Frequency of oil & filter changes, etc

[Ryan Wright]

What do you all recommend for oil & filter changes on the 8V92?

My generator manual (Yanmar/Kohler 12.5kw) says oil & filter every 150
hours, air & fuel filters at 300 hours, so I'm following that for him.
However, I don't see recommendations for the 8V. I changed everything
on it 1000 miles ago, so in terms of miles I'm OK, but time wise - I
changed it last summer shortly after I bought the coach. I doubt I'll
put more than 2000 - 3000 miles a year on the thing in the near term.

Also, when should the engine air filter be cleaned & what's the
procedure on that? I'm particular about maintenance and just want to
make sure I keep up with the details.

Thanks!

-Ryan
'86 PT-40 8V92