There has been some confusion ( at least to me) from posts below if a 20 hour service was required
and can you do your own maintenance. The email should help understand.
Good morning Mr. XXXXXX,
Thank you for your e-mail regarding your Mercury engine, serial #2B544452. We appreciate the opportunity to respond to your concerns.
The first required service for your new engine would be at 100 hours or once yearly whichever comes first. If you decide to do your own maintenance we would like you to keep a service log of the date, hours on engine, services done and products used. IN your Owner's Manual there will be a maintenance schedule list for you. The 20 hour service is a recommended service but not required and will not void your warranty in any way.
We hope this information is helpful to you. Should you have any further questions or concerns, please contact our Customer Service department at 920-929-5040 between the hours of 7:30 am and 4:30 pm, Monday through Friday, CST.
Sincerely,
Mercury Outboard Customer Assistance
Ref.# 2018-50656