MERCURY 821306T12 Outboard Lower Unit Gearcase Gear 40 50 2-STROKE

( Manufacturer Part Number: 821306T12 ), ( Part Type: Hp Unit Gear Case ), ( Stroke: 2-stroke )

Review MERCURY Outboard 40 50 Hp 2-stroke Lower Unit Gearcase Long Gear Case fits MARINER

Mercury Mariner Outboard 40-50 HP 2-Stroke Lower Unit Gearcase - Model 821306T12

Experience unparalleled power and efficiency with the Mercury Mariner Outboard 40-50 HP 2-Stroke Lower Unit Gearcase - Model 821306T12. This exceptional piece of marine engineering is designed to deliver exceptional performance, reliability, and durability, making it an ideal choice for a wide range of watercraft applications.

The Mercury Mariner Outboard's 40-50 HP engine offers a perfect blend of power and economy, ensuring you can navigate through various water conditions with ease and confidence. The 2-stroke design offers simplified maintenance and fewer parts, making it a practical choice for boaters who value efficiency and convenience.

The lower unit gearcase, model 821306T12, is a testament to Mercury's commitment to quality and performance. It features a robust, corrosion-resistant construction that withstands the harshest marine environments. The gearcase is designed for optimal torque and thrust, ensuring quick acceleration and smooth, responsive handling.

The gearcase is equipped with a high-quality, durable gear system that delivers excellent power transfer from the engine to the propeller. This ensures optimal performance in various water conditions, from calm lakes to turbulent seas. The gearcase also features a premium, self-lubricating bearing system, reducing maintenance requirements and extending the lifespan of the unit.

In addition, the Mercury Mariner Outboard 40-50 HP 2-Stroke Lower Unit Gearcase - Model 821306T12 is designed for easy installation and integration with various Mercury outboard engines. It is compatible with a wide range of propellers, allowing you to customize your boat's performance to suit your specific needs.

With its powerful performance, durable construction, and user-friendly design, the Mercury Mariner Outboard 40-50 HP 2-Stroke Lower Unit Gearcase - Model 821306T12 is an excellent choice for boaters who demand the best in marine propulsion technology. Experience the power, reliability, and efficiency of the Mercury Mariner Outboard today and elevate your boating adventures to new heights.

Pros and Cons of Buying Mercury 821306T12 Mariner Outboard 40-50 HP 2-Stroke Lower Unit Gearcase Gear

1. Powerful and Versatile: The Mercury 821306T12 Mariner outboard motor offers a power range of 40 to 50 HP, making it suitable for a variety of small boats and watercraft.

2. 2-Stroke Design: Two-stroke engines are known for their simplicity, lightweight, and high power-to-weight ratio, which can be beneficial for quick acceleration and maneuverability.

3. Durable Lower Unit: The lower unit of this outboard is designed for durability, with features like a cast aluminum gearcase and a heavy-duty lower unit bearing that can withstand rigorous use.

4. Easy Maintenance: Two-stroke engines require regular oil mixing, but they are generally easier to maintain compared to four-stroke engines due to fewer moving parts.

1. Fuel Consumption: Two-stroke engines are less fuel-efficient than four-stroke engines. If fuel economy is a priority, a four-stroke outboard might be a better choice.

2. Noise and Vibrations: Two-stroke engines can be noisier and produce more vibrations than four-stroke engines, which might be a concern for some users.

3. Regular Oil Mixing: Unlike four-stroke engines, two-stroke engines require oil to be mixed with fuel, which can add an extra step to the maintenance process.

4. Emissions: Two-stroke engines can produce more harmful emissions than four-stroke engines, contributing to environmental pollution.

The Mercury 821306T12 Mariner Outboard 40-50 HP 2-Stroke Lower Unit Gearcase Gear is a powerful and versatile option for small boats. Its simplicity, lightweight, and high power-to-weight ratio make it suitable for quick acceleration and maneuverability. However, its higher fuel consumption, noise levels, vibrations, and emissions might be drawbacks for some users, especially those prioritizing fuel economy, quiet operation, and environmental friendliness.

If you prioritize power, simplicity, and affordability, the Mercury 821306T12 Mariner Outboard could be a good choice. However, if you value fuel efficiency, quiet operation, and environmental friendliness, you might want to consider a four-stroke outboard engine. Always consider your specific needs, the type and size of your boat, and your budget before making a decision.

Details:

The gear lube looked good, but it will need new and drain plug gaskets before putting back into service. Prop shaft: 13 splines. This was removed from a 2003 Mercury 50 HP, 3 cylinder, 2 stroke, carburetors, 20 inch outboard. Engine SN 0T670085.

This unit smoothly shifts into forward, neutral, and reverse as it should. The gear lube was drained out to check for water or metal shavings. These parts may fit other years and model's. This unit was also pressure and vacuum tested showed no leakage in either direction.

Please verify before purchasing. Driveshaft: 14 splines. I would also recommend installing a new impeller.

part #: 821306t12 prices

• $269.66-$1100.00

specifications ouboaen:

• for models: Mariner
• for makes: Mercury
• mpn: 821306t12
• part type: Hp Unit Gear Case
• stroke: 2-stroke

offer ouboaen:

• availability: In Stock
• sold: 0
• quantity: 1
• started: June 29, 2025
• options: Ship-to-home

shipping ouboaen:

• type: Fixed
• cost: $0.00
• service: Economy
• class: Economy
• transit: 4-9 Days

returns ouboaen:

• paid by: Buyer
• policy: Returns Accepted
• time: 14 Days

payments ouboaen:

• wallet: Paypal
• other
• credit card: Diners-club

general ouboaen:

• condition: Used
• Boat Parts > Outboard Engines Components > Complete Outboard Lower Units

seller ouboaen:

• city: Milledgeville, Georgia
• # reviews: 487
• rating: 99.4%

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