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cv carb overflowing non stop

9roadking8

New Member
Can some one please help me ???? I rebuilt my cv carb because it was leaking gas out the overflow it would keep running through the carb until I shut it off at the petcock, well i rebuilt it and it does the exact same thing, the carb was 2 months old when taken off with very little miles, but it sat on my shelf for close to 3 yrs, did everything ruin because of this ? the carb works but the gas keeps flowing.Please help, ive taken the carb apart so many times and i replaced everything in the kit and still same results
 
Welcome to the forum roadking, when you had it apart did you blow out the fuel intake passage where the float needle stops the fuel flow? Sometimes something can sit hidden up inside the passage untill fuel flows into it. Also did you check the float setting? Some year cv carbs also had a recall on the float needle.
 
If you can keep the bottom cup OFF... Can you stop the gas flow manually? by lightly pushing UP on the float?

I don't know if you have a vacuum petcock ,,,, You may have to apply a LITTLE suction tube on suction tube side of valve and draw a suction on it to open the gas valve (petcocks)....

I know how frustrating it is for you..

OR MAYBE just try to give the FLOAT a LOWER gas setting.... closing the needle EARLY for LESS gas in bowl....If it quits running by the needle.........

I always replaced my PHILLIPS head screws at hardware store for allen heads AS i can remove them easily without removing carb each time... Allen heads are easier to get screws into place.. REMEMBER not to OVER TIGHTEN.... and make sure (excelerator pump) squirt pump plunger and rubber are back in right...

signed....BUBBIE
 
If it happens to you, and you have not service bike in a long time do shut the fuel petcock OFF, quickly grab a large screwdriver, hold the shaft and bang the float bowl with the handle ''eh" robustly or if you have a rubber or plastic mallet just do it. It may jar the needle closed long enough to get the fuel tank drained and get access to the float bowl drain, and carb serviced. Happens if bike is allowed to sit for awhile with bad gas in the carb...not that that would happen to this ol' dog...LOL!

As for verifying float level, do make sure that when the carb was apart, that the seat/valve/float travel is "free" and the service manual only shows the "dry" angle method, not what is called "float drop" and seated heght. So when assembled, you can verify float level "wet" by using a clear tube bent in a "J" inserted into the float drain hole and gas should be up to proper level without overflow. THEN bolt in into your bike (you can check it again once installed).
 
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If it happens to you, shut the fuel petcock OFF, quickly grab a large screwdriver, hold the shaft and bang the float bowl with the handle ''eh" robustly or if you have a rubber or plastic mallet just do it. It may jar the needle closed long enough to get the fuel tank drained and get access to the float bowl drain, and carb serviced. Happens if bike is allowed to sit for awhile with bad gas in the carb...not that that would happen to this ol' dog...LOL!


NEWHD74FAN.

MAN,, YOU AND ARNOLD........LARGE SCREWDRIVER and WACK it.....

I guess that has worked for me more than a couple of times...I CRING to think about wacking and MISSING....... I try NOW to never let my bikes sit long enough for the CRUD to happen OR GROW.....SEA FOAM needed on my sporty TOMORROW as the big bike is licensed and I am able to ride it.. 65* today here in west wash.. a MILLION bikes out... rain tomorrow nite... but what a warm winter. EL-NINO, all OUR water seams to go to you in calif..

The stuff they call FUEL today...
I used to bypass your state in the motor home/bike because of the either in the gas in calif. GTBE? i think it was, We used to have it up here in WA. for a while but THANKFULLY IT GOT taken out...
I listened to DR Wattenberg on KGO AM radio(calif.) complaining to governor Brown to get it out..IT was poisoning the ground water.. That was a while ago...

I can still smell it a little today around the OLD service stations when i go thru calif....
Is that stuff still being used or have they caught on?

Enough for now... THANK YOU NEWHD74FAN YOU always have GOOD answers, and IT is ALWAYS FUN to read your post.... hope you didn't mind me joking with you......

signed....BUBBIE

OH, YES, the POINT of MY POST was "SEA FOAM"
 
Bubbie, point well taken...those days of allowing a bike sit for more than a couple months stopped 3 or 4 bikes ago...! Figure I am too old to be doing things the hard way. Have use Berrymans' Chemtool/Gumout since the late 80's, with similar results to Sea Foam to keep carbs varnish & gum free. No more screwdriver handles or plastic mallets for me...living in SoCal means year round riding, not nearly as seasonal as Northern California. :D

The gas additive MTBE formulated by the oil companies to lower emissions and gas used (read "filler"). All I know is we used to have a 1991 Honda that got close to 40 mpg. Once they started using seasonal "reformulated" gas, never could get over 30 mpg...do the math...how can gas consumption mileage loss of 20-25% mean less polution, don't care how much the oil companies or tree huggers tell us how great the gas is. :(
 
The float height could be wrong setting the correct float height is fully coverd in the sevice manual
the float could be punctured and sinking rather than floating
the needle valve could be failing to seal could be dirt in the seat or on the tip of the needle, as the float needles have a rubber coating the rubber part can go hard and fail to seal - replace float needle

Brian
 
Thanks for all the tips, ill try adjusting my float and also try to check my float needle,can some one tell me what the proper way to adjust the float bowl? ill let you's know what happened after ive tried these things again thanks for all the great tips, and this site is awesome
 
9roadking8, don't forget Brians' suggestion about the float having microscopic hole, test by having float out and shaking it, no noise? then submerge in gas or solvent (you will see a string of bubbles come out if it has a leak). Those floats are made veerryy thin, especially at seams/bends.
 
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