OT: carburetor problems

This is just a general carb question, hope someone is kind enough to answer... (no luck so far in the Jeep n.g.)
actually has to do with a CJ7 Jeep, 258, stock Carter BBD carb rebuilt 6
years ago. If I'm at idle and just barely feather the gas it almost wants to stall out. A nice firm press of the gas pedal and it accelerates fine. Upon further inspection, I noticed that the fuel that comes out of the 2 venturi nozzles in the carb dribble out unevenly when throttle is applied... now if I remember correctly TB injectors are supposed to spray fine even mists into the engine. Does this same principle hold for carburetor fuel delivery?
I went ahead and removed the venturi cluster, cleaned out the idle pickup tubes, venturi nozzles, and anything with a passage with some guitar wire. They weren't plugged and I got the same result afterwards.
I'm thinking that when feathering the gas pedal, the uneven dribble of fuel causes it to run rich and stumble. Is this normal carb behavior or am I looking at some sort of internal carb wear. Thanks for any info.
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Not familiar with Carter carbs. The Holley 650 Spreadbore had a change-over slot that took it from idle to street operation. The trick with those carbs (to eliminate change-over problems) was to drill a small hole, in the throttle plate, in line with the change-over slot. Don't know if any of this applies to a Carter though.
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Take it with a grain of salt, but hayne's Rochester carb manual says it's supposed to dribble. That's called an "emulsion" of air and gasoline. I suppose that fits the definition of "emulsion" As the other poster stated, I bet there is something up with your off-idle ports. These should look like "breathers" of sorts that are right around the level of the butterfly valves.
~KJ~

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I won't claim to be an expert by any means. I do wonder how old the carb is initially. carters that i have used tend to be bullet-proof but I have replaced a Holly 4 barrel after a fresh rebuild just because the carb was worn out. The carb body gets a fair amount of abuse and use. The holly was sucking air though the body at the pivot points of the choke and trottle valves. Could not adjust properly. the carb was worn out. had 120k. Ran lots better after replacement. Cost $500 . also from time to time two venturi ports on the top of the carb or breather holes about the size of a pencil led just under the air cleaner gasket would clog up and affect the carb tuning. I would carry a can of carb cleaner with spray tube and stick it in these two holes while it was running and spray. seemed to want to stall,but then would run great. hope not to confuse you but a new carb might be the trick.
On Fri, 28 Nov 2003 22:29:33 GMT, "KJ"

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btk wrote:

years old, it was rebuilt 6 years ago by a local carb shop. I'd even venture to say it's the original carb put in back in '84. The vehicle now has just over 140k miles. We're most likely going to replace the carb, so any advice on 'new' vs. 'remanufactured'?
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KJ wrote:

venturi nozzles I mentioned. At idle, they are inactive, but once the throttle is hit they dribble the gas.
Thanks
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Well there are idle ports, off-idle ports, and main/running/high speed ports.
Idle ports dribble when idling, off idle ports start to work when the butterfly's slowly opening, slowly taking over the idle jets, but doing what the main jets can't yet (not enough vacuum up past the butter fly for them to work yet) eventually drying up and turning it over to the main ports. This is as best I can remember, I read it just recently but I don't have the book with me or I'd copy this portion word for word for ya. Just remember to take this with a grain of salt.
~KJ~

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You confused me when you mentioned TB injectors, i'm still assuming this motor is carbureted and not injected. No it's not normal for fuel to dribble out of the emulsion tubes at any throttle position or RPM. There is suppose to be a check valve (steel ball) and gasket under the spray head, it sounds like that check valve is missing and allowing fuel to dribble out into the venturi. -- George S.

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Mad Dog wrote:

there should be an even spray pattern coming from the venturi nozzles.

gasket and steel ball in place. I'll probably go back and check to see if anything with the ball or gasket is awry. The plan, eventually, is to replace the carb. Thanks for the info.
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