Do you know what kind of MH and what kind of generator? That info would be a big help in helping you. Generators are usually rated in watts or Kw, not amps in an RV.
2003 Newmar Mountain Aire, Workhorse W22, 2008 Saturn Vue, Falcon 5250, & US Gear Unified Tow Brake
The motorhome is a 1994 Allegro Bay Diesel Pusher with a Propane generator. I think it is an Onan but I'll have to check on that and post it later on today.
When you get the model # also get any other numbers you might find. The Onan website will give you good pictures of where everything is located on your specificmodel. Typically you will find the comparable model will be downrated about 10% for propane over gasoline. What would be a 4000 watt on gas will be 3600 on propane.