Carby too lean or to rich?

linnix13

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so i have a 33cc zooma, anyways, it has one ajustment screw on the carb, i asume in is lean and out is rich, with it turned 1 1/2 out it bogs in the lows but is great in the highs, if i turn it out 2 times it runs great in the lows but then gets really rumbly in the highs, i tried in between but it seems to be either rumbly or boggy, and there is never exhaust smoke, not on 2 turns or one and a half,
 
It depends on where the screw is located on the carb.
Typically, if the screw is located near the air cleaner then it controlls air flow.
If the screw is closer to the engine then it controlls fuel.
This is in no way a steadfast rule though.
I would set the screw to run best at low speeds and then see what adjustments are possible for just the hi speed fuel circuit. Perhaps you need a different fuel jet? If your carb has a jet needle, you may need to adjust the clip setting.
 
It depends on where the screw is located on the carb.
Typically, if the screw is located near the air cleaner then it controlls air flow.
If the screw is closer to the engine then it controlls fuel.
This is in no way a steadfast rule though.
I would set the screw to run best at low speeds and then see what adjustments are possible for just the hi speed fuel circuit. Perhaps you need a different fuel jet? If your carb has a jet needle, you may need to adjust the clip setting.

its a dead simple carb, it has no pin ajustments, one screw, on the bottom of the carb, next the the 2 fuel lines,(they both go to the gas tank but one sucks and one blows)
 
OK. That is near identical to the carb that came on my Go Ped.
Look at the center of the black plastic throttle cam, where the inner cable attaches to the carb. There should be a tiny little screw.
That controls the low speed circuit mixture. The screw on the side of the carb is like an adjustable main jet. It controls the high speed mixture.
 
OK. That is near identical to the carb that came on my Go Ped.
Look at the center of the black plastic throttle cam, where the inner cable attaches to the carb. There should be a tiny little screw.
That controls the low speed circuit mixture. The screw on the side of the carb is like an adjustable main jet. It controls the high speed mixture.


oh ok, so how abouts do i adjust it? the problem was that it would bog at full throttle and only drive on 3/4ths full, and it wouldent climb hills, turning the high speed mixture fixed the bogging but it hampers the highs,
 
OK. That is near identical to the carb that came on my Go Ped.
Look at the center of the black plastic throttle cam, where the inner cable attaches to the carb. There should be a tiny little screw.
That controls the low speed circuit mixture. The screw on the side of the carb is like an adjustable main jet. It controls the high speed mixture.

so do i turn the low speed counter clockwise or clockwise?

and how mutch?
 
There should be 3 screws total.
1 idle speed
2 idle mixture
3 high speed mixture
 
I am holding that exact carburetor in my hand right now.
The screw by the fuel hose barbs is the high speed screw. Turn it out to add fuel, in to reduce fuel.
Looking down at the black plastic cable cam there is a brass screw with slots on either side of it. Do NOTtry to turn the big brass screw. It is hollow in the center with a super glue filler in it.
Pick put the glue as best you can, or, I burrned it out with a small "pencil" torch. It lights up really fast and "poof" it is all gone. It burned so fast the large brass screw never had a chance to get hot enough to melt the plastic any.
Be carefull to only apply the flame to the center of the brass. Do not get it near the plactic.
After you remove the glue plug you will need a jeweler's screwdriver to turn the tiny screw down in there.
Out to add fuel to the idle circuit.
In to reduce the fuel.
There really is no midrange adjustments on these carburetors.
 
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