2000 Yamaha YFM400FWA(M) Factory Service workshop Manual, Page 80Get this manual
ENGINE OIL REPLACEMENT
INSP ADJ
4.Remove: Engine oil filler plug (dipstick) Engine oil drain bolt Drain the crankcase of its oil
5.If the oil filter cartridge is also to be replaced, perform the following procedure
Replacement steps: Remove the oil filter cartridge with an oil filter wrench 2Oil filter wrench: PNYU-38411, 90890-01426
Lubricate
the O-ring of the new oil filter cartridge with thin coat of engine oil