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If the car runs fine otherwise, I would check for vacuum leaks around the base of the carb, since you had it off to rebuild it. I’d also check the mechanical timing of the engine just for giggles. To adjust the electric choke, there should be probably 3 screws around the plastic choke spring housing. Loosen these and turn the choke housing whichever direction it needs to be, tighter or looser. Don’t turn it far, like a 1/16th of a turn at most, and see where you are at. You don’t want the choke plate completely closed when it’s set, as some air needs to get past it. The specs should be in the rebuild kit.
to set the choke you fully warm the engine pull the air filter assembly off and see if it is fully open. if not then reset it by loosening the 3 screws and turn till it is fully open. you cannot just “guess” where it should be. the choke will not change just because you hit the brake or turn a corner. it would more then likely be in the float ajustment. a model number of the carb would be helpfull here.
Quoted From moparfan:
to set the choke you fully warm the engine pull the air filter assembly off and see if it is fully open. if not then reset it by loosening the 3 screws and turn till it is fully open. you cannot just “guess” where it should be. the choke will not change just because you hit the brake or turn a corner. it would more then likely be in the float ajustment. a model number of the carb would be helpfull here.
Right, ‘cuz the float level will just change when you hit a bump. Dude, he said he rebuilt the carb. There are usually specs on the gap with the choke closed when you rebuild it. I didn’t say to guess. And why would the float level be an issue when you are having problems with stumbling when you get off the gas? Move along.
Anyway, I found a Holley link that goes over adjustments for a Holley 4 barrel. The 4150s and 4160s are really similar, and the most common. One has an extra metering block, and 4 idle screws instead of two. I forget which is which.
http://www.holley.com/data/Products/Tec … 7948-5.pdf
Good luck.
Quoted From Beefy:
Right, ‘cuz the float level will just change when you hit a bump. Dude, he said he rebuilt the carb. There are usually specs on the gap with the choke closed when you rebuild it. I didn’t say to guess. And why would the float level be an issue when you are having problems with stumbling when you get off the gas? Move along.
Anyway, I found a Holley link that goes over adjustments for a Holley 4 barrel. The 4150s and 4160s are really similar, and the most common. One has an extra metering block, and 4 idle screws instead of two. I forget which is which.
http://www.holley.com/data/Products/Tec … 7948-5.pdf
Good luck.
if the floats are set to low for what ever reason or some dirt is plugging the floats up some you would run out of fuel turning or stoping or any movement that would slosh fuel around or not having the vent tube fuel is sloshing out the top and back into the throat of the carb. again making it bog when stoping or turning like STATED IN FIRST POST! also if it runs and drives fine other wise and suspects the choke is not open all the way then you need to see for sure FIRST if it is opening all the way or not! experience has taught me just because it was set right cold does not mean it will open all the way when warm. this greatly depends on out side temp at the time it was set. colder it is the more pressure the spring inside will force the choke to close. if you had been a mechanic as many YEARS as i have you would know this! so stay in school and you will get there. i think you need to go back and read the problem again.
also you need to stop fallowing me around the forum trying to start trouble!
Quoted From moparfan:
to set the choke you fully warm the engine pull the air filter assembly off and see if it is fully open. if not then reset it by loosening the 3 screws and turn till it is fully open. you cannot just “guess” where it should be. the choke will not change just because you hit the brake or turn a corner. it would more then likely be in the float ajustment. a model number of the carb would be helpfull here.
I’ve never heard of setting a choke when the engine is warm and honestly I think it’s better if you adjust it when it’s cold but you need to get the plate tension just right for it to work properly.
That said you could have a problem with the linkage that actually could be the result of a misadjusted choke, if the choke isn’t adjusted correctly when the engine is warming up the fast idle screw will not set properly. In short I would check your choke adjustment first before making other adjustments.
Quoted From EricTheCarGuy:
I’ve never heard of setting a choke when the engine is warm and honestly I think it’s better if you adjust it when it’s cold but you need to get the plate tension just right for it to work properly.
That said you could have a problem with the linkage that actually could be the result of a misadjusted choke, if the choke isn’t adjusted correctly when the engine is warming up the fast idle screw will not set properly. In short I would check your choke adjustment first before making other adjustments.
i think my statement was miss understood. setting when cold is good for a pre set. but if the out side temp is high enough when set cold the choke may not open fully after the engine has fully warmed up. (ELC chokes are still affected by heat) so in the end you still need to make sure the choke will fully open when warm. if not it must be adjusted again. resetting it again cold back to the same place you did the first time will not get it to open fully. this may also be a sign of the choke going bad. some times thing don’t happen like they say it should in a book. hope that clears things up a bit. note i live in a state that summer temps hit 100+
ok thanx for all the input guys here is some more info on the carb its not a 650cfm its a 600 and model #65-80457. i have also noticed when i was lookin for the modle # i saw that the jets on the 2 barrels on the rear of the carb where dripping gas(at idle). is this normal? i also have the brake booster connected to the main vacuum line on the back of the carb is this ok or shout it be directly on the intake itself. i know have alot of questions but any and all help is very appreciated.
Quoted From a76montecarlo:
ok thanx for all the input guys here is some more info on the carb its not a 650cfm its a 600 and model #65-80457. i have also noticed when i was lookin for the modle # i saw that the jets on the 2 barrels on the rear of the carb where dripping gas(at idle). is this normal? i also have the brake booster connected to the main vacuum line on the back of the carb is this ok or shout it be directly on the intake itself. i know have alot of questions but any and all help is very appreciated.
There should be no fuel delivery to the secondaries at idle and certainly no dripping. I think the dripping is most likely caused by a problem in the rear float housing. The needle and seat may need to be renewed, the float may need adjustment, it may need replacement, and you need to check for proper operation of the secondaries after you’ve checked everything else. This is done by warming the engine, then opening to wide open throttle with your hand, observing the secondary throttle. When you do this, the ignition timing has to be correct or you may get a backfire up through the carb. You also need to check to see the secondary throttle is CLOSED at idle.
Also, you may have a bad power valve on the primary side. You can check by removing the front float bowl, removing the power valve and sucking on it. If it’s good, it will open.
Take care of the problem with the fuel delivery to the secondaries first. If everything works at that point, you don’t need to check the power valve.
I’ve had to live with a few electric choke carbs and I’d rather have a manual choke. I live in California and have adjusted electric chokes in Southern CA where the summer temp goes over 100. I’ve lived in Northern CA where the temp is 10 degrees cooler. I’ve never had to adjust an electric choke for below freezing temp. Here’s what I do – Set the choke in the summer. I disconnect the wire to the choke and let it cool off completely, then I open the choke halfway, then I connect the choke wire and start the engine. If it stumbles, I give it more choke, but I don’t recall having to do this. With the engine running, I observe the choke opening. It may take around a minute. This works for me in hot weather. When the weather cools off, I will readjust the choke.
If you’ve had an old vehicle or a motorcycle with a manual choke, you know what you want out of your choke.Quoted From yarddog1950:
There should be no fuel delivery to the secondaries at idle and certainly no dripping. I think the dripping is most likely caused by a problem in the rear float housing. The needle and seat may need to be renewed, the float may need adjustment, it may need replacement, and you need to check for proper operation of the secondaries after you’ve checked everything else. This is done by warming the engine, then opening to wide open throttle with your hand, observing the secondary throttle. When you do this, the ignition timing has to be correct or you may get a backfire up through the carb. You also need to check to see the secondary throttle is CLOSED at idle.
Also, you may have a bad power valve on the primary side. You can check by removing the front float bowl, removing the power valve and sucking on it. If it’s good, it will open.
Take care of the problem with the fuel delivery to the secondaries first. If everything works at that point, you don’t need to check the power valve.
I’ve had to live with a few electric choke carbs and I’d rather have a manual choke. I live in California and have adjusted electric chokes in Southern CA where the summer temp goes over 100. I’ve lived in Northern CA where the temp is 10 degrees cooler. I’ve never had to adjust an electric choke for below freezing temp. Here’s what I do – Set the choke in the summer. I disconnect the wire to the choke and let it cool off completely, then I open the choke halfway, then I connect the choke wire and start the engine. If it stumbles, I give it more choke, but I don’t recall having to do this. With the engine running, I observe the choke opening. It may take around a minute. This works for me in hot weather. When the weather cools off, I will readjust the choke.
If you’ve had an old vehicle or a motorcycle with a manual choke, you know what you want out of your choke.very well explained! much better then i could of done. only thing i want to add is while checking the floats make sure non of them are taking in fuel because of a hole in it.
When you open the throttle all the way with your hand, the primary throttle will open directly with the movement of your hand on the external linkage on the driver’s side of the carb. The secondary throttle is vacuum operated on that Holley so the engine will reach a certain RPM and it will roar like a lion, then the the secondary throttle will open, by means of vacuum, or indirectly, and the engine will gain RPM and scream like a raped ape!
At this point, you will let go of the throttle to avoid over-reving the engine.
Importantly, with a 4 barrel carb that has vacuum operated secondaries, the secondaries will not open without vacuum. In other words, they they will not open if the engine is not running.
This is confusing – A 4 barrel carburetor like yours has two throttles, butterfly throttles in the base plate of the carb which lives directly above the intake manifold, but everything connected to those throttles, such as the external linkage as well as the “gas pedal” inside the vehicle, is also called a “throttle”.
In other words, if you drive like Grandma, you control the primary throttle with your wee footsie on the gas pedal and the secondary throttle never opens. When the teenage grandson borrows the car, he nails the pedal to the metal and the primary throttle opens all the way, then the engine gains RPM until vacuum opens the secondary throttle and the police pull him over.
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