110 cc quadbike fuel leak

[tj2010]

hey guys my name is troy my mates call me tj how are u i am new and just looking for a bit of info i have a 110 cc quad i bought it off my cousin rode it for a while and discovered it had a fuel leak it was coming out of the carby in to the pod filter and coming out of the very bottom hose that hangs down near ya foot rests so i changed the carby thinking that would fix it but it didnt so i am hoping to get some info on what may be happening it seams to me to be getting to much fuelit doesnt have a fuel filter or fuel shut off valve it just has the pipe off the fuel tank streight in to the carby any help is much appreciated thanks tj

 

[bulldog93]

Float needle could've bent thus changine the float height and then pouring out of the overflow drain:
- http://www.miniriders.com.au/ask-tech-masters/25238-fake-mikuni-air-fuel-screw-2.html

To make tuning those oval bore Fakuni's easier you could temporarily fit a 360 degree carb spacer between the manifold and the head ... A cheaper idea would be to buy another manifold , cut right thru it on the straight part near the carb mount flange , clean the edges up with a file , then fit a piece of rubber radiator hose and 2 hose clamps so that you can turn the carb to the side ...

Some carb tuning info ...

1) Float Height :

The float height controls the fuel level in the float bowl , which can also effect carburetor performance . Set float height according to specification before any other tuning . The float height may need to be adjusted for best performance on different track types .

2) Idle / low speed :

Tuning of the engine at idle and low speeds is accomplished by adjusting the Idle Mixture Screw or changing the size of the Pilot Jet (also called Slow Jet) . The Idle Mixture Screw is a fuel adjustment when it's on the intake manifold side of the slide , so closing the screw or turning it clockwise will lean the fuel mixture , and opening the screw or turning it counter clockwise will richen the fuel mixture .

If the Mixture screw is on the air filter side of the slide it's an air screw , turning it in reduces the amount of air and richens the mixture and turning it out leans the mixture out .

To adjust the Idle Mixture Screw proceed as follows . Turn the Idle Mixture screw in until it lightly seats or stops . Back the screw out the specified number of turns . Warm the engine and set the Idle Speed screw slightly higher than the desired idle rpm . Turn the Idle Mixture screw in or out to obtain the highest rpm . Turn the Idle Speed screw to the desired idle rpm . A slightly rich idle mixture is usually better for acceleration .

If a smooth idle cannot be obtained with the Idle Mixture screw between 1/4 - 2 turns out from closed , a different size Pilot Jet may be needed . The proper size Pilot Jet will allow for smooth acceleration from an idle and steady engine speed up to 1/4 throttle opening .

3) Midrange / Part Throttle :

The Jet Needle primarily controls fuel flow between 1/4 and 3/4 throttle opening . The Jet Needle has five notches and a C-clip on the top of it . To richen the part throttle operation , move the clip to the next lower notch . This will hold the needle farther out of the nozzle . To lean the part throttle operation , move the clip to the next higher position . The highest notch (farthest from the narrow tip) is considered to be the 1st position.

4) High speed / full Throttle :

The Main Jet controls the fuel flow at throttle positions of 1/2 to full throttle . The jet size or diameter in millimeters is stamped on the jet . Altitude and weather conditions can effect the engine operation enough to require changing the size of the Main Jet . High air temperature , humidity , or altitude could require a smaller Main Jet . Low temperature , humidity , or altitude would require a larger diameter Main Jet . Running the engine with an improper Main Jet could result in a loss of power , high engine temperatures , or engine damage.

- http://www.miniriders.com.au/tech-talk/18676-wr426-problems.html

All you really need to know is that the little rod the holds the floats into place might be bent chaging the height of the floats. Just push it out and adjust it.

That's my guess though. Good luck with it .

 

[tj2010]

Thanks mate will give it a go