OMC COBRA Sterndrive Upper Unit 0985684 3.0L 0720

( Brand: Omc Cobra ), ( Manufacturer Part Number: 985684 ), ( Part Type: Sterndrive Unit ), ( Disclaimer: All Parts Come As Pictured. )

Review OMC COBRA Month Warranty 3.0l Sterndrive Upper Unit fits 2018–2021

The **OMC Cobra 985684 (Model 0985684) 21" 18" 3.0L Sterndrive Upper Unit** is a high-performance marine propulsion system engineered for speed, reliability, and precision, making it an ideal choice for enthusiasts seeking a balance between raw power and refined handling. Designed with a **3.0-liter inline-four engine**, this upper unit delivers a robust torque output, ensuring swift acceleration and effortless cruising across open water or tight turns. The **21" x 18" propeller shaft** is precision-machined to minimize vibration and maximize efficiency, while the **integrated gearcase** provides a seamless transfer of power with minimal energy loss, allowing for optimal performance whether you're racing, fishing, or simply enjoying a day on the water.

Built with **marine-grade aluminum and high-strength steel components**, this upper unit is constructed to withstand the harshest conditions, from saltwater corrosion to heavy loads. The **sealed and lubricated shaft bearings** ensure smooth operation while reducing maintenance demands, making it a durable long-term investment. The **adjustable trim and tilt mechanism** allows for precise control over ride height and angle, enhancing stability at high speeds and improving maneuverability in choppy waters. Whether you're navigating a crowded marina or carving through waves at full throttle, the Cobra s ergonomic design and responsive controls provide a commanding feel, putting you in full control of your vessel s performance.

For those who demand both aesthetics and functionality, the **sleek, streamlined housing** not only enhances the visual appeal of your boat but also reduces drag, contributing to better fuel efficiency and higher top speeds. The **quick-release mounting system** simplifies installation and removal, making it easy to service or swap out components when needed. Additionally, the **integrated cooling system** ensures optimal engine temperature regulation, preventing overheating and prolonging the lifespan of critical components. Whether paired with a high-performance outboard or integrated into a custom sterndrive setup, this upper unit delivers a **smooth, powerful, and dependable** driving experience, making it a standout choice for discerning boat owners who refuse to compromise on quality or performance.

### **Pros and Cons of Buying an OMC Cobra 985684 (0720) 3.0L Sterndrive Upper Unit**

1. **Reliability and Durability** The OMC Cobra series, particularly the 3.0L models, is known for its robust construction and strong performance in both freshwater and saltwater applications. The 0720 model (manufactured around 2007 2010) is a well-regarded unit with a proven track record for longevity when properly maintained.

2. **Power and Performance** The 3.0L engine provides a good balance of power and efficiency, making it suitable for mid-sized boats (18 25 feet). It delivers adequate thrust for cruising, fishing, and light planing, depending on the propeller selection.

3. **Compatibility with Common Boats** The 985684 model is designed to fit a variety of outboard-equipped boats, including older models that may not support newer, more complex electronic systems. Its mechanical simplicity makes it easier to work with for DIYers.

4. **Lower Cost of Ownership (Compared to New Units)** As a used unit, this model is significantly cheaper than a new OMC or Mercury Verado engine. Parts and labor costs are also lower than for newer, more advanced systems.

5. **Proven Design** The Cobra series was a reliable workhorse before newer models like the Verado were introduced. Many boaters prefer its straightforward design over more complex electronic fuel injection systems.

6. **Good for Saltwater Use** The 3.0L Cobra is built to handle saltwater exposure better than some older outboards, though regular flushing and maintenance are still required to prevent corrosion.

7. **Easier to Service Than Modern Units** Unlike newer engines with advanced diagnostics and electronic controls, the Cobra s mechanical nature makes troubleshooting and repairs more accessible for those with basic mechanical skills.

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1. **Age and Wear** This is a late-2000s model, meaning it may have accumulated significant mileage or wear. If not well-maintained, it could require major repairs (e.g., cylinder head gasket failure, rod bearing wear) sooner rather than later.

2. **Fuel Efficiency** The 3.0L Cobra is not as fuel-efficient as newer, more advanced engines. It consumes more gas than a modern outboard of similar horsepower, increasing operating costs.

3. **Emissions and Modern Regulations** Older engines like this may not meet current emissions standards in some regions, though they are often grandfathered in. If you plan to use the boat in highly regulated areas, check local laws.

- Electronic fuel injection tuning

- Shift-on-the-fly (for some models)

- Built-in diagnostics

- Smart throttle integration

- GPS or engine monitoring systems

5. **Part Availability** While still available, some original parts (especially for older models) may become harder to find over time. Aftermarket or remanufactured parts may be necessary, which could affect reliability.

- Cracked or worn impellers

- Leaking seals or gaskets

- Internal corrosion (if previously used in saltwater without proper care)

- Electrical or ignition problems

7. **Lower Resale Value** Even in good condition, an older Cobra will depreciate faster than a newer outboard. If you plan to sell later, you may not recover as much as with a more modern unit.

8. **Noise and Vibration** Older engines can be noisier and vibrate more than newer, refined models. This may affect comfort, especially in smaller boats.

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The **OMC Cobra 985684 (0720) 3.0L sterndrive upper unit** is a solid, reliable choice for boaters who prioritize **durability, simplicity, and cost-effectiveness** over the latest technology. It is well-suited for:

- **Budget-conscious buyers** who want a proven engine without the high cost of a new unit.

- **DIY mechanics** who prefer working with mechanical systems rather than complex electronics.

- **Owners of older boats** that require a compatible, mid-sized outboard.

- **Saltwater users** who maintain their engine properly (though corrosion is still a risk).

However, if you want **better fuel efficiency, modern features, quieter operation, or easier diagnostics**, a newer OMC Verado or Mercury outboard would be a more advanced (and expensive) alternative.

You have a **limited budget** and can afford potential future repairs.

You **prefer simplicity** and don t need advanced electronics.

The boat is **small to mid-sized** (18 25 feet) and doesn t require extreme performance.

You **plan to maintain it well** (regular oil changes, impeller checks, saltwater flushing if applicable).

You **don t mind slightly higher fuel consumption** compared to newer engines.

You need **modern features** like shift-on-the-fly or electronic diagnostics.

The engine has **high mileage or unclear maintenance history** (get a professional inspection).

You plan to **use it heavily in saltwater without proper care** (risk of corrosion).

You want **maximum fuel efficiency or low operating costs** (a newer 3.0L or 4.0L outboard may be better).

You re buying **without a test run or inspection** always check for leaks, unusual noises, or performance issues.

This is a **good used purchase for the right buyer** someone who values **reliability over cutting-edge technology** and is willing to invest in maintenance. If you can find it in **good condition with a clean service history**, it will serve you well for years. However, if you want the **latest efficiency and features**, a newer outboard may be worth the extra cost.

Details:

6 Month, Hassle Free Warranty, From Purchase Date. Good Condition, Ready To Install.

part #: 985684 prices

• $32.99-$1700.00

specifications ouboaen:

• for makes: Omc
• for years: 2018-2021
• brand: Omc Cobra
• mpn: 985684
• part type: Sterndrive Unit
• disclaimer: All Parts Come As Pictured.

general ouboaen:

• condition: Used
• Boat Parts > Outboard Engines Components > Other

offer ouboaen:

• sold: 0
• started: February 3, 2026
• availability: In Stock
• quantity: 1
• options: Ship-to-home

payments ouboaen:

• wallet: Google-pay
• other
• credit card: Discover

shipping ouboaen:

• carrier: FedEx
• service: FedEx Ground / FedEx Home Delivery
• transit: 3-8 Days
• cost: $95.00
• type: Fixed
• class: Standard

seller ouboaen:

• # reviews: 35620
• rating: 99.5%
• city: Gardena, California

returns ouboaen:

• paid by: Buyer
• time: 30 Days
• policy: Returns Accepted

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