Honda BF35A-BF45A Outboard Motors Shop Manual., Page 254Get this manual
3MAINTENANCE ASSEMBLY
BF40Ae50A
2ACCELERATION DEVICEDIAPHRAGM
1ENGINE OIL
INSPECTION
Used engine oil may cause skin cancer if repeatedly left contact with the prolonged periodsAlthough this is unlikely unless you handle used oil on daily basis, it is still advisable thoroughly wash your hands with soap and water as soon as possible after handling used oilKEEP OUT OF REACH OF CHILDREN1) Place the outboard motor in the vertical position2) Remove the engine cover3) Remove the oil dipstick and wipe it clean4) Insert it all the way down the dipstick hole, then pull it out and read the oil level5) If the oil level is low, add the necessary recommended engine oil to bring the oil level to the upper mark on the dipstickDo not overfill11I UPPER LEVEL
11 LOWER
DIPSTICK