Yamaha 50hp Outboard Maintenance

Purchase

  • Oil filter
  • Spark plugs
  • O-ring gaskets for oil and gear case plugs
  • Marine Engine Oil – SAE 10W-30 for 4-stroke
  • Gearcase lubricant – SAE 90W
  • All purpose marine grease

Tools

  • Paper towels
  • Disposable gloves
  • 14mm socket (oil drain)
  • 18mm socket (spark plugs)
  • Socket wrench + extender
  • Large flat head screwdriver (gear case drain screws)
  • Oil filter wrench
  • Gearcase lubricant pump (with aluminum adapter)
  • Pliers
  • Small piece of 2×4 lumber
  • Oil drain pan + box to stand it on
  • Flattened cardboard box (lay underneath motor to catch any spills)
  • Metal file

Propeller

  • Remove pin and remove bolt then propeller
  • File minor dings
  • Some people online suggested following for stuck props, but I’ve never had an issue: 
    • Torch to help free a stuck prop
    • Chisel to free frozen sleeve
  • Grease and reassemble prop