View Full Version : wont start from gravity fed tank. help please

03-31-2010, 8:46 PM
so my xj650 maxim ran fine when I parked it about a month ago to start changing the tank out. i swapped the stocker for a sportster gravity fed tank. I plugged the vacuum hose tight, hooked up the fuel line to the new petcock and now nothing. It just cranks and cranks with not even a spit or sputter. it seems like it should be getting plenty of fuel, is there any way to check? im unfamiliar with the whole 4 carb setup

i know others have did this so what am I doing wrong?

03-31-2010, 10:02 PM
what are your vacum ports looking like on the carbs?? chances are you need to plug those OR run a line from the petcock to the carbs. what type of carbs are they....kehin, mikuni

03-31-2010, 11:29 PM
i have them all plugged. not sure what brand they are, just the stock Yamaha carbs

04-01-2010, 5:46 AM
Simple answer may be did you have a vented gas cap before? And now when you changed out the tank also put on a non-vented cap? Take the gas cap off and see if that changes anything.