Mercury - 300 Hour Maintenance Kit (No Anodes) Verado L6 Series OEM Service Components 8M0149427. Overview. There's a certain peace that comes from knowing your engine is cared for the same way Mercury intended. When you're running a big Verado, you don't want shortcuts or guesswork-you want parts that keep the engine smooth, predictable and ready for whatever the day brings. The Mercury 300 Hour Maintenance Kit 8M0149427 delivers that confidence. It gathers every essential service item you need