Proper Choke Setting

[goodnigh]

As I recall from long ago you adjust the electric choke when cold

so there is a 7/64 inch gap in the choke plate. The cold weather is

playing havoc with this car, very difficult to start when cold. If the

choke plate is completely closed, the car won't start. Am I correct?

mike

 

[Don C]

I believe the choke should be completely closed before you try to start it. After it starts the choke pull-off will open it up to about 1/4 inch.

 

[Bill73Ragtop]

Actually I believe you want a small open gap in order for it to start. The choke plate will gradually open as warm up occurs. If fully closed, it will not start.

Back in the day, I can recall dropping a pencil into the carb to open the plate enough to get it started.....and keep the pedal down until it would run on its own.....sheesh! middle of the night, temps in the single digits or low teens trying to start the car in a parking lot.....!

 

[mustang7173]

goodnigh,

Yes, you will need have some opening to allow air in. Check this instruction out.

http://www.autozone.com/autozone/repairguides/Carbureted-Fuel-System/Carburetor-Assembly/_/P-0900c1528027a183

Or this:

* Choke valve pull-off set-up: This sets the initial choke valve opening for cold start. We'll use a drill bit to measure the distance between the lower choke valve edge and the air horn wall.

- Loosen the three screws and turn the bimetallic choke spring 90 degrees rich (spring tighter)

- Open the throttle valves and then release them to set the fast idle cam and the choke valve closed.

- On the choke pull-off diaphragm, push the actuator towards the diaphragm housing until it is fully seated and hold it there.

- Using a 7/64" drill bit, measure the distance between the lower edge of the large choke valve and the air horn wall.

- Adjust the recessed screw on the back of the choke pull-off diaphragm with a 1/4" nutdriver until opening is 7/64"

- Release the choke pull-off actuator but, leave the bimetallic spring 90 degrees rich for now.

* Fast Idle Cam Linkage: This adjustment is very similar to the one above.

- Open the throttle valves and then release them to ensure the fast idle cam is set and the choke closed.

- Just like above, push the choke pull-off actuator until it is fully seated and then hold it there.

- Open the throttle valves and release allowing the fast idle cam to drop.

- The fast idle screw-end should be resting on the "V" mark on the fast idle cam.

- The adjustment screw is located on the upper choke linkage arm with the screw head facing upward. Use a 1/4" nutdriver to turn the screw.

- Repeat the above procedure until the fast idle screw rests on the "V" mark.

mustang7173

 

[TommyK]

Actually I believe you want a small open gap in order for it to start. The choke plate will gradually open as warm up occurs. If fully closed, it will not start.

Back in the day, I can recall dropping a pencil into the carb to open the plate enough to get it started.....and keep the pedal down until it would run on its own.....sheesh! middle of the night, temps in the single digits or low teens trying to start the car in a parking lot.....!

Bill,

With all due respect I do not believe that is correct. I agree with Don C. If the choke butterfly is already open any amount before the engine starts what is the purpose of a pull off?

I don't know how to post a pdf or I would attach the Holley document illustrating the pull off adjustment procedure. I am sure it is on their website.