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Fuel Over Flowing The Carb

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A few common causes for the fuel overflowing the carb when the petcock is turned on is as follows...

Some of the causes for this would include debris in the tank which would hold the float needle off it's seat and cause the fuel to drain into the engine or out the overflow tube onto the ground.The screen in the petcock should prevent the debris from entering the carb but it sometimes doesn't . The screen could have been removed or come loose at some point.
Cures for this would be to remove and flush out the tank and reinstall it with fresh gas.

It also could be caused by improper float level adjustment.

Check to see if the gas cap is venting or not. If it's not venting, it could be causing pressure as the motor heats up and forcing gas out from the pressure. If you remove the cap when this overflow happens and the dripping stops soon after, then suspect the cap to be bad.
 
A few common causes for the fuel overflowing the carb when the petcock is turned on is as follows...

Some of the causes for this would include debris in the tank which would hold the float needle off it's seat and cause the fuel to drain into the engine or out the overflow tube onto the ground.The screen in the petcock should prevent the debris from entering the carb but it sometimes doesn't . The screen could have been removed or come loose at some point.
Cures for this would be to remove and flush out the tank and reinstall it with fresh gas.

It also could be caused by improper float level adjustment.

Check to see if the gas cap is venting or not. If it's not venting, it could be causing pressure as the motor heats up and forcing gas out from the pressure. If you remove the cap when this overflow happens and the dripping stops soon after, then suspect the cap to be bad.
I'm a newbie, to this anyway, so bear with me please. My 2002 FLH stock with Rienhart true duals is pouring fuel out the air filter when I try to start it with the petcock open and will not start. If I close the petcock and crank it it will eventually start and run until out of gas. If I open the petcock while it is running it will flood out and die. Any help will be apprecitated, thanks.
 
It sounds like your problem is the debris under the needle. You have to open the float bowl and remove the needle to clean it out. Try opening the petcock after you flush out the needle and seat with some carb cleaner to further remove anything that may be in there before reassembling.
 
It sounds like your problem is the debris under the needle. You have to open the float bowl and remove the needle to clean it out. Try opening the petcock after you flush out the needle and seat with some carb cleaner to further remove anything that may be in there before reassembling.

If you have a C V carb there is a screw to empty the float bowl before you take it off, just follow the overflow hose, you should be able to see it
 
Thanks for the help, will try and post back. While I'm here, what is YHO on sea foam? Also do you think going with a Stage 1 kit in the carb would help, the pipes is the only thing not stock?
 
Thanks for the help, will try and post back. While I'm here, what is YHO on sea foam? Also do you think going with a Stage 1 kit in the carb would help, the pipes is the only thing not stock?


Sea foam or Marvel mystery oil are to clean out the carb gunk. Fix the problem first before changing anything else and the stage 1 with your muffles will require rejetting. All the info you need is in the self help area.
 
OK, took the float bowl apart, cleaned & inspected, everything looked good. Blew it with out with air, reinstalled it, and it started up and ran for about 4-5 minutes with the petcock open before it died. Tried to restart and the same as before, fuel poured out the float bowl vent (upper left of intake). It will stop if I close the petcock, any more suggestions?
 
A couple of thins spring to mind on this one could be that the float height is not correctly set and allowing too much fuel through
could be that the float is puntured and filling with fuel rather than floating
or the float needle may need replacing as the taperd end is coated in rubber this makes the seal after a number of years use the rubber coating can go hard and no longer seal
any extra fuel in the float bowl should drain through the overflow which is the pipe that comes up in the middle of the floatbowl so check that the overflow is not blocked

Brian
 
Some have posted about poor running at idle and stalling with fuel flowing out of the carb into the air cleaner or dripping on to the motor.

The cause for this is usually dirt or debris in the needle and seat inside the float bowl from contaminated fuel or a rusty tank etc. It's advisable to clean out the tank if this is the cause of the problem.

The remedy for this is to remove the float bowl, remove the float and the needle and let some gas flow through the inlet by opening the petcock.
Blow it all out and reassemble the carb after cleaning all the parts thoroughly.
It should solve the problem.
 
Some have posted about poor running at idle and stalling with fuel flowing out of the carb into the air cleaner or dripping on to the motor.

The cause for this is usually dirt or debris in the needle and seat inside the float bowl from contaminated fuel or a rusty tank etc. It's advisable to clean out the tank if this is the cause of the problem.

The remedy for this is to remove the float bowl, remove the float and the needle and let some gas flow through the inlet by opening the petcock.
Blow it all out and reassemble the carb after cleaning all the parts thoroughly.
It should solve the problem.
I have the same problem on my 2005 883 Sporty.
I have replaced the fuel valve, needle and seat and the jet in the carburator, but it is still leaking fuel through the air cleaner. Any suggestions?
 
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