168683 Carb for IH434 1967

(quoted from post at 09:31:37 04/23/22) True flooding, when the needle valve fails to close off the fuel and the bowl
overflows, can be caused by the float level set too high, the float is
partially sunk, the needle valve is bad, the seat is loose, or trash is
holding the valve open.

Trash in the needle valve is the most common cause. Sometimes you can flush
it out by closing the fuel valve and running the carb dry. But is the tank is
trashy or flaking rust, it will be an ongoing problem.

That it will idle indicates it may be high float level, or the wrong main
jet, or the main jet has fallen out or loose. Usually flooding means it will
continually drip gas with the engine off, or it will load up and die at idle,
but clear up and run somewhat normal when under load and up to speed.

I would open it up, take a look around. Did it get this way on it's own or
was it worked on? Sometimes kits come with new jets. If the size was not
compared, it may have a jet for an adjustable main, which would make it way
too big. You can usually find the specs online by looking up the carb make
and number.

Also make sure the choke is opening fully and the air cleaner is flowing
freely. Oil bath air cleaners have a wire mesh inside that needs occasional
cleaning, often overlooked. Also check for bird, rodent, insect nests.

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(quoted from post at 12:06:24 04/23/22) have you opened it up and looked at the float as i said?? that is pretty much all u need to know if it sitting level as what float level
means. i dont think its your float. i would say the needle is not seating. post a picture of the float sitting on the needle with top upside
down. you got to start checking stuff before wondering what the setting is. its will be plain to see it its out of wack. i have done piles of
carbs without physically measuring the float. level is level. so as i said post the picture and then i will say yes or no as the float
problem, and dont have to type out a thousand words.

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(quoted from post at 15:33:01 04/23/22) Do you still have the old carb?

You could look and see what size jet it had.

As for setting the idle mixture, the engine needs to be idled down to around
400-450 RPM for the mixture screw to have any effect.

Also check the compression, valve lash, plugs, spark quality, and the points
gap. Weak ignition will look like fuel problems. The carb can only work as well
as the rest of the engine will let it.

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