How To Change Oil Filter On Onan 4000 Generator. I just bought a new to me motorhome with an Onan 4000 generator. B series 122-0645 N series 122-0323.

Once the oil is out put a little sealant on the plug and screw it back inJust do not over tighten it. Run the generator for a few minutes to warm it up before you drain the oil. Step-by-step oil change procedure Run the generator for a few minutes to warm it up before you drain the oil.
To took it to Rv repair shop and ask them to change it.
Run the generator for a few minutes to warm it up before you drain the oil. Under the generator is a small yellowish cover. Just got a call it will. After they did much checking I was informed mine did not have a oil filter.

