suzuki dt65 1990 carb over-flowing

[zem]

hi all, i have a dt65 on a 1990 and my bottom carb keeps overflowing up through the main jet from the float chamber? i have had it apart numerous times, the float when pushed up by hand works fine and shuts the fuel off, when i turn it upside down the fuel shuts off fine but as soon as i re-assemble it leaks through again. i have changed the float and the needle valve from another carb that works fine but again as soon as i re-build i have the same prob, when its apart and i put fuel pressure in there and hold the float up it stops the fuel fine, but re-build and the prob returns, if i shake the carb i can hear the float moving about so i know it isnt wedged or anything, there is no hole in the float or hairline cracks in the carb i am lost does anyone have any ideas????
thanks

 

[waffles1]

Re: suzuki dt65 1990 carb over-flowing

Take the float out and hold it under water and see if there are air bubbles or if it is filling with water. I know you said you didn't see any cracks or holes but that sure sounds like your problem. If you see no problems try switching the float to another carb and see if the problem follows the float. You'll have to ask someone smarter then me if this could be a fuel pump issue. Is this occurring while the motor is running? If it happens while you are priming I believe on this model that is normal. If you over prime gas will come out an overflow hole on the top/back of the carb. Good Luck.

 

[99yam40]

Re: suzuki dt65 1990 carb over-flowing

Did you try a different seat along with the needle and float. make sure you clean everything up real good when you pull the seat out to make sure there is nothing getting into needle and seat when fuel is flowing
Did you check and set the float level to specs

 

[rpauti]

Re: suzuki dt65 1990 carb over-flowing

WITH THE CARB OFF THE ENGINE, REMOVE THE BOWL. PUT A PEICE OF FULL LINE ONTHE FUEL INLET BLOW THROUGH HOSE AND AIR SHOULD PASS WITH FLOAT DOWN; WHILE BLOWING (GENTLY) RAISE THE FLOAT AND YOU SHOLUD BE ABLE TO BUILD PRESSURE AGAINST THE NEEDLE AND SEAT. iF NOT, REMOVE THE FLOAT AND NEEDLE AND CLEAN SEAT WITH CARB CLEANER AND A Q- TIP. THEN RECHECK.

 

[Silvertip]

Re: suzuki dt65 1990 carb over-flowing

And the float will not work properly if it is not adjusted properly. If you have pushed on it with any force at all you have probably done what amounts to RAISING the float level. So even though it shuts off manually, the fuel level rises too high when the float is actually floating. Set the float properly and try again.

 

[magnumrapala]

Re: suzuki dt65 1990 carb over-flowing

ive seen similar things with paper in-line filters, the fuel eats the glue and sends it in to the carbs and will not allow the float to close