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Discussion Starter · #1 ·
Manual says float top should be 14.7mm above float chamber mating surface when inverted. Mine was at least 5mm below that, and I could not get it to that by bending the tang.

As the manual also says fuel level should be 2-3mm above float chamber mating surface when upright and level, I opted for that method. I put a clear tube on the drain and have been working trial and error to get it to that.

Problem is that even with fuel level as much as 10mm below the mating surface, I'm still getting a continual drip from the overflow.

Any ideas or suggestions will be appreciated.
 

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First thing to check is the needle jet condition, if it has a flaw it will still let gas in the bowl not seating fully. Also, always a good idea to throw the floats in a cup of water when you have them out to make sure there are no pin holes.
 

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Discussion Starter · #3 ·
Good ideas; thank you. Had checked the float needle point, it's in good condition. Had also replaced both o-rings and they seat tightly Shaking the float gives no indication it's taken on fuel. And it had been starting, idling, and revving smoothly.

The only reason I checked it is because I'd noticed some leakage from the overflow just sitting on a level surface, and saw fuel/air blowing out the carb intake when revving w/ the airbox off; was afraid it'd be running rich if the float was too high. I had bought this w/ problems and just previously restored spark, but didn't have any experience w/ it other than w/ it broken.

Filled the lower float chamber w/ fuel to see of it was getting into the drain around the base of the pipe. There was no leakage. The overflow port is well above what is showing outside in the clear tube, about 10mm above the mating surface. Only thing I can come up with is that the clear tube method is not giving me a true level.

Will just work to get fuel level below the overflow and see how it runs, keep an eye on the plug. Only thing I can think to do. Thanks again for your input.
 

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Manual says float top should be 14.7mm above float chamber mating surface when inverted. Mine was at least 5mm below that, and I could not get it to that by bending the tang.

As the manual also says fuel level should be 2-3mm above float chamber mating surface when upright and level, I opted for that method. I put a clear tube on the drain and have been working trial and error to get it to that.

Problem is that even with fuel level as much as 10mm below the mating surface, I'm still getting a continual drip from the overflow.

Any ideas or suggestions will be appreciated.
best way (I find) to ensure your float is correctly adjusted (based on your atv's specs).
Plug a clear hose in the drain tip and you will clearly visually see the level of fuel in your carb's float setting.
Just a FYI. .before you try finding issues that may not be the culprits :)

Automotive tire Motor vehicle Automotive lighting Steering wheel Alloy wheel
 

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Discussion Starter · #5 ·
Thanks for your input. You might not have seen it, but I mentioned doing that in the top post. However, I found it inconsistent.

If, after the first trial, I closed the drain and tipped the tube down to drain it, then tipped it back up and repeated the procedure, I'd get a progressively higher fuel level at least the next two repetitions. In addition, though the fuel level remained at or below spec in the tube, I would still sometimes get a steady dripping from the overflow port.

Have the carb back in, w/ a clear tube on the overflow port bent up so I can track it. When I first open the fuel line with engine off, it comes up to the level of the interior drain port, but if I start and run it, tip the tube down to drain it and raise it back up, I then only get about a half inch into tube while running.

Only thing I can come up with is the float needle not sealing unless it has the vibration of the running vehicle to seat it, even though it looks to be in good condition. I've ordered a rebuild kit and will replace it.
 

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Thanks for your input. You might not have seen it, but I mentioned doing that in the top post. However, I found it inconsistent.

If, after the first trial, I closed the drain and tipped the tube down to drain it, then tipped it back up and repeated the procedure, I'd get a progressively higher fuel level at least the next two repetitions. In addition, though the fuel level remained at or below spec in the tube, I would still sometimes get a steady dripping from the overflow port.

Have the carb back in, w/ a clear tube on the overflow port bent up so I can track it. When I first open the fuel line with engine off, it comes up to the level of the interior drain port, but if I start and run it, tip the tube down to drain it and raise it back up, I then only get about a half inch into tube while running.

Only thing I can come up with is the float needle not sealing unless it has the vibration of the running vehicle to seat it, even though it looks to be in good condition. I've ordered a rebuild kit and will replace it.
Yeah a new rebuild kit never hurts for sure.
But just a comment .. maybe I misread your reply.. but seems when running the fuel level is never consistent anyways.. depending on the fuel consumption at the time.So I never check while running, only for setting as specs.
Last little quote... last carburator issue I had, the screw tip was used and was always dripping.
BUT SEEMS like its the float needle.. I agree
 

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Discussion Starter · #8 ·
But thank you for your comment, as it made me think as to why I'd get different readings w/ the fuel level rising each time, then no longer. Only thing that makes sense is air pressure in the float chamber. I believe it has a breather to it, but maybe it's partially clogged. The longer the carb sits w/ fuel to it, the interior air pressure slowly reduces, so the fuel level comes up until it gets to the true level and stays there. I'll check that when I replace the float needle.
 

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I didn't check it while running. I was checking it w/ the carb mounted on a bench, and got three different fuel levels when retesting w/ the clear tube method.
So sorry.. french acadian here haha
Understand now, and not normal
You should always get same readings in my opinion (and my test)
Just dumb quote.. ensure you have clean fuel distribution on your bench for testing
Cause if you are using your tank.. unsure if you are or not.. I had issues with the filter screens , both busted up on mine in in my tank (full fuel and reserve) .. attached to the pet cock valve

But again, nothing to do with oververflowing of your fuel, simply quoted for incossistent results with your carb valve testing

Hope you succeed , let me know if you don't mind as I like undertanding the solutions for odd issues.
Take care
 

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Discussion Starter · #10 ·
No worries. And yes, I would have expected consistent readings. Can't remember why I ended up checking it in repetition. I think maybe the tube got loose and tipped down and when I replaced it I noticed that the level was different. But it turns out to be a good thing, because I'll track down the port to the carb breather and make sure it's completely clear.
 

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Hopefully not to late with this but when you change out the "O" ring for the needle, some have a flat side and a ribbed side on the back. If it's not put in the right way, it may still leak. Ask me, I cursed a blue streak many times until a small engine shop told me about it when I changed the "O" ring on my ice auger motor. Flipped it over, no more leaks.
 

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Discussion Starter · #12 ·
Thank you. I just used one I had on hand, standard round, seemed to seal very well but maybe I was mistaken. Will be replacing it when I get the kit, but I'll pay closer attention, and make sure to verify more carefully.
 

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Discussion Starter · #14 ·
Thank you. The one I removed was the typical round o-ring and that's what I replaced it with. Will get a new one with the kit I ordered, but I don't think the o-ring is the problem. I think it's the float needle.
 
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