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Hello Barners At an idle my '31 Vicky engine runs smoothly. Yet when I press on the gas, it hesitates and appears to not get enough gas. I have opened up the bottom end of the carb and checked it. The float works fine. Not sure what is causing the stumble. Can you advise me on what next steps to take.

thanks

Paul

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Couple of things to check - confirm that your float is adjusted to the correct height to allow the full volume of fuel into the float bowl as required to run properly. Make sure you have adequate fuel flow from the tank to the carb with no obstructions. With the engine running, turn the gas adjusting valve (GAV) knob counterclockwise 1/4 turn to introduce more fuel. Some of the jets may have become blocked by trash in the fuel and need to be removed and blown out with compressed air, but try the things mentioned above first before doing a complete tear down to see if they make any difference.

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Which carburetor are you running?
Marshall

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regular stock zenith carb

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I use non chlorinated brake cleaner to dissolve the"crap gas" varnish in the jets, then the air gun.

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Did it ever run correctly or is this a new condition?

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Vangogh, can ya paint us a little better picture of your situation? LOL Are you able to drive the car? Does the engine stumble and then smooth out at higher rpms? Does the GAV adjustment recommended above make a difference?

IMHO, your description describes a lean condition when transitioning from idle rpms to low speed rpms. This could be an air leak at the carb to manifold, manifold to block, or a leak at the vacuum port for the wipers??? Between carb halves???

The transition from idle to low speeds is a naturally lean area on the Zeniths. The compensating well, (the hole that the idle jet protrudes down into) serves a dual purpose. It provides fuel to the idle circuit, and when the throttle is opened to go faster, it provides an extra shot of fuel very quickly to prevent the stumble that you describe. The fuel supply / level of the compensating well is controlled mostly by the compensating jet, and partially from the GAV circuit.

If there are no air leaks, I'd expect a problem somewhere between the float bowl and the tip of the cap jet.

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Rob, I think you’re speaking to the wrong ear. ��

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Vangogh will turn his head in the correct direction. :)

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LOL that took a moment to figure out! :) (The evidence points to him only cutting lobe off not the whole ear)

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Check your fuel line from the filter bowl to the carb. Make sure it is not pushed in as far as it can go. This will restrict the flow and cause your carb to starve for gas. The fuel line should end just past the ferrule on the filter end of the gas line and carb end of the gas line.

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Has it sat for awhile? New gas is junk and has a short storage life. Lots of people recommend Sea Foam added to the gas to help preserve it and keep all those little jets and holes in the carb clean. https://seafoamworks.com/product/sea...tem-treatment/ If it is crud in the carb you'll need to add a filter to keep it from happening again.


On the other hand if that Vicky is maroon there is no hope for it call me for proper disposal.

Someday I'll get one......