A spec KY means it is probably in an older RV (like mine). The rubber fuel line to the main tank may be cracked. There is never gonna be one magic bullet to fix your generator. Use search, and find lots of posts regarding Onans. One of these has links to the factory manuals and troubleshooting processes.
Originally Posted by speedy g
I have an onan 4000 ky it has spark, fuel and compression yet it won't start what could be wrong any help would be appreciated
George Schweikle Lexington, KY
2005 Safari Trek 28 RB2 Workhorse 8.1, FMCA 190830, Safari International chapter. 1999 Safari Trek 2830, 1995 Safari Trek 2430, 1983 Winnebago Chieftain, 1976 Midas Mini