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Discussion Starter · #1 ·
I've got two Holley's with electric chokes that are both doing the exact same thing on different vehicles. One is a brand new Street Avenger and the other is an older 4160. I even used to have an older 4150 that did the exact same thing. The fast idle will not kick down all the way after the engine is warm, it seems to be hanging up on the last step of the arm. When the motor is still cold, I am able to kick it down but as soon as it warms up I am unable to get all the way off. The arm itself seems to swing freely. I've tried adjusting the fast idle screw out but that hasn't resolved it, it has only lowered the idle. I've tried searching but haven't found what I need. I'm not sure where to turn next, any and all suggestions are appreciated.
 

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Sure.If you loosen the 3 side cover choke housing screws you can rotate the housing.With engine off open the thottle fully.with your other hand or help rotate the choke housing.you will set the choke blade open and counterclockwise-close.that will set the choke blade to your liking.If it's set to far clockwise .it may not be returning all the way closed,keeping idle up(and rich).Also on older carbs,throttle shaft wear will have trouble returning to fully closed as vacumn leaks will keep idle up.They can get egg shaped.sometimes winging the throttle helps it seat.On a new carb that shouldn't be an issue.
 

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Discussion Starter · #3 ·
Sure.If you loosen the 3 side cover choke housing screws you can rotate the housing.With engine off open the thottle fully.with your other hand or help rotate the choke housing.you will set the choke blade open and counterclockwise-close.that will set the choke blade to your liking.If it's set to far clockwise .it may not be returning all the way closed,keeping idle up(and rich).Also on older carbs,throttle shaft wear will have trouble returning to fully closed as vacumn leaks will keep idle up.They can get egg shaped.sometimes winging the throttle helps it seat.On a new carb that shouldn't be an issue.
I have already leaned out the choke to try and compensate and still have the problem. If I lean it out any more it will be too much.
 

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How high is the car idling when it's cold. It almost sounds like the fast idle screw is doing all the controlling of the idle if it still decreases the idle when its warmed up. Is the butterfly opening totally when warmed up. If you had the black cap off of the choke housing did you put it back on right. Inside the choke housing there is a lever that goes into the loop hole of the spring that's in the cap. The regular idle screw should be contacting the stop when the choke is all the way open and the fast idle screw should no longer be affecting the idle speed.
 

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Discussion Starter · #5 ·
How high is the car idling when it's cold. It almost sounds like the fast idle screw is doing all the controlling of the idle if it still decreases the idle when its warmed up. Is the butterfly opening totally when warmed up. If you had the black cap off of the choke housing did you put it back on right. Inside the choke housing there is a lever that goes into the loop hole of the spring that's in the cap. The regular idle screw should be contacting the stop when the choke is all the way open and the fast idle screw should no longer be affecting the idle speed.
On cold start, it actually doesn't want to idle because I backed out the fast idle screw, and when it's hot, it is a few hundred rpm high. This is a compromise until I can get this resolved. So yes, when the engine is warm, the fast idle screw is controlling the idle. High idle sticks when the engine is warm only, not cold. The choke housing is on correct, the butterfly is acting as it should.
 

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Also sounds like a vacuum leak. 1 spot is between the choke housing and the main body. Often the gasket is missing???????????
 

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Discussion Starter · #7 ·
Also sounds like a vacuum leak. 1 spot is between the choke housing and the main body. Often the gasket is missing???????????
I don't believe it's a vacuum leak, the gasket is there and I can get it to idle down by pushing the arm down with my finger, but as soon as you touch the throttle, it catches on the arm again. It is definitely being held up by the arm, I just don't know why.
 

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Look very closely at where the carb meets the manifold. SOMETIMES there is a slight interference between the linkage at the carb.
 

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So what your saying is the fast idle arm is still making contact with the fast idle screw when warmed up. At that point is the choke plate wide open or not. Try giving the carburetor a little gas at the throttle arm and make sure the choke plate is wide open. Hold the plate wide open and let throttle arm go and see what you get for idle now. If that disconnected the fast idle cam from the fast idle screw that would lead me to think you need to turn the black choke cover to lean it out. When I set my own choke when its cold I turn the black choke cap just enough to get the choke plate to close fully. Now if you move your throttle arm just a bit the choke plate should stay closed but the cam arm should drop all the way down to set the fast idle screw. When you start the car the choke plate should open about 1/8" and the fast idle should be set at the spec it calls for. Once the car is warmed up the choke plate should be totally open and the fast idle screw should not be in contact with the fast idle cam arm and the regular throttle adjustment screw should be used to set the regular idle to spec.
 

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Discussion Starter · #10 ·
Look very closely at where the carb meets the manifold. SOMETIMES there is a slight interference between the linkage at the carb.
I had this problem in the past and already made clearance for it, the throttle linkage operates very smoothly with no hangups.

So what your saying is the fast idle arm is still making contact with the fast idle screw when warmed up. At that point is the choke plate wide open or not. Try giving the carburetor a little gas at the throttle arm and make sure the choke plate is wide open. Hold the plate wide open and let throttle arm go and see what you get for idle now. If that disconnected the fast idle cam from the fast idle screw that would lead me to think you need to turn the black choke cover to lean it out. When I set my own choke when its cold I turn the black choke cap just enough to get the choke plate to close fully. Now if you move your throttle arm just a bit the choke plate should stay closed but the cam arm should drop all the way down to set the fast idle screw. When you start the car the choke plate should open about 1/8" and the fast idle should be set at the spec it calls for. Once the car is warmed up the choke plate should be totally open and the fast idle screw should not be in contact with the fast idle cam arm and the regular throttle adjustment screw should be used to set the regular idle to spec.
This seems to make the most sense and I'll check this, but I wouldn't think this would be the case as I have the cap adjusted on the lean "half" of the markings on the housing. It doesn't make any sense to me that the choke adjustment should affect whether or not it opens all the way, I think it should affect only how fast it opens, but maybe I'm wrong.
 

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Any progress.
 

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I have the same problem with the high idle after the eng is hot. I happened to take off the air cleaner cover off with the eng running and the idle dropped right down to normal. WHY? This is on a new holley 670.
 

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I have experienced a problem with the secondary throttle blades hanging open just a little causing the idle to be 100-200rpm higher than set. A blip of the throttle sometimes would snap the blades closed and correct the idle. I bent/adjusted the linkage rod which goes from primary to secondary so as to not allow the rear blades to hang open...just something to look at.
 

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I have the same problem with the high idle after the eng is hot. I happened to take off the air cleaner cover off with the eng running and the idle dropped right down to normal. WHY? This is on a new holley 670.
Could the air cleaner base be rubbing the rod running up to the choke plate.
 

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Discussion Starter · #16 ·
So what your saying is the fast idle arm is still making contact with the fast idle screw when warmed up. At that point is the choke plate wide open or not. Try giving the carburetor a little gas at the throttle arm and make sure the choke plate is wide open. Hold the plate wide open and let throttle arm go and see what you get for idle now. If that disconnected the fast idle cam from the fast idle screw that would lead me to think you need to turn the black choke cover to lean it out. When I set my own choke when its cold I turn the black choke cap just enough to get the choke plate to close fully. Now if you move your throttle arm just a bit the choke plate should stay closed but the cam arm should drop all the way down to set the fast idle screw. When you start the car the choke plate should open about 1/8" and the fast idle should be set at the spec it calls for. Once the car is warmed up the choke plate should be totally open and the fast idle screw should not be in contact with the fast idle cam arm and the regular throttle adjustment screw should be used to set the regular idle to spec.
I worked on both carbs over the weekend. I did check and have about 14V on both while running so that shouldn't be an issue.

On the new carb I found that when cold, any setting of the choke closed it fully, and when hot it didn't appear to lift the cam at any setting. I have leaned it out on two occasions now, with no improvement, and did check when it was idling high, it was hung up on the cam, I was able to push it down manually and it came down to where it should but as soon as I touched the throttle again, it caught on the cam. I'm going to continue leaning it out to see if that fixes it but I don't have much adjustment left.

On the old carb I found that I had to be on the third tick from all the way lean for it to close fully when cold. When hot it appeared I had to be in about the same place in order to get off the cam. I haven't been able to test this one yet but based on my other results I'm not too confident. I did replace the choke cap/coil earlier this summer so that should be good. I still feel like something must be wrong, with both really, the way they are operating.

I have experienced a problem with the secondary throttle blades hanging open just a little causing the idle to be 100-200rpm higher than set. A blip of the throttle sometimes would snap the blades closed and correct the idle. I bent/adjusted the linkage rod which goes from primary to secondary so as to not allow the rear blades to hang open...just something to look at.
I've adjusted both rods too, to make sure they're not hanging open.
 

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Are you sure that on the new carb inside the choke housing that the flat lever that works the choke plate is inside of the loop on the end of the spring. When you move the black choke housing right or left the choke plate should be opening and closing too.
 

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Discussion Starter · #18 ·
Are you sure that on the new carb inside the choke housing that the flat lever that works the choke plate is inside of the loop on the end of the spring. When you move the black choke housing right or left the choke plate should be opening and closing too.
Yes I am sure, it does move and open and close. If it stayed closed I think it would load up and die as it warmed up.

I also found today when I started it after sitting outside in about -10F all day, it started and idled nice but the choke started dropping off with how lean I have it in an effort to get it off high idle when hot. It then kept dying on me and I had to keep it above 1500 for 5 minutes or so otherwise it would die. So the choke is already way too lean but it still won't come off high idle. This carb is seriously cold blooded, what is going on? It's almost undriveable
 

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Yes I am sure, it does move and open and close. If it stayed closed I think it would load up and die as it warmed up.

I also found today when I started it after sitting outside in about -10F all day, it started and idled nice but the choke started dropping off with how lean I have it in an effort to get it off high idle when hot. It then kept dying on me and I had to keep it above 1500 for 5 minutes or so otherwise it would die. So the choke is already way too lean but it still won't come off high idle. This carb is seriously cold blooded, what is going on? It's almost undriveable
Sorry, but it's got me stumped. I've had a few on different cars and never had the problems your running into. Good Luck
 

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Discussion Starter · #20 ·
I called the Holley tech line and explained my problem. The guy I talked to couldn't help me either.

I'm starting to think of other ways to try and resolve this. Anyone have experience with the Holley Choke Delay?

https://www.holley.com/products/fuel_systems/carburetor_components/choke_components/parts/45-267

My thought is that if I install this, I could turn the choke all the way lean (assuming that's enough to get if off high idle) and still have enough choke on cold start. The other thought I had is to put a manual switch in the cab instead of this, accomplishing the same thing, again turning the choke all the way lean, then I would just have to switch power on as it warmed up so the choke would open.

Thoughts?
 
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