Onan gensets have a low-oil detection system, when oil level is low it will not start again until oil level is full. I'd sure change the generator motor oil N filter + fuel filter just as soon as it started unless the previous owner has records to prove it has been serviced lately.
Take along spare drive engine fuel filters going to AK., parts for a DP are kinda hard to find, and everything in AK must be flown-in from Seattle if you have an emergency/breakdown.
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2000 Winnebago Ultimate Freedom USQ40JD
, ISC 8.3 Cummins 350, Spartan MM Chassis. USA IN 1SG 11B5MX,Infantry retired;GS Life member,FMCA
" My fellow Americans, ask not what your country can do for you, ask what you can do for your country. John F. Kennedy