4 barrel roch. carb question

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cutlassguy

Master Mechanic
Dec 15, 2011
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i adjusted it with the motor off and gave it about an 1/8 gap, but i noticed in the video once i start it, the BF opens ALOT more than what i adjusted it to. should i start it and then adjust the pull off with the motor still running? also isnt something still wrong cuz the motor kicks down and stays there now even tho it was just started? i drove it right after i made that video and by the time i was at the front street, it kicked down and stayed there even tho it was cold. im sure i could have left it alone in HI until it warmed up but i park in a parkade so i basically have to start it and get out. what would make it sputter on full throttle all of a sudden also? never did that before this problem arose. Thanx for stickin with me on this one guys, if it wasnt for your advice im not sure where id be :)
 

Bonnewagon

Lost in the Labyrinth
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Sep 18, 2009
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If you adjust with the motor off, then it's best to use a MityVac to actuate the choke pull-off as that mimics engine vacuum best. Even sucking on a vacuum hose is better than trying to hold it with your finger. Doing it with the engine running and with a vacuum gauge hooked to manifold vacuum gives you real-world operating data and you can quickly adjust for best vacuum reading. The fast idle should stay put while the motor is warming. An electric choke gets hot FAST (that's the whole idea) and if you tap the gas too soon, if falls off too soon and runs crappy because it's still too cold.
 

cutlassguy

Master Mechanic
Dec 15, 2011
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just following orders lol i'll adjust it again with the motor running this time. should it still only open about an 1/8 while running cold? shouldnt the high idle stay on until the motors warm regaurdless of what i do to the peddle? i thought the idea of the choke was to be able to start it and drive right off without any worries...
 

cutlassguy

Master Mechanic
Dec 15, 2011
350
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i adjusted it while it was running to a little more than an 1/8 cuz thats all i could get it to close and its still dropping out of high idle way too soon. i feel like im close now tho cuz atleast its not just stuck in HI...if adjusting the piss out of the pull-off doesnt work, is there anything else i can tinker with? is there any good point to start with like loosening all the adjusting screws and going one by one to achieve a certain setting? whats the first thing you'd do? the choke was fully opened after i drove it for a while tho so atleast i know its not sitting half way all the time.
 

Bonnewagon

Lost in the Labyrinth
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Sep 18, 2009
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How long is it taking for the choke to open all the way? Approximate minutes.
 

cutlassguy

Master Mechanic
Dec 15, 2011
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not really sure, i'll time it next time i head out. thing is i start it in a parkade and cant really let it run for too long but by the time im outside, its already in curb idle. i was out earlier tho and once it warmed up, she ran pretty good. crazy that it went from stuck in high idle to stuck in curb idle :rofl: oh well atleast im learning...
 

Bonnewagon

Lost in the Labyrinth
Supporting Member
Sep 18, 2009
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With a correctly adjusted choke you should be able to start the car, put it in drive, and roll away slowly so you can finish warming up away from where you shouldn't be, all without touching the gas pedal. Emphasis on "correctly".
 

cutlassguy

Master Mechanic
Dec 15, 2011
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i wish i could figure out what im doing wrong so i could get it "correctly" set lol i guess ill just keep adjusting the pull off until something close to what i think is supposed to happen, happens...
 

DoubleV

Royal Smart Person
Feb 25, 2011
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Medina Ohio
Have you adjusted your fast idle setting at all? During a stone cold start, what RPM's is it ideling at? Where does it drop to when you blip the throttle and it falls down to the next lower step of the fast idle cam? What is your curb idle at? State your RPM's in gear and in park.

Have you made sure the secondary lockout lever isn't hanging up or is installed wrong?
 

cutlassguy

Master Mechanic
Dec 15, 2011
350
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nope i havent touched anything aside from the choke and the pull off. in HI she runs at about 1600, curb idle around 1100, and in gear about 600-700. ive resorted to adjusting the pull off a little each time to see if i can find a sweet spot but still no luck.
 
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