rochester carb dribbling fuel at idle?

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bobbyt44

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I wanted to thank everybody that answered my last questions! I have replaced the fuel pump and changed the oil and filter.The boat ran at idle for 45 minutes and did not get any fuel in the oil!!!! But i notice fuel dribbling in the carb at idle? Is this something that can be adjusted with the air mixture? This is a new rochester carb. Did not know if this ok or should be looked at?

Thanks for all the help!!!! Bob
 
mpdive

mpdive

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Re: rochester carb dribbling fuel at idle?

Dont know what you mean by dribbling but the lower throttle plate will have fuel being processed/ mixed at idle.
 
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bobbyt44

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Re: rochester carb dribbling fuel at idle?

It looks like gas running into the intake only on one side of the front barrel? the other side looks like a mist?
 
mpdive

mpdive

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Re: rochester carb dribbling fuel at idle?

You should be seeing "atomization" of the fuel. When you put the carb on, did you lightly seat the idle mixture screws and back them out even turns?
 
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dubs283

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Re: rochester carb dribbling fuel at idle?

bobbyt44 said:
It looks like gas running into the intake only on one side of the front barrel? the other side looks like a mist?
Click to expand...

sounds like the idle is too high

there should be zero fuel flowing through the venturis/upper circuits of the carb at idle speed

the idle circuit is located below the throttle plates and is controlled by the idle/air mixture screw(s) and engine vacuum

what is the idle rpm set at now?? it should be roughly 650-700 rpm in gear
 
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bobbyt44

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Re: rochester carb dribbling fuel at idle?

I had a so called mechanic install it ! But is it something that can be adjusted or just have the mechanic return it for another one?
 
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bobbyt44

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Re: rochester carb dribbling fuel at idle?

Well the idle sounds like it is around 550rpm? The engine will die if i put it in gear and raise the rpm up to 2500 and let it return to idle and pull it back to neutral? This on land with a water hose hooked to it.
 
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dubs283

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Re: rochester carb dribbling fuel at idle?

bobbyt44 said:
Well the idle sounds like it is around 550rpm? The engine will die if i put it in gear and raise the rpm up to 2500 and let it return to idle and pull it back to neutral? This on land with a water hose hooked to it.
Click to expand...

sounds like 550 rpm?? what does the tach show??

when was the last full tune-up??
 
mpdive

mpdive

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Re: rochester carb dribbling fuel at idle?

You may want to take it back and have it looked at. It almost sounds like it's dumping a bit. As Dubs mentioned this all takes place under the throttle plate unless your up over the idle circuit. If your physically seeing fuel dribbling, somethings off. Seeing a bit of atomization from the air bleeds would be normal but not dribbling.
 
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Speakrdude

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Re: rochester carb dribbling fuel at idle?

I have the same problem with my Quadrajet. Have rebuilt, readjusted, rebuilt again, new floats, changed float levels. You name, We've tried it. Idle is very smooth at 650, and in gear no problem. Still, fuel is dribbling from both venturies at idle. When you kill the engine, fuel is dumped down intake, causing a vapor to come up from the carb, Thereby causing a hard warm start.
Found a webber on craigslist. Am rebuilding as we speak. I bet problem will be solved soon.
 
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