choke setting
- Thread starter Bobby O
- Start date
miker98038
Well-known member
There should also be some instructions in the shop manual about setting the fast idle screw, etc. It's pretty simple once you've done it.
Daves55Sedan
Well-known member
If it is a 2-bbl Ford EBU or Holley 2100 carburetor, try this:
There is a choke cable mounting bracket with clamp on the rear passenger side. Loosen the slotted screw on the clamp (may need to hold the nut on the backside with a 3/8" wrench).
Now, loosen the screw on the choke actuating lever (where the cable goes thru the round brass clevis.
Next, push the choke control knob on the dashboard all the way in.
Then go back under the hood and push the choke butterfly in the carburator so that it is all the way open.
It may be necessary to pull the choke cable all the way out of the clevis and the clamp to straighten the end of the cable a little bit (but leave a little curve in it at the end). Now thread the cable back through the clamp and into the clevis. You should have a little bit of cable extending out of the brass clevis. Be sure that the choke butterfly is still fully open at this point.
Tighten the screw down at the brass clevis (just snug up good, no need to crush the cable end).
Tighten the cable clamp screw using your screwdriver and 3/8" wrench.
Important: Go push the dashboard choke knob all the back in, then go back and look at the choke butterfly. If the butterfly is not completely open (straight up), your cable housing is pushed thru the clamp too close to the choke actuator clevis.
You will need to loosen the clamp again and push the cable backward thru the clamp to allow more room for the cable end to protrude from the cable housing.
After adjusting, test again, until you have the choke butterfly fully open when the knob is pushed in all the way AND the choke butterfly should fully close when the knob is pulled out.
It's all about how the cable is positioned in the clamp, as well as which point on the cable end is fastened in the clevis.
There is a choke cable mounting bracket with clamp on the rear passenger side. Loosen the slotted screw on the clamp (may need to hold the nut on the backside with a 3/8" wrench).
Now, loosen the screw on the choke actuating lever (where the cable goes thru the round brass clevis.
Next, push the choke control knob on the dashboard all the way in.
Then go back under the hood and push the choke butterfly in the carburator so that it is all the way open.
It may be necessary to pull the choke cable all the way out of the clevis and the clamp to straighten the end of the cable a little bit (but leave a little curve in it at the end). Now thread the cable back through the clamp and into the clevis. You should have a little bit of cable extending out of the brass clevis. Be sure that the choke butterfly is still fully open at this point.
Tighten the screw down at the brass clevis (just snug up good, no need to crush the cable end).
Tighten the cable clamp screw using your screwdriver and 3/8" wrench.
Important: Go push the dashboard choke knob all the back in, then go back and look at the choke butterfly. If the butterfly is not completely open (straight up), your cable housing is pushed thru the clamp too close to the choke actuator clevis.
You will need to loosen the clamp again and push the cable backward thru the clamp to allow more room for the cable end to protrude from the cable housing.
After adjusting, test again, until you have the choke butterfly fully open when the knob is pushed in all the way AND the choke butterfly should fully close when the knob is pulled out.
It's all about how the cable is positioned in the clamp, as well as which point on the cable end is fastened in the clevis.
Daves55Sedan
Well-known member
scicala
Well-known member
There is no fast idle speed adjustment screw on this style carb on '55 Fords. Just one screw for warm idle speed. You take what you get for fast idle when the choke cable is pulled out.
Sal
Daves55Sedan
Well-known member
That's correct! the Early to mid-fifties 2-bbl carbs had a fast-idle cam in the fashion of a bump-out in the choke actuator lever, which pushed the accelerator lever back, translating to movement forward via the lever pivot point. However, the cam allowed for slower fast-idle speeds as the choke knob was pushed in, as you can see in this photo
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miker98038
Well-known member
Thanks, Sal and Dave, you've rung a bell from way back. I'm not sure I ever worked on one of those, but I remember the "manual choke no fast idle setting" from the early days on Dad's marine engines. Not a problem on them, you just didn't pull the throttle lever back till it warmed up.
Daves55Sedan
Well-known member
I don't know what you mean by "manual choke no fast idle setting", unless you mean that it is not adjustable. That is true. But the fast-idle cam on the choke actuator lever, although it is fixed/integral with the lever, you can achieve different idle speeds depending upon how much the choke knob is pulled out. And if you pulled out the choke knob all the way, the engine races in idle.
The choke actuator lever has a dual function independent of the accelerator linkage and idle adjustment. The lever activates the choke butterfly and as the lever pivots, the fast idle cam pushes against the accel lever.
I can't imagine anybody needing to pull the choke lever out all the way unless the temperature is sub-zero.
I once had a '57 Y-block. They all had automatic chokes. Mine would never disengage to fully open, so I ripped it out and installed a cheap manual choke conversion kit. Loved it.
The choke actuator lever has a dual function independent of the accelerator linkage and idle adjustment. The lever activates the choke butterfly and as the lever pivots, the fast idle cam pushes against the accel lever.
I can't imagine anybody needing to pull the choke lever out all the way unless the temperature is sub-zero.
I once had a '57 Y-block. They all had automatic chokes. Mine would never disengage to fully open, so I ripped it out and installed a cheap manual choke conversion kit. Loved it.
Daves55Sedan
Well-known member
Bobby O sent out individual notes of thanx to folks who replied on this article, so it sounds like he got it fixed based upon everyones input.