OMC 328336 Lower Unit Extension

( Brand: Omc ), ( Manufacturer Part Number: 328336 ), ( Part Type: Hp Unit ), ( Country Of Origin: United States )

Review OMC Evinrude Johnson Hp Lower Unit Extension P# Oe No Warranty fits 2025

The **OMC 328336 Evinrude Johnson 25 HP Lower Unit Extension** is a precision-engineered marine propulsion component designed exclusively for Evinrude and Johnson outboard motors in the 25 horsepower class, ensuring seamless compatibility and optimal performance. This lower unit extension serves as a critical link between the motor s drive shaft and the propeller, providing the necessary length and structural integrity to accommodate various hull configurations, from small fishing boats to recreational vessels. Crafted from high-grade marine-grade aluminum, this extension is built to withstand the rigors of saltwater environments, corrosion, and constant mechanical stress, offering both durability and reliability in demanding conditions. Its robust construction includes a reinforced drive shaft housing, precision-machined bearings, and a sealed gear case to minimize water intrusion and maximize efficiency, ensuring smooth power transmission from the motor to the propeller. Whether used for upgrading an existing setup, extending the drive length for better weight distribution, or adapting to a specific boat design, this lower unit extension delivers the performance and longevity expected from OMC s trusted marine components. With its straightforward installation and compatibility with a range of 25 HP Evinrude and Johnson outboards, it is an essential accessory for boat owners seeking to enhance their vessel s handling, efficiency, and overall performance.

### **Pros and Cons of buying a OMC 328336 Evinrude Johnson 25 HP Lower Unit Extension**

1. **Compatibility with Evinrude/Johnson Engines** This lower unit extension is specifically designed for Evinrude and Johnson outboard motors, ensuring a proper fit and reliable performance. It is compatible with the 25 HP series, which is common in smaller boats like kayak trollers, fishing boats, and personal watercraft.

2. **Extended Shaft Length** The extension allows for greater shaft length, which can be beneficial if your transom is too short for the stock lower unit. This prevents the motor from sitting too low in the water, improving cooling and reducing the risk of damage from shallow water or obstacles.

3. **Durability and Quality** OMC (Outboard Marine Corporation) is a well-known brand with a reputation for manufacturing reliable marine components. The lower unit extension is built to withstand the stresses of boating, including vibration and water exposure.

4. **Easy Installation** Designed to be a direct replacement, the extension should fit seamlessly with minimal modifications required. Many users report that installation is straightforward, especially if you have basic mechanical skills.

5. **Cost-Effective Upgrade** Compared to purchasing a new motor or modifying your transom, this extension is a relatively inexpensive solution to extend shaft length without sacrificing performance.

6. **Improved Handling and Performance** A properly extended shaft can enhance steering response and reduce strain on the motor, leading to smoother operation, especially in smaller boats where the motor s position affects balance.

7. **Widely Available Parts and Support** Since OMC is a major manufacturer, finding replacement parts, service manuals, or technical support is easier than with aftermarket or lesser-known brands.

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1. **Limited Compatibility** While it works with Evinrude and Johnson 25 HP motors, it may not fit other brands (e.g., Yamaha, Mercury) or different model years without additional modifications. Always verify compatibility before purchasing.

2. **Potential for Misalignment** If not installed correctly, the extension could cause misalignment between the motor and the lower unit, leading to premature wear on seals, bearings, or the propeller shaft.

3. **Weight Addition** The extension adds extra weight to the motor, which may slightly reduce fuel efficiency or require adjustments to the boat s balance, particularly in smaller vessels.

4. **Cost of Additional Components** If your existing lower unit or motor is outdated, you may need to upgrade other parts (e.g., a new propeller, shaft, or gasket) to ensure everything works together properly. This can increase the total cost beyond just the extension.

5. **Risk of Damage in Rough Conditions** If the extension is not securely fastened or if the motor is frequently run in shallow water, there s a risk of bending the shaft or damaging the lower unit.

6. **Limited Longevity in Extreme Conditions** While durable, prolonged exposure to saltwater corrosion (if not properly maintained) can degrade the extension over time, especially in older models.

7. **Professional Installation May Be Recommended** While DIY-friendly, improper installation can void warranties or cause long-term issues. If you re unsure, consulting a marine mechanic may be worth the extra cost.

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The **OMC 328336 Evinrude Johnson 25 HP Lower Unit Extension** is a practical and cost-effective solution for boat owners who need to extend their shaft length without replacing the entire motor. It offers **reliability, compatibility, and ease of installation**, making it a solid choice for smaller boats where proper motor positioning is critical. However, it is not a universal fix **compatibility must be confirmed**, and proper installation is essential to avoid performance issues or damage.

If your boat s transom is too short for the stock lower unit, this extension can **improve cooling, handling, and longevity** of your motor. That said, if your motor is already outdated or your boat requires significant modifications, you may need to weigh the extension against a full motor upgrade.

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- You have an **Evinrude or Johnson 25 HP motor** and need to extend the shaft length.

- Your boat s transom is too short for the stock lower unit, and you want to avoid modifying the transom itself.

- You re comfortable with **basic mechanical work** or have access to a mechanic for installation.

- You prioritize **cost efficiency** over a full motor replacement.

- Your motor is **not compatible** with this specific extension (double-check the model numbers).

- You plan to **run the motor in extremely shallow or rough waters** frequently, as improper installation could lead to damage.

- Your boat s **balance or performance issues stem from something other than shaft length** (e.g., an outdated motor or improper trim).

- You re unsure about installation **professional help may be necessary** to prevent long-term problems.

**Final Verdict:** For the right boat and motor, this extension is a **smart, budget-friendly upgrade** that can significantly improve your boating experience. Always verify compatibility and follow installation guidelines carefully.

Details:

Great condition.

part #: 328336 prices

• $30.00-$249.95

specifications ouboaen:

• for makes: Evinrude, Johnson, Omc
• for years: 2025
• brand: Omc
• mpn: 328336
• part type: Hp Unit
• country of origin: United States

seller ouboaen:

• city: Lodi, California
• rating: 94.4%
• # reviews: 48

general ouboaen:

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

returns ouboaen:

• policy: No Returns

offer ouboaen:

• availability: In Stock
• options: Ship-to-home
• sold: 0
• started: May 10, 2026
• quantity: 1
• best offers: True

shipping ouboaen:

• service: USPS Ground Advantage
• transit: 5-12 Days
• cost: $15.00
• type: Fixed
• carrier: USPS
• class: Standard

payments ouboaen:

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