400 Ex Blowing Gas Out Carb

[GYOGI65]

400 EX fresh rebuild 426cc stage 1 hot cam ,11:1 wiesco piston
42 piliot jet new top end
when started today after installing new head started first crank then started to skip blow black smoke and blow gas out intake now need to run at least 3/4 throttle to start but shut of gas and smooths right out just before it quits
i know this sounds like float or float valve but could it be the air cut off valve or somthing with this type of carb looking for any ideas before i order more parts and they dont cure the problem

[2004exrider]

Did you drain the carb before rebuilding it, you might have forgotten to turn the drain screw back in and its just leaking like crazy. Or when you put the pilot jet in, a little bit of dirt got in the carb and is clogging the needle for the float.

Jimmy

[JW450R1]

did u jet it when doing the motor work?.something sounds like it may be in the carb for the problem.

[jordan_m6]

Originally posted by JW450R1
did u jet it when doing the motor work?.something sounds like it may be in the carb for the problem.

not to be a prick but he knows it is the carb.

just clean the whole carb. i cleaned mine about 3 months ago and i couldnt believe the crap that came out.

[plkmonster2]

Make sure your timing is still right, AFTER you check and recheck the carb. This is a more tedious process. If the tensioner wasn't snapped back, it could have skipped.

[GYOGI65]

THE GUY THAT MACHINE WAS bought off must have taken jets out or changed them back to a diffrent size and lost the brass insert that goes above jet holder into bore .borrowed piece from another carb reassembled hit the key runs like a watch this has been a five month project and if not for this forum would have called it quits long time ago.THANKS EVERY ONE YOU HAVE BEEN A GREAT HELP. JUST hope that some one doesnt jet a machie and lose this piece honda pn#16012-hn-003