carb leak problem here too

[oldschool73]

I bought the quad with the carb leaking, Had the carb cleaned and rebuilt but it still leaks every now and then out the bowl overflow tube. the mechanic who fixed the carb said he found some really fine sand in the bowl and suspects it wore out the bore that the needle moves up and down in. Also the tip of the needle was torn so it was replaced in the rebuild as well as jets and gaskets. He said these carbs don't have a replaceable seat for the needle is this true? Anyone else have this problem? is there a fix? it runs fine but when it starts to leak I can tap on the side of the bowl and it will stop. It is annoying he suggested I buy a different carb for it. it is an 03 400ex with almost no hours on it. Also what is the difference between a 2005-2006 carb and a 1999-2004 carb? Will a 2005-2006 carb bolt right in?

[EXriderO2]

i had the same problem and i took it apart and i had gas in my float so i replaced the cacked float and it fixed it. well i ended up doing a whole rebuild about 190 fix. but then i looked on ebay and found carbs on there that are brand new for about 50 bucks so just get a new carb save money and use the one u got for parts