class c onan 4000 gen

[mskog13]

i have a 2000 minnie with an onan 4000 generator. i can start the generator (without the cab on), put a load on it (or no load), and it will run fine for about 25 mins., and then it seems to starve for fuel and then shut down. now if i run the generator and it gets to the point where it starts to surge, and i turn the cab motor on, the generator will level out and continue to run with no problems. any suggestions as to why the gen. won't stay running, unless the cab motor is running?
the carb. was replaced 6 months ago with a new one at camping world

[genesimmons]

maybe the gas cap bad? or some other type of gas tank vent maybe?. try it next time with gas cap loose and see what happens. could be the fuel filter for the genset

[mskog13]

tried it with the gas cap loose, no change. will continue to look for any other vent leaks. fuel filter was changed with the generator service