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Discussion Starter #1
Hello all
Recently put Edelbrock 650cfm AVS2 thunder series carb on, lot's of projects were being done on the car & hadn't started it in quite awhile. Now when I try & start her the engine is running crazy fast, like the gas pedal is stomped to the floor fast, way to fast for cold engine, afraid it will tear something up. I've adjusted screw on fast idle cam, adjusted choke back some, tried unplugging vacuum advance, I don't believe in have any massive vacuum leaks. I've even thought for some Reas maybe the ignition advance timing might be off & have tweaked the distributor slightly with no difference....I'm learning as I go with this car, I'm not a mechanical expert by any means. Any thoughts? I just want to get it to idle safely
 

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Look down inside the carb and see if the throttle blades are completely closed. Make sure the accelerator spring is pulling the throttle closed, not open, and back off the HOT idle screw on the driver side if needed until they are, and when the choke is engaged the top butterfly should be just barely open but if you pull it open with your finger to look inside the throttle plates should be just barely open (not quite level) as well.
 
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Had this happen when the accelerator pedal rod was not allowing the carb to close all the way. You can disconnect the accelerator pedal rod and see if still runs really high.
 

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First thought is throttle linkage, so ditto on Vintage Ford Guy.
The way it's supposed to work:
Press the gas pedal, choke closes.
Turn the key, engine starts, choke opens 1/8".
If you have an electric choke, while the engine warms you hit the gas and the choke opens and idle slows until 190 degrees when the choke should be wide open.
If it's starting way too fast then it's a throttle issue rather than a choke issue. The bracket for the throttle cable might need adjusting. Move it forward to allow it to decelerate.
IMG_20150103_225319590.jpg
 
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You should have a hot idle speed screw and a cold idle screw that works on the choke cam. Make sure the screw on the choke cam isn't touching the cam and back the hot idle screw off until it isn't touching the stop tab. That and disconnection the throttle linkage should get it to run or at least try to run. You'll probably have to set initial idle with the hot idle screw.
 

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The DVD I got with my Summit carb says:

Open to full throttle by hand.

While holding the throttle open feel under and just aft of the choke housing.

You should feel a screw. Thats the fast idle adjustment. CW to increase, CCW to decrease. It takes a 1/4 wrench.

Is your Edel similar?
 

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Discussion Starter #8
The DVD I got with my Summit carb says:

Open to full throttle by hand.

While holding the throttle open feel under and just aft of the choke housing.

You should feel a screw. Thats the fast idle adjustment. CW to increase, CCW to decrease. It takes a 1/4 wrench.

Is your Edel similar?
  1. No I don't remember that in my DVD instructions, mine is a Edelbrock AVS2 Thunder series 650cfm....I believe my fast idle is screw is under the fast idle cam, I'll take some pictures when I get home, I'm positive I have it set up incorrect
 

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Discussion Starter #12
I have a clip, was movi
Well to start you should have a clip on that throttle rod.
Well to start you should have a clip on that throttle rod.
Yes I know, car is not being driven yet, still in garage trying to get all this carb stuff figured out, clip not on there as I was disconnecting rod.. actually going to put an Edelbrock linkage kit on there soon
 

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OK ,just making sure as some would run it like that and then wonder why it wont run properly when it fell out.
 

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I don't know for sure, but it looks like the idle screw is screwed in pretty far. Pull the linkage (since the clip is off) and back it out and see if it closes the throttle.
 

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Are the throttle Plates closed all the way, both of them. When you look down in there you should be able to see. If you can't see in there, it only takes just a few minutes and you can have the carb off. Flip it upside down and get a good look at them. It cannot idle fast without an air source. When you flip it upside down all the fuel is going to pour out of the vent tubes.
 

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Discussion Starter #16
Honestly don't know if any of these pictures will help diagnosis my issues, I'm going to take everyone's suggestions & see if I can get to idle down
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Are the throttle Plates closed all the way, both of them. When you look down in there you should be able to see. If you can't see in there, it only takes just a few minutes and you can have the carb off. Flip it upside down and get a good look at them. It cannot idle fast without an air source. When you flip it upside down all the fuel is going to pour out of the vent tubes.
They look closed but I will take the carb off & flip upside down to get a really good look
 

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I can see your choke cam is against the cold idle screw, and that screw may need to be backed off.
 

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I had the same problem with a smaller version of the same carb. Looks like your spring is not under enough tension to close off the carb plates to the proper idle position. Move the spring mounting poiint back or get a shorter spring. I looked for vac leaks forever until I changed the spring tension. That did it.
 

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Discussion Starter #19
Just wanted to say thank you for everyone's input, she's running & idling smooth, adjusting back the fast & cold idle screws & made spring a lot tighter, she sounds a lot better... tried to post a video but site wouldn't accept it, said to large, oh well
 
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