Generator Questions 2008 Itasca Cambria

[Rowbear08]

Itasca Cambria '08
Will the generator start up without house batteries from the engine battery and should I try starting it up while the engine is running ?
Our rig has been sitting in storage (outside since '20). Occasionally we would start the generator as well as the engine during that time but the last time we were able to start the generator was spring of '23... it ran for awhile and then stopped on its own. The house batteries we took in for testing and they were kaput....haven't replaced them as yet. We did read that once the fuel tank reached about 1/4 full there was a safety shut off to the generator. I have added some gas via a jerry can and am going to add some more but am not sure if I will be able to start it.
Thanks in advance for any advice.

[powercat_ras]

The fuel pickup for the generator is aproximately at the 1/4 tank level so if tank can not be run empty from the generator stranding someone with no fuel to drive away with.

If it stops on its own it may store a fault blink code telling you why. You press the STOP/PRIME button once to see the blink code. The codes are described in section 6 of the ONAN manual.

The generator starter cable is off the house battery circuit in your unit.

You might be able to hold down the battery boost switch on the dash and tie the chassis and coach battery circuits together with the coach engine running and get enough power to crank and start the generator, even with the coach batteries weak or totally removed. The starter can try to draw over 200 amps so this may or may not work depending on the condition of your chassis battery and your chassis alternator.

[Morich]

Ever try to start a car with a totally flat battery like after leaving the lights on overnight? Somewhat the same with the RV except you don't need to get out the jumper cables in lots of cases.
If you have even a really flat battery in the coach but can start the RV engine, the engine running operates a solenoid to connect coach and chassis batteries together and that means the engine alternator is also pumping power to both sets.
It may help to rev the engine a bit like you might have done on cars? When spinning faster it puts out a bit higher voltage and that will likely be enough to crank the generator.
One thing to know is if it ran out of gas, it may take a longer cranking to first get gas to the generator and then fire.
It's a good idea not to crank steady for more than a minute and then let the starter rest and cool before trying more. Just not doing it enough to get it too hot?

But when any doubt for any reason whether the generator will start, it is always better to have the engine running first as that gives the best power from all the systems without fear of running any battery down!

[Rowbear08]

Thank you for the help.

[Rowbear08]

Thank you for the kind help.