I have a1997 Fleetwood Flair with a Onan 4000, has worked great till trying to use it labor day weekend. just wouldn't start. gas tank on the rv is full, tried both the inside and outside start switch. checked the 5amp fuse, its ok. Pulled the air cover and filter and poured a little gas in, it would fire for a second then die.? I must admit last year and up till now we hadn't needed it, so I am thinking the gas has turned bad in the Nikki Carb. I pulled the carb but I am not sure how to get the bowl off. Does it unscrew? Or am I looking in the wrong place for the problem? I also pulled the spark plug, it was dry, also had good spark. Thanks for any and all help, I just found this forum / web sight and this is great!!! cman.