Mercury - 300 Hour Maintenance Kit for 5.7L V10 Verado & SeaPro Scheduled Service Package OEM Marine Components 8M0207808. Overview. Every boater knows the feeling - that deep breath of confidence when your engine fires up smoothly after a long week, waiting patiently for the next run offshore. That trust doesn't just happen. It comes from taking care of your equipment the right way, with parts you know won't let you down when the water turns rough or the wind picks up. The Mercury 300 Hour Main