1990 Winnebago Warrior Kohler generator

changed spark plug, added oil, gassed up and no firing after many times turning it over. Is there some sort of reset?

Based on what you did already I would remove the spark plug and check for spark, no spark ohm out coil. Your Koehler may have points, check gap and also check gap from the coil to the magneto with a match book cover. If you have spark remove hose going to carb an crank genset, does gas squirt out? If not remove line from fuel pump intake that comes from your main gas tank and connect a piece of hose there to. draw from a gallon gas can. If you try these simple things and post back you will be able to narrow down your problem.

Sounds strange but some times to get my generator to start I have to have the RV running

Well, I still need to find that reset button. It's in the PDF version of the manual but the photo is too poor to actually use it for help. But apparently that reset must be done if the generator stops working due to a low oil level, which mine had.

Well, the oil and gas weren't a fix. I need to manually reset the oil level switch. The PDF manual I downloaded states this and also has a completely unreadable photo of the switch location. I cannot find the switch and have no idea where it is. Any help out there?

Many thanks

Well I tried everything that I can do diagnostically. I finally took the RV to a service shop. The tech is just amazed at how inaccessible the gen-set is and that simple things are just not able to be gotten to without pulling the entire unit. Now that is frustrating. I can see the fuel pump but can't get to it and that may be the problem as there is no fuel odor even when choked. I'd install a new one if I could access it. Pulling the set looks almost as impossible. I have the installation manual but even getting to anchor bolts/nuts is ridiculous. The tech said a minimum of $500 but if he could at least access the fuel line he could determine fuel supply but even he can't! What a ridiculous set up.
So I think I'll keep an eye out for a stand alone generator that I can just set off and plug into if I need to. I rarely need the gen. so even not having one isn't the end of the world. I have an inverter and solar charger so maybe that will be enough for my simple needs.
Thanks for all the input!