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Mercury | 300 Hour Service Kit | V8 4.6L FourStroke | 8M0149931

The Mercury V8 (4.6L) FourStroke 300 Hour Service Kit – 8M0149931 provides the essential components required to perform the recommended 300-hour maintenance on Mercury 4.6L V8 FourStroke outboards. This complete maintenance kit includes the necessary engine oil, gear lube, filters, ignition components, and cooling system parts needed to keep your Mercury outboard performing reliably.

Completing the 300-hour service helps maintain proper lubrication, cooling efficiency, and ignition performance. By packaging the required service components together, this kit simplifies scheduled maintenance and helps ensure your Mercury V8 FourStroke continues operating at peak performance.

What’s Included in This Kit

• 1 x Gallon 25W-40 Marine Engine Oil
• 3 x Quarts 25W-40 Marine Engine Oil
• 1 x Quart Mercury High Performance Gear Lube
• 1 x Oil Filter
• 1 x Fuel Filter
• 2 x Gearcase Drain Seals
• 1 x Thermostat
• Spark Plugs
• 1 x Alternator Belt
• 1 x Water Pump Repair Kit
• Anodes

Benefits of the 300 Hour Service

• Maintain proper lubrication with Mercury 25W-40 marine engine oil.
• Protect internal engine components with a replacement oil filter.
• Support reliable fuel delivery with a new fuel filter.
• Maintain cooling system efficiency with a thermostat and water pump repair kit.
• Ensure proper ignition performance with replacement spark plugs.
• Maintain charging system reliability with a new alternator belt.
• Protect against corrosion with replacement anodes.

Engine Compatibility

• Mercury V8 FourStroke Outboards – 4.6L

Always verify your Mercury outboard model and serial number before ordering to ensure compatibility with your engine.

• Engine Application
  • 300 HP 4.6L V8 - 2B529482 & Up
  • 225 HP 4.6L V8 SeaPro - 2B529482 & Up
  • 250 HP 4.6L V8 SeaPro - 2B529482 & Up
  • 250 HP 4.6L V8 - 2B529482 & Up
  • 300 HP 4.6L V8 SeaPro - 2B529482 & Up
  • 200 HP 4.6L V8 Pro XS - 2B529482 & Up
  • 225 HP 4.6L V8 Pro XS - 2B529482 & Up
  • 205 HP 4.6L V8 Pro XS - 2B529482 & Up
  • 300 HP 4.6L V8 Pro XS - 2B529482 & Up