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Discussion Starter #1
I have an Edelbrock 'Performer' series carburetor (matched with the 'Performer' intake) I'm PRETTY sure that my automatic choke is not working. I THINK it was after the guys finished rebuilding the top half of my engine (heads & valves) that I noticed that it seemed to be racing a lot, even after I thought it was warmed up. So, I took a look at the linkage (of course I have almost NO idea what I am doing) and I noticed that there was a screw, not the idle screw but one kind of below it and pointed more downward so that you have to pull the throttle back almost all the way in order to reach it. It SEEMED like that screw was cranked almost all the way in and it APPEARED that it was holding the throttle open or something that was causing my engine to race, even after it seemed like it was warmed up. It LOOKS like it is supposed to hit that butterfly valve and I guess close off the air on the top of the carburetor, thus drawing more gasoline in. I'm not sure...

So, what I did was I backed off that screw where it didn't seem to hang up the throttle any more. I pulled it quite a ways back out. Well, consequently after my doing that, when I start my car in the morning when cold, there doesn't seem to be ANY kind of choke or anything giving it more gasoline until it warms up. I just idle it at a little higher RPM for a minute or two and then I take off and it seems to do okay after a few minutes running.

Do I then need to crank that screw BACK in some in order for it to do whatever it is supposed to do. It is an electric choke and it seems to be wired in right; I just have NO bloody idea quite how it works. Could that little screw below the idle screw have something to do with it not 'choking' when cold? Seems weird that it would be something 'Mechanical' like that since it is an 'Electric' choke, but the hell if I know... Is it REALLY that vital to have a choke in the morning, or can I just simply idle it at a higher RPM for a couple of minutes? Is it pretty much the same thing?

Thanks!
 
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you again? lol


you can just hold the idle up with the gas pedal if you want/need when it is cold. it won't hurt anything, however you need to make sure the choke butterfly is fully open when it is warmed up.

it sounds like the screw you turned is the idle screw that is operational when the choke is ON.

It rides on a little "cam". when the butterfly is closed the cam is supposed to push on the screw which opens the throttle.

as the butterfly opens the cam rotates to a smaller diameter thereby closing the throttle some.

when the butterfly is completely open the screw should NOT touch the cam. if it does you will not be able to lower your idle by your std idle speed screw if you need.


here's one option.

with the engine cold open the throttle.

the butterfly should be open around 1/8 inch when it is around 50 - 55 degrees.

if it is way off then loosen the 3 small screws on ring that holds it on.

hold throttle open and turn the plastic housing until your choke is properly set.

tighten screws.

start car. as soon as the engine starts it should suck the choke open to around 3/8".

if idle is too low after around 15 seconds then turn the screw in one turn etc.

your choke should turn off in less than 5 minutes. often it is 2 minutes. if it does not then either it is binding or not connected. it should be connected to 12 volts but nit to the coil wire.

i connect them to the wire on the small post pointing a bit forward on the starter solenoid or the neutral safety switch wire behind the engine.
 

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Discussion Starter #3
you again? lol


you can just hold the idle up with the gas pedal if you want/need when it is cold. it won't hurt anything, however you need to make sure the choke butterfly is fully open when it is warmed up.

it sounds like the screw you turned is the idle screw that is operational when the choke is ON.

It rides on a little "cam". when the butterfly is closed the cam is supposed to push on the screw which opens the throttle.

as the butterfly opens the cam rotates to a smaller diameter thereby closing the throttle some.

when the butterfly is completely open the screw should NOT touch the cam. if it does you will not be able to lower your idle by your std idle speed screw if you need.


here's one option.

with the engine cold open the throttle.

the butterfly should be open around 1/8 inch when it is around 50 - 55 degrees.

if it is way off then loosen the 3 small screws on ring that holds it on.

hold throttle open and turn the plastic housing until your choke is properly set.

tighten screws.

start car. as soon as the engine starts it should suck the choke open to around 3/8".

if idle is too low after around 15 seconds then turn the screw in one turn etc.

your choke should turn off in less than 5 minutes. often it is 2 minutes. if it does not then either it is binding or not connected. it should be connected to 12 volts but nit to the coil wire.

i connect them to the wire on the small post pointing a bit forward on the starter solenoid or the neutral safety switch wire behind the engine.
Excellent! I will check that.

Thank you!
 

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Hello Lathe,
Sounds like you are in good shape here and 67 has given you some great advice.

I would like to offer a few thoughts and tips.
1. - If you have an electric choke - why not have it work right, I do not mean
that as a wise crack. Just that for years I ran without a choke and it is OK
but why not use what you have

2. - Not certain if you understand the choke and its setting.

Keep in mind there are actually 2 idle speed screws.
One is for COLD conditions and fast idle - - the other is for normal idle,

Lets see if I can explain a little more. I am almost certain what you did was to
back the fast idle screw off way too much.

So - - when the motor is warm the idle speed is controlled by the "regular" idle screw
on the driver side - -
when the motor is COLD the idle is controlled by the screw on the pass side of the carb the one you moved.

Here is a pretty simple way of getting you back into the ballpark

First - -warm the motor and let her get nice and warm - -now - -turn the idle screw
in the driver side - you want the idle to drop a little - -when you have that
condition - -great

Now turn the "fast idle" screw in untill you just hear a little increase in the rpm. At that point - -stop - - Now turn the FAST IDLE screw counter clockwise - "back it off" one FULL turn. This should get you close and then you can adjust things properly
with a COLD motor.

You need to get the screw close and yet have the regular idle screw set at a low enough idle speed.
My guess is the normal idle was/is set too far in - -motor racing with this screw.

When you backed off the fast idle screw - -I am confident you went tooooo much

I am sure you are close to getting this right. See once you get the WARM idle screw
set - -then with a cold motor - you focus on the FAST idle screw.

Not certain if I have helped or have made you more confused

Print Dad
 

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Discussion Starter #5
Hello Lathe,
Sounds like you are in good shape here and 67 has given you some great advice.

I would like to offer a few thoughts and tips.
1. - If you have an electric choke - why not have it work right, I do not mean
that as a wise crack. Just that for years I ran without a choke and it is OK
but why not use what you have

2. - Not certain if you understand the choke and its setting.

Keep in mind there are actually 2 idle speed screws.
One is for COLD conditions and fast idle - - the other is for normal idle,

Lets see if I can explain a little more. I am almost certain what you did was to
back the fast idle screw off way too much.

So - - when the motor is warm the idle speed is controlled by the "regular" idle screw
on the driver side - -
when the motor is COLD the idle is controlled by the screw on the pass side of the carb the one you moved.

Here is a pretty simple way of getting you back into the ballpark

First - -warm the motor and let her get nice and warm - -now - -turn the idle screw
in the driver side - you want the idle to drop a little - -when you have that
condition - -great

Now turn the "fast idle" screw in untill you just hear a little increase in the rpm. At that point - -stop - - Now turn the FAST IDLE screw counter clockwise - "back it off" one FULL turn. This should get you close and then you can adjust things properly
with a COLD motor.

You need to get the screw close and yet have the regular idle screw set at a low enough idle speed.
My guess is the normal idle was/is set too far in - -motor racing with this screw.

When you backed off the fast idle screw - -I am confident you went tooooo much

I am sure you are close to getting this right. See once you get the WARM idle screw
set - -then with a cold motor - you focus on the FAST idle screw.

Not certain if I have helped or have made you more confused

Print Dad
Yes, I see exactly what you are saying; thank you for the clear explanation of what to do first when it is warm, I think that will be a big help. I'll try this first to get it in the ballpark, as you say, and then when cold I will apply what 67 told me to get the choke set properly.

And YES, you are quite right; when the idle was always racing when it was cold, I DID in fact back out that screw a LOT :) I even figured at the time it was probably too much. Hey, one thing that 67 mentioned that I'm not to clear about, but I'm sure I should do once I get it close while warm, is that rotating and 3 screw thing. I noticed when I was screwing around with the choke (opposite side of the carburetor than the throttle linkage) I was trying to see how the butterfly valve moved and I noticed that there is a round, sort of slightly larger than quarter sized disc that seems to turn the choke. It appeared to be turning freely and I could easily rotate it either direction. Is that right...?! Shouldn't it be tight and NOT able to move so freely? I'm thinking that this may be some further fallout from my mechanic not being familiar with older cars.

Any further clarification would be great.

Thanks to both of you!
 
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hello

if you use print dads method to adjust the screw the butterfly must be fully open.

you can also do this:

with the engine cold, somehow prop your throttle linkage so it is at least 1/2 way open.

your choke should be almost closed if it is around 60 degrees or less. if it is then turn your ignition key to the run position then watch your choke. it should slowly open all the way in less than 5 minutes. if it does not move at all you need to fix it.

the big round black think with the wires attached is your choke adjustment. it should not turn freely unless you loosen the screws.

the second photo is the screw you backed. the half round thing is what i called a cam. it has small steps cut into it. this is what i said rotates as the butterfly moves. if you read my post again it will hopefully all make sense to you now after seeing these photos.

the third photo is the butterfly that i mentioned. it should be close a bit more than this when it is the temp i previously described.
 

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Discussion Starter #7
hello

if you use print dads method to adjust the screw the butterfly must be fully open.

you can also do this:

with the engine cold, somehow prop your throttle linkage so it is at least 1/2 way open.

your choke should be almost closed if it is around 60 degrees or less. if it is then turn your ignition key to the run position then watch your choke. it should slowly open all the way in less than 5 minutes. if it does not move at all you need to fix it.

the big round black think with the wires attached is your choke adjustment. it should not turn freely unless you loosen the screws.

the second photo is the screw you backed. the half round thing is what i called a cam. it has small steps cut into it. this is what i said rotates as the butterfly moves. if you read my post again it will hopefully all make sense to you now after seeing these photos.

the third photo is the butterfly that i mentioned. it should be close a bit more than this when it is the temp i previously described.
Hey Bro!

Appreciate the additional instructions; yeah, I understand what you are saying and I will definitely do that too. That is perfect too, because this way I can bloody TELL if my choke is even working right to start with. For some odd reason, the board here is NOT notifying me when others answer my threads, so sorry about that, I just saw this now.

Sure appreciate the help; between both sets of instructions, even I shouldn't screw that up! :)
 

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I see you live in California, as do I. We don't need a choke out here, doesn't really get cold enough. For a cheap fix for now, just wire it wide open.
 

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I see you live in California, as do I. We don't need a choke out here, doesn't really get cold enough. For a cheap fix for now, just wire it wide open.
Heh heh... Yeah, that's why I haven't really 'sweated' it that much... :)

But, it WOULD be nice to KNOW how to get it working right...

Thanks mate!
 
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