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My #1 carb is still flooding. The plug is sooting up, idle drops to 500, and on throttle, gas leaks out the carb, along the choke shaft (?) it seems. Carbs are spotless inside, and were Honda dealer rebuilt. Today I put an OEM float, valve needle and seat from my old carbs in. Float height to spec. Put a different float pivot pin as well. Seems like it's operating fine. Then when i fire it up, gas starts seeping into the air chamber of the carb plenum as i look down through the bike, then dripping from the carb body onto the engine, as i look from the side. It's intermittent. No smoke out exhaust. I got 50mpg riding two up for a few days, then it would flood/leak like hell. HELLLLPPP! Is my carb plenum gasket hooped? Or maybe the fuel o-ring on the #1 carb, where it joins the carb plenum? This would make sense. I think even dealers skip this deep a rebuild (float parts were aftermarket).
 

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mag wrote:
My #1 carb is still flooding.It's intermittent.I got 50mpg riding two up for a few days, then it would flood/leak like hell. HELLLLPPP!
The fact that it's intermittant would lead me to believe it's the #1 carb float valve. If a gasket or seal was leaking I can't see why it would be intermittant.
 

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Why would the float valve leak after being replaced with an OEM one? Also, the bike stalls when running and put on the side stand. Just took it out for a run and it goes like stink, idling perfect now. Slight stumbling, but no hesitation on throttle like before.
 

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mag wrote:
Why would the float valve leak after being replaced with an OEM one?
Can't say, but the intermittent part of your problem sounds more like something moving somewhere. I can't see a gasket leaking part time unless it's temperature related. Think about it, #1 carb is flooding. Gas is leaking out of #1 carb. What happens with a leaking float needle? I've had this problem before on an aircraft carb, in that case there was a slight bind in the float to needle valve link and once in awhile the needle would get just slightly cocked and not seat down fully, result in an aircraft is gas dripping out on the ground since the carbs are up draft and mounted underneath the engine.

If you could catch it when it's flooding, carefully disconnect the fuel line without jarring the carb as far from the carb as you can and attach a Mity Vac or other hand air gauge and pressurize the fuel line to 3 or 4psi you could see if the pressure holds or leaks down. If it holds, then the float probably isn't the culprit. You could just hook onto the fuel line at the tank, that would test all four carb floats at once, if there was a leak down then you'd have a pretty good idea it was #1.
 

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Well, it makes sense it's not the carb plenum gasket. when i had carbs off the bike, i poured gas in the air chamber, and watched for seepage. I guess the flooding float bowl will seep out wherever it can? Guess i'll take the carbs off again, and put a brand new OEM float valve seat in there. Good idea with the air leak down test. That would test my fuel pump pressure too?
 

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mag wrote:
Well, it makes sense it's not the carb plenum gasket. when i had carbs off the bike, i poured gas in the air chamber, and watched for seepage. I guess the flooding float bowl will seep out wherever it can? Guess i'll take the carbs off again, and put a brand new OEM float valve seat in there. Good idea with the air leak down test. That would test my fuel pump pressure too?
Yep! I heartily recommend a Mity Vac or other brand of hand vacuum/pressure pump and gauge. They come in handy for a variety of purposes. Most auto parts stores sell them usually under $50US. If you have the evquivalent of a Harbor Freight store they have a version around $30 that comes with a brake bleeder bottle too. The things can be a live saver when bleeding hydraulics. You can also use the thing as a manifold vacuum gauge for diagnosing engine problems.
 

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thanks, paul
 

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This was something that concerned me after reading some negative accounts about aftermarket Kits having leaking float valves.

I used OEM but decided not to take any chances so I came up with a procedure for testing them.

I inserted (after cleaning) a fuel crossover pipe into the carb and blocked off the other passages. I turned the carb upside down and proceeded to blow into said crossover pipe to see if any air leaked past the seal. I was unable to blow into the chamber (a good thing). You have to remember that air is thinner than gasoline (petrol) and is more apt to find a leak. I also used a small artists bush soaked in a light soap/water solution to dab inside the valve/seat cavity to visually detect any leaks and there were none. After that I blew out any traces of liquid.
 

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chumbiwumba wrote:
I inserted (after cleaning) a fuel crossover pipe into the carb and blocked off the other passages. I turned the carb upside down and proceeded to blow into said crossover pipe to see if any air leaked past the seal. I was unable to blow into the chamber (a good thing).
Very good, turning the thing upside down and trying to blow through the valve is an old and honorable method of testing the float valve. It works well on small carbs with light floats but is doubtful with large and heavy floats. Being the Goldwing floats are small and light it's a good method. I knew a guy who inflated a small balloon on the end of a piece of fuel line and attached that to the float valve. Lots of good ad hoc testing methods a guy can come up with.
 

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mag wrote:
Well, it makes sense it's not the carb plenum gasket. when i had carbs off the bike, i poured gas in the air chamber, and watched for seepage. I guess the flooding float bowl will seep out wherever it can? Guess i'll take the carbs off again, and put a brand new OEM float valve seat in there. Good idea with the air leak down test. That would test my fuel pump pressure too?
Mag, the easy way to test a carb needle & seat is to insert the needle into the seat,, then place the threaded part of the seat between your lips & suck on it,, as soon as you have a decent vacuum applied place the tip of your tongue over the threaded end of the seat.. If the needle/seat is sealing the needle & seat should stay stuck to your tongue for a while.. If it falls right off it is a leaker. I test ALL the new needle & seats installed as the quality control is pathetic on some of the carb parts sold now. If a metal tipped needle you can lap it into the seat with a fine pumice, if a vitron tipped needle you need to find a new one.

Another place to look for an intermittent leaking carb needle is to make sure the float over-travel tang is set so the float can't drop all the way into the float bowl. If the float drops too far the needle can **** in it's seat & not allow the float to raise & close the fuel flow off.

Twisty
 

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Hi twist. Both those sound plausible, especially the latter. Question: why would the bike stall when idling and put on the sidestand. If that one carb is flooding for whatever reason, is that enough? Seems odd. The bike bogs down and then quits. Otherwise, it seems to idle great and runs/starts great now. No noticeable leak anymore externally. I'll put a new plug in and see what happens. Also, after replacing the float pivot pin, float and valve set from my OEM parts off the old carbs, I'm convinced that there is a casting flaw/burrs on the float pivot 'towers', causing the pin to warp, and whatever float i put on to have 'sticky' travel up and down.
 

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I used to test float valves with suction when they were steel needles and brass seats, but with the soft tipped needles, the suction tends to pull them down and seal where the lighter action of a float might not.
 

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mag wrote:
Hi twist. Both those sound plausible, especially the latter. Question: why would the bike stall when idling and put on the sidestand. If that one carb is flooding for whatever reason, is that enough? Seems odd. The bike bogs down and then quits. Otherwise, it seems to idle great and runs/starts great now. No noticeable leak anymore externally. I'll put a new plug in and see what happens. Also, after replacing the float pivot pin, float and valve set from my OEM parts off the old carbs, I'm convinced that there is a casting flaw/burrs on the float pivot 'towers', causing the pin to warp, and whatever float i put on to have 'sticky' travel up and down.
Mag, usually when a Wing loads up & stalls when leaned over on the side stand it is due to either a high float (carb fuel level), or one or more carbs that have a higher than normal fuel level... Yes, one carb acting up (especially rich) can cause a stall. Remember that not only does a high fuel level cause a fuel dumping & rich action the higher fuel level plugs off the air bleeds & takes the enleaning air from the pilot jet channels.



I'm convinced that there is a casting flaw/burrs on the float pivot 'towers', causing the pin to warp, and whatever float i put on to have 'sticky' travel up and down.
Very possible, those float pin casting pinions are easily damaged if the pivot pin is forced or driven out with force, or the in the wrong direction.

Twisty
 
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