seattle area).

 


68 coupe - 351W, 4R70W, 9" 3.25 -- 65 convertible - 289 4v, C4, 8" 3.00
 

7/08/2022 4:05 AM  #17


Re: Electric Choke

There are different voltage electric chokes available. The chokes available from Ford from the factory in 73 and after were designed to operate on a little less than 7 volts, and connected directly to the Stator terminal. The Stator DOES NOT give you DC voltage, it’s a rather nasty saw-tooth wave, but perfectly acceptable for a 6 volt choke that is just a heater. If you have a 4300A carb (like what as was used in 74 on a Torino 460 for instance), you can use a 6v electric choke and power it directly from the Stator post: Standard Motor Products CV98
On the other hand, if you have one of the newer 12v chokes from Holley, you will need to connect the Stator to a relay to operate the choke. Use a Potter & Brumfield 1432873-1 relay. It has a 6v coil and 40 amp contacts. Connect the Stator to relay terminal #85, then #86 to chassis (the sheet metal), the battery positive to #30 and the choke to 87. Make sure the other end of the choke is connected to chassis (this is probably already done through the mounting).
This works with the saw-tooth wave coming out of the Stator and the relay doesn’t chatter, because the release voltage of the relay is 0.6v, which is much less than the minimum voltage of 3.36 coming from the stator. Since the Mean (or average) voltage of the Stator is 6.8, the relay is happy and operates normally.

 

7/08/2022 5:40 AM  #18


Re: Electric Choke

Why don't more people use manual chokes?  They are so much easier to install and operate. I've used manual chokes on all of my cars with the exception of my current car, and the only reason I used an electric choke this time is because the carb came with it, so I used it. I expected to remove it and switch it to a manual choke, but so far the electric choke seems to be working well so it can stay for the time being.

 

7/08/2022 8:31 AM  #19


Re: Electric Choke

Chaplin wrote:

Why don't more people use manual chokes? They are so much easier to install and operate. I've used manual chokes on all of my cars with the exception of my current car, and the only reason I used an electric choke this time is because the carb came with it, so I used it. I expected to remove it and switch it to a manual choke, but so far the electric choke seems to be working well so it can stay for the time being.

Well, from my personal experience with manual chokes from many years ago, I would often forget to open it up after the engine warmed up.  Plus, setting it just right to coordinate with the outside temperature could be tricky.

 


65 Fastback, 351W, 5-speed, 4 wheel discs, 9" rear,  R&C Front End.
 

7/08/2022 12:34 PM  #20


Re: Electric Choke

Why use automatic choke?

BECAUSE IT IS AUTOMATIC.


Money you enjoy wasting is NOT wasted money... unless your wife finds out.
 

7/08/2022 12:47 PM  #21


Re: Electric Choke

By that logic we'd all be driving automatics instead of manual transmissions because...they're automatic!   

Kidding aside, I've always preferred a manual choke because I found it gave me the ability to better match the choke to the environmental conditions. And it doesn't much effort to get it work it, just a little tug on the knob and you're all set.  😀

I can't help you if you forget to turn it off though. 😉

Last edited by Chaplin (7/08/2022 12:50 PM)

 

7/08/2022 3:41 PM  #22


Re: Electric Choke

I liked the electrics...back when I ran dripping pots...because as MS says, they are automatic.  Which means less chance of over choking, forgetting to unchoke, and all the extreme wear such things cause to an otherwise perfect engine.  That's one of the primary reasons EFI engines go 200K or more.  No cylinder washing.


"you get what you pay for, good work isn't cheap, and there are NO free lunches...PERIOD!"
 

7/09/2022 5:12 PM  #23


Re: Electric Choke

I ended up getting one of those auto electric guys come out and help me with this problem and he simply wired the choke to the coil.
Before he did that, I mentioned about various forums saying not to do this and he said that is only a concern when you have the old points and balast resistor set up.
I trusted what he said and went along with it.
After it was all set up, he tested the voltage and it had 12 volts. The choke opens up fine too.
Hopefully all is OK 👍


1964-1/2 D Code Coupe - 289 V8, 4 Speed Toploader, 3.00 ratio rear, Autolite 4100 Carb, 15" tires, Pertronix ignition
     Thread Starter
 

7/09/2022 7:14 PM  #24


Re: Electric Choke

I did not wire my choke to the coil.  That pretty well covers my opinion of what you let that guy do to your ignition.  There are just better ways to route power to the choke than risking the power feeding the coil.  Of course I know my opinion only matters to my car.


1968 T-code Coupe with a 302.  Nice car, no show stopper for sure, but I like it.
 

7/10/2022 2:55 PM  #25


Re: Electric Choke

I guess 12 bolts from coil works but it is generally accepted that is NOT the way to do it.

I think you just verified my thoughts about paying someone to work on your car. They invariably take the shortest, easiest route to get something done, not necessarily the best way for it to be done.

Of course, there are professionals out there that will do it right, but it seems they are getting more and more scarce, and most people don’t want to pay the cost to do it right.


Money you enjoy wasting is NOT wasted money... unless your wife finds out.
 

Board footera


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