Originally Posted by Maui
Thanks for the advice Avanti and Robert you hit the nail on the head. I charged the house battery on my old 1994 Dodge Leisure Travel, using shore power and it started right up. It does surge in rpm a lot... not sure what that is about. It ran for about half hour then for about 15 min after I turned on the A/C putting a load on it. Surges and on one low rpm surge it couldn't make it back and quit.
Great trick on starting the Van first when house battery is low. I'll try that next time.
When was the fuel filter changed last? If you have the original manual or download the manual on the Onan website - which is for the newer model and not all applies - there is a troubleshooting section. One thing the manual says when there is surging is to change the fuel filter. Other things is says to check are the spark plug and the air filter.
Also you may have put the load of the A/C on too soon.
If you can get it running even without a load so that it keeps running, put a couple of cans of Seafoam in the van gas tank and let that run through the Onan (amount depends on the size of the van gas tank and how much gas is in it). It may clear the gunk - if any out.