Mercury 300 HP V8 4-Stroke 2019–2023 Service Repair Manual – PDF Download

🛠️ Mercury 300 HP V8 4-Stroke 2019–2023 Service Repair Manual – PDF Download

🧰 OEM Factory Workshop Manual – Covers Mercury 300 HP V8 FourStroke CMS Outboards (Serial No. 2B529482 and up)
📲 Instant PDF Download – Works with Windows, macOS, iOS, Android, and Linux
🔧 Used by Mercury-certified technicians, marine dealers, and serious repair professionals

🔍 Model Background

The Mercury 300 HP V8 Four Stroke outboard (2019–2023) was part of Mercury’s next-generation naturally aspirated outboard lineup, introduced to replace the aging supercharged inline-6 Verado models. Built on a robust 4.6L V8 powerhead, this engine delivered impressive acceleration, top-end power, and improved fuel efficiency — all in a lighter, more compact package compared to its predecessors.

Designed for a wide range of applications, the 300 V8 Four Stroke was equally at home on offshore center consoles, bay boats, and performance pontoons. It featured Advanced Range Optimization (ARO), Adaptive Speed Control (ASC), and optional Digital Throttle & Shift (DTS) for smoother handling and throttle response. While not branded under the “Verado” name, this model shared many of the same refinements, including quiet operation and a top-mounted service door for easier maintenance.

The 300 HP V8 became one of Mercury’s most popular high-horsepower offerings thanks to its balance of performance, efficiency, and low weight. As of 2023, it continues to be a top choice for boaters seeking modern reliability without the complexity of supercharging.

📆 Model Years Covered:

• Mercury 300 HP V8 FourStroke – 2019
• Mercury 300 HP V8 FourStroke – 2020
• Mercury 300 HP V8 FourStroke – 2021
• Mercury 300 HP V8 FourStroke – 2022
• Mercury 300 HP V8 FourStroke – 2023

📘 Manual Details:

• Model: Mercury 300 HP V8 CMS FourStroke
• Serial Numbers: 2B529482 and up
• Engine Type: EFI, V8, 4-Stroke
• Document Type: OEM Service & Repair Manual
• Manual ID: 90-8M0182078
• Language: English
• Publisher: Mercury Marine
• Pages: 900+ with full system coverage and diagnostic procedures

📚 Manual Sections Include:

• General Information & Specifications
• Ignition & Charging System
• ECM, ignition timing, stator, flywheel, voltage regulation
• Fuel System
• EFI diagnostics, fuel rail, high-pressure pump, SmartCraft components
• Powerhead
• Crankshaft, pistons, camshaft, valve train, oil system
• Cooling System
• Thermostats, impeller, cooling passages, bypass valves
• Midsection & Power Trim
• Trim actuator, swivel bracket, mounts, anti-vibration system
• Gearcase Assembly
• Propshaft, gear set, seals, shift rod, water intake system
• Control Linkage & Adjustment
• DTS or mechanical throttle control, shift sync, idle RPM
• Wiring Diagrams
• EFI, DTS, and SmartCraft schematics with full color coding

💾 Format & Compatibility:

• File Format: PDF
• Searchable & Bookmarked: ✅ Yes
• Printable: ✅ Yes – Full manual or selected sections
• Compatible With: Windows, macOS, iOS, Android, Linux
• Delivery: 📩 Instant Digital Download

🔍 Keywords:

Mercury 300 HP V8 FourStroke service manual PDF, 2019–2023 repair guide, EFI, DTS, SmartCraft, valve specs, wiring diagrams, gearcase repair

❓ Mini FAQ:

Q: Is this the full OEM manual for the Mercury 300 V8?
A: Yes – it's the complete Mercury factory service manual used by certified techs worldwide.

Q: Are all systems and diagnostics included?
A: Absolutely – EFI, DTS, SmartCraft, wiring, gearcase, and cooling are fully documented.

Q: Can I view it on my mobile device?
A: Yes – it’s fully compatible with all phones, tablets, laptops, and desktops.

🧭 Helpful Resources for Mercury Outboard Owners

• Why Every Mercury Mariner Owner Needs a Service Manual for At-Home Repairs – Learn how a digital service manual can save you time and money on common DIY maintenance tasks.
• Outboard Engine Troubleshooter – Not sure what’s wrong with your engine? Our free troubleshooting guide covers common issues across Mercury Outboards and more.

🔧 Browse More Mercury Manuals

Note: While our manuals are designed for DIY use, they do not replace professional mechanical training. If you're unsure about a repair or your engine shows serious issues, we strongly recommend visiting a certified marine mechanic. These guides are best suited for owners with basic to moderate mechanical experience.