some good advice from the group as always i too am a newbie to motor homes and bought a vintage unit the one thing i haven't seen anyone mention is to pull the carb once you get the spark issue fixed and clean the carb out, my generator had set about 8 years it is a honda but same principal it had only 32 hours on it when the pickup in the fuel tank failed then came the setting part the original owner wasn't mechanical at all.
took it apart cleaned it with carb cleaner and replaced the needle,seat is made in on this one, and gaskets has worked well ever since.
i bought my parts on line at a place called boats.net a little slow to ship but better then our local Honda dealer probably have onan parts too.
good luck with your project.
happy rving frank,cricket and harley