2001 F115 500 hrs. service

[Dreamcatcher]

I'm a first time Yamaha engine owner, have just bought a boat with twin 2001 F115Z and FL115Z with 500 hrs. hours on meter. Can someone tell me what those engine numbers mean ?
I have been told the engines have not been serviced for approx 2 years. Can someone advise as to what service I should do ? Best place for parts, diagrams, etc.
Thanks in advance,
John

[boats.net]

They are due for the 400 hour service and water pump replacement. The 400 hour service is listed in detail in service manual and brief description in owners manual. Can go to www.yamaha-motors.com for manuals. You can see parts breakdown and order parts here on boats.net site, the link is at top of page.