Mid Missouri here. We inherited a 2002 Coachmen class C 29' long.

[Qingeaton]

I can't seem to find anything specific to this RV as far as the plumbing system, and particularly, the winterizing of it. The pump doesn't seem to draw from the port.
Every one of these seems a little different, and I've watched 20 videos and I still can't figure this out. I've done all sorts of replacements and fixes so far, with the fridge, power converter, etc, so I'm not a total newbie at stuff. Only have 1 month to get it done too.

 

[AbdRahim]

Welcome

 

[Fish]

I don't know anything about your motorhome but I've had 2 motorhomes, several travel trailers and a fifth wheel and the only way I've ever winterized is with air. This Monaco I've got now may not work that way but I don't plan on it ever seeing frigid weather.
I drain the water heater first. Drain the fresh water tank. Hook up a piece of garden hose with an air coupling I put together to the city water inlet.
Blow air in not exceeding 50 pounds with my air compressor opening one faucet at a time, then a do it a few more times.
Pour rv antifreeze down all the drains so it's in the traps. Pour it in the toilet also.

 

[Qingeaton]

Thanks for your reply. I did blow out with air at 30 psi from the city water hook up, did empty the hot water tank, there are just a few runs of waterline that go to the tank, or back from it and they still have water in them. Today I will be just removing the line from the intake side of the pump and running the pink stuff in that way. Would be better if I could understand the whole layout with a flow chart of some kind. The owner's manual is a joke. It did come with a vhs tape, so if I could find an old player somewhere...lol.