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File: 2012-11-17_200623_quadrajet_choke_housing.jpg (24KB, 320x240px) Image search:
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Hey guys I have some questions regarding a rochester quadrajet jet carb. My camaro had been running like crap the last few days and I got under the hood to Check it out and the choke adjustment screw was completely missing. This is a Google Image for reference but the three little safety screws were completely missing and the big plastic adjustment notch was out of the carb the spring was out and the choke was stuck wide open. I had trouble starting the car up to this point and it ran like absolute dog shit idling erratically and surging under smooth throttle application.
I put the choke screw back in and set it as best I could and then return did my air fuel mixture on the two front screwside because someone said it would be off now that the choke spring had been fucked.
Can someone explain to me how these mechanisms work particularly the choke spring, how that would cause my idle to be garbage? And how I should properly adjust them? I did it in an autozone parking lot on the fly?
Do I adjust the choke while cold and drive for 30 minutes to see if it opens up on its own? What about air fuel screws when do I adjust those? When it's hot?
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>>16224440
How about selling this out dated piece of garbage and buying yourself a car that you don't have to adjust the fucking choke on? Seriously why do you people still bother with these cars?
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>>16224452
Some people like old carbureted veeyates man
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Bump please
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>>16224440
OK you set the choke thermostat to where the choke plate is closed at room temp. That vacuum diaphragm just to the front of the choke is a Choke Pull Off and its job is to pull the choke plate open about 1/8 inch after the engine starts (its secondary job is as a damper for the secondary air valve so they don't open so fast and cause a bog). You also have to have the fast idle speeds set but most people don't fuck too much with that so it should still be in the ballpark. Keep in mind tha the chokme thermostat MUST have heat applied or it won't open. Older ones like in your pic have a metal tube that connects to a stove on the manifold and hot air is sucked through that tube over the bimetal coil in the choke thermostat. Newer ones use an internal electric heater that get 12v supplied through an oil pressure switch. If there's no heat the choke will stay on and the thing will run terribly.
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>>16224440
As for the idle mixture screws you adjust those for best idle quality when the engine is up to temperature. Newbs can use a vacuum gauge and adjust for highest vacuum until they get a feel for engines that are a bit "off". You may have to go back and forth with idle mixture and idle speed a few times.
FWIW QJ's are very sensitive on the primary side and it doesn't take very much throttle opening to get the main system feeding on the primary side which negate any effect of the idle mixture screws. If the idle mixture screws aren't having much effect then it's likely the throttle is open too far due to compensating for something else like retarded timing with the idle speed screw.
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