Team Chevelle banner
1 - 20 of 20 Posts

·
Registered
Joined
·
438 Posts
Discussion Starter · #1 · (Edited)
I can't get any adjustment with my electric chokes fast idle screw no matter which direction I've turned it.
I even have it so it's tightened all the way and it still does not touch the steps on the cam except for the highest one. When I blip the throttle the cam will move all the way as it should to stop the fast idle.
The choke flap opens and closes as it should as the motor warms up. As the motor cools down the choke slowly closes when the motor is off, I've watched it with the air cleaner off.
Am I doing something wrong? From what I've gathered there's only 2 adjustments the fast idle and the choke flapper.
It worked correctly the 1st couple of times I started my new motor and that was it.
Quick fuel brawler 850 mech secondaries.
 

Attachments

·
Banned
Joined
·
2,671 Posts
Wish I could help ya . I'm not bad with carbs but I'm really not up on the electric chokes .
I either buy the carbs with no choke or when I get em with a choke I take it off of the carb
 

·
Registered
Joined
·
438 Posts
Discussion Starter · #4 ·

·
Registered
Joined
·
438 Posts
Discussion Starter · #6 ·

·
Registered
1970 SS 396 25-C, 1966 SS R-R
Joined
·
894 Posts
I think it should close completely then the pull off opens it slightly 3/16 to 1/4 after start. Is the cam positioned with the highest (thickest) part toward the screw. While holding the choke shut open the throttle about 1/2 way then let off the throttle. Then let off the choke plate and see what happens.
 

·
Registered
1965 Malibu SS
Joined
·
157 Posts
I have a similar issue with mine. I wondered if some how they installed too short of a fast idle screw. I never followed up on it.
 

·
Registered
1971 Chevrolet Chevelle Malibu
Joined
·
7,545 Posts
With the air cleaner off and the engine off and cold just move the throttle linkage enough to and see if the carburator butterfly snaps closed all the way. If it doesn't there are 3 screws that hold the black cap from spinning. Loosen those and with the throttle linkage held off the stop turn the cap so the butterfly closes all the way. Retighten those 3 screws and start the car and the butterfly should open about 1/8" and you should have a fast idle then. Once it warms up if you hit the throttle it should kick the carb off the fast idle and go to the rpm the throttle stop screw is set at.
 
  • Like
Reactions: LeoP

·
Registered
Joined
·
438 Posts
Discussion Starter · #11 ·

·
Registered
Joined
·
438 Posts
Discussion Starter · #12 ·
With the air cleaner off and the engine off and cold just move the throttle linkage enough to and see if the carburator butterfly snaps closed all the way. If it doesn't there are 3 screws that hold the black cap from spinning. Loosen those and with the throttle linkage held off the stop turn the cap so the butterfly closes all the way. Retighten those 3 screws and start the car and the butterfly should open about 1/8" and you should have a fast idle then. Once it warms up if you hit the throttle it should kick the carb off the fast idle and go to the rpm the throttle stop screw is set at.
I'll try this, but the fast idle screw is currently all the way in. Should I leave it that way for now while doing what you mention?
 

·
Registered
1971 Chevrolet Chevelle Malibu
Joined
·
7,545 Posts
I'll try this, but the fast idle screw is currently all the way in. Should I leave it that way for now while doing what you mention?
Didn't you say the only step the screw hits the cam on is the highest one. If so if your butterfly isn't closing all the way to start with the fast idle screw may already be away from the highest step. I would set the butterfly up like I said and leave the screw where it is. If you get a fast idle and you think it's too high you can always back that screw off. The black cap should have a knotch in the closest part that touches the choke body and should be set around the center knotch on the choke body. The fast idle screw dosen't nessasarily have to hit all the other cam steps to work as long as it's hitting the highest one. The only thing I can think of when you say it seemed to work right the first couple of times is either the black cap is loose and turning or the spring in the cap lost some of it's tension from heating up and cooling down and needs to be reset by turning the cap counter clockwise.
 

·
Registered
1971 Chevrolet Chevelle Malibu
Joined
·
7,545 Posts
In your first picture the notch on the black cap looks like it is near one of the screws. You have to loosen the 3 screws that hold that cap to be able to rotate the cap. If that's the mark it is way off and you should turn the black cap counter clockwise so it is more to the top of the choke body and lined up close to the center mark on the choke body. I've found on my cars with Holley Carburators when setting up the electric choke those notches normally work best when the notch on the cap is off center by 2 notches clockwise but cars can be different.
 

·
Registered
Joined
·
14,228 Posts
Choke has to be engaged for that screw to do anything, in case it wasn't mentioned.

That being said, I don't have any luck with non-Holley carb electric chokes working right. I'm d!cking with a neighbors QFT electric choke that just doesn't want to cooperate.
 

·
Registered
Joined
·
438 Posts
Discussion Starter · #17 ·
Ok, just tried the above and still no luck.
I decided to turn the choke housing in the center where it is set out of the box and start from there.
However I realized now, how tight should I make the fast idle screw when it contacts the cam? I have it so it just touches and there is no change.
So I move the arm below that it makes contact with and it seems that I should tighten the screw kinda tight so the cam will have enough tension on it to move the arm below, which will raise the idle. I just do not want to tighten it too much if that is something I should not do.
I apologize for my ignorance on this, I never had an electric choke before.
 

·
Premium Member
Joined
·
1,001 Posts
Adjusting The Fast Idle Speed Screw

b) With the engine off, turn the throttle to its side wide open position and hold it there. This will expose the fast idle set screw behind the choke housing. c) Using a ¼ inch open-ended wrench, turn the screw clockwise to increase the RPM or counter clockwise to decrease to RPM.
 

·
Registered
1971 Chevrolet Chevelle Malibu
Joined
·
7,545 Posts
When I set mine up I make sure the throttle linkage is away from the throttle stop so the butterfly will be able to close. The car should be dead cold at this point. I then turn the black cap counter clockwise till the butterfly just closes off the opening of the carburator totally. At that point the fast idle screw should be touching the cam on the highest step. When you start the car the butterfly should open about a 1/8" but still the fast idle screw should have contact with the highest step on the fast idle cam. If your screw isn't all the way in you can turn it in to bring the fast idle up.
 

·
Registered
1965 El camino. Originally regal red with a 283 and rear air ride suspension
Joined
·
42 Posts
With the air cleaner off and the engine off and cold just move the throttle linkage enough to and see if the carburator butterfly snaps closed all the way. If it doesn't there are 3 screws that hold the black cap from spinning. Loosen those and with the throttle linkage held off the stop turn the cap so the butterfly closes all the way. Retighten those 3 screws and start the car and the butterfly should open about 1/8" and you should have a fast idle then. Once it warms up if you hit the throttle it should kick the carb off the fast idle and go to the rpm the throttle stop screw is set at.
What HKalin said.
 
1 - 20 of 20 Posts
Top