MERCURY 8M0028851 Outboard Switch Box 50HP 3-CYL 2-STR T155

( Manufacturer Part Number: 8M0028851 ), ( Part Type: Switch Box ), ( Country Of Origin: United States )

Review MERCURY 50hp 3-cyl Outboard Switch Box fits 1989

The **Mercury 8M0028851 1989 50HP 3-Cylinder Two-Stroke Outboard Switch Box (T155)** is a meticulously engineered electrical control module designed exclusively for Mercury s iconic 50 horsepower three-cylinder two-stroke outboard motors from the late 1980s, including the highly sought-after models from 1989. This switch box serves as the central hub for the outboard s ignition, throttle, and starter systems, ensuring seamless operation while maintaining the reliability and performance that Mercury outboards are renowned for. Crafted with durability in mind, the T155 switch box features a robust, corrosion-resistant construction, allowing it to withstand the harsh marine environment whether exposed to saltwater, humidity, or prolonged sun exposure. Its compact yet functional design houses a series of precision-engineered switches, including the ignition kill switch, starter solenoid, and throttle control levers, all of which are wired to the outboard s electrical system with high-quality marine-grade cables to prevent wear and tear. The switch box is compatible with the 1989 50HP three-cylinder two-stroke outboard s wiring harness, ensuring a perfect fit and reliable connectivity. Whether you re restoring a classic Mercury outboard or maintaining an older model, this switch box is a critical component that guarantees smooth electrical operation, from easy starting to precise throttle control. Its timeless design reflects Mercury s commitment to performance and longevity, making it a valuable addition for any enthusiast looking to preserve or enhance the functionality of their vintage outboard.

### **Pros and Cons of Buying a Mercury 8M0028851 (1989, 50HP, 3-Cylinder, 2-Stroke Outboard) with Switch Box (T155)**

1. **Reliability for Basic Use** The 50HP 3-cylinder 2-stroke outboard from 1989 was designed for small boats, trolling, and light fishing. If maintained properly, it can still provide dependable power for recreational use, especially on calm waters.

2. **Affordability** Older outboards like this are significantly cheaper than newer models, making them an attractive option for budget-conscious buyers. Parts and labor may also be less expensive compared to modern engines.

3. **Simplicity** The mechanical design is straightforward, which means repairs and adjustments can be easier for those with basic mechanical skills. Many classic outboard components are still available through marine parts suppliers.

4. **Switch Box (T155) Compatibility** The T155 switch box is a common aftermarket unit designed for older Mercury outboards, allowing for easy starting and control. This can be a useful upgrade if the original wiring is worn or unreliable.

5. **Potential for Restoration** If you enjoy working on projects, this engine could be a fun restoration challenge. With proper care, it may regain near-new performance.

6. **Good for Small Boats** If paired with a suitable vessel (e.g., a 14 16 ft bass boat, canoe, or kayak), it provides adequate power for trolling, shallow water fishing, or leisurely cruising.

7. **Lower Fuel Consumption** 2-stroke outboards generally consume fuel more efficiently than modern 4-strokes for light-duty use, though they require a fuel-oil mix.

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1. **Age and Wear** A 1989 engine has likely accumulated significant mileage and wear. Internal components like pistons, bearings, and the crankshaft may be near the end of their lifespan, leading to potential breakdowns.

2. **Environmental Concerns** 2-stroke outboards are known for higher emissions and oil pollution since they mix oil with fuel. Many marinas and waterways now restrict or ban them due to environmental regulations.

3. **Reliability Issues** Older outboards are prone to leaks (oil, coolant, or fuel), ignition problems, and overheating. The carburetion may also be less precise, leading to rough idling or poor performance.

4. **Limited Power for Demanding Use** At 50HP, this engine is underpowered for anything beyond light use. It may struggle with waves, heavy loads, or prolonged high-speed operation.

5. **Maintenance Requirements** Regular maintenance (oil changes, spark plug replacements, carburetor cleaning, and gasket checks) is essential to keep it running. Neglect can lead to costly repairs.

6. **Parts Availability** While parts exist, some may be harder to find than for newer models. Mercury has phased out many older components, requiring sourcing from specialty suppliers.

7. **Resale Value** Even if well-maintained, the resale value of a 1989 2-stroke outboard is low compared to modern alternatives.

8. **Noise and Vibration** Older outboards tend to be louder and vibrate more than modern engines, which can be uncomfortable for extended use.

9. **Legal Restrictions** Some states or countries have banned or restricted 2-stroke outboards due to environmental regulations. Check local laws before purchasing.

10. **Potential Hidden Damage** Without a thorough inspection (including an engine pull and inspection of the lower unit), there could be internal damage (e.g., cracked pistons, worn bearings) that isn t immediately obvious.

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- Have a small boat for light, occasional use (e.g., trolling, calm-water fishing).

- Are willing to invest time and money in maintenance and potential repairs.

- Don t mind the environmental drawbacks and are aware of local regulations.

- Enjoy working on projects and restoring classic equipment.

However, if you prioritize **reliability, environmental compliance, or modern performance**, this engine may not be the best long-term choice. Modern 4-stroke outboards (even small ones) offer better fuel efficiency, lower emissions, and longer lifespan with less maintenance hassle.

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- **Buy if:** You need a low-cost, low-power engine for a small boat and are prepared to maintain it rigorously. Consider pairing it with a **T155 switch box** for better control and a **fuel stabilizer** to extend its life.

- **Don t buy if:** You want a hassle-free, reliable engine for frequent or demanding use, or if you re concerned about environmental regulations.

- A **used 4-stroke outboard** (e.g., Yamaha 50HP 4-stroke) for better reliability and emissions compliance.

- A **new or lightly used small outboard** (e.g., Honda BF50 or Mercury 50HP 4-stroke) if budget allows.

- A **hybrid or electric outboard** for ultra-low maintenance and eco-friendly operation.

**Final Verdict:** This engine is a **good budget option for hobbyists or those with minimal demands**, but it s not ideal for serious boaters. Always have it **thoroughly inspected** (including an engine pull) before purchasing to avoid costly surprises.

Details:

Pleasured entire listing before buying or purchasing item. Just because the part looks right does not mean that Otis. We operate in Central Standard Time. They will however be in functioning and usable condition.

Recombine shipping on multiple items. Keeping mind that if the listing is for a used part, it used part, so there may be some minor cosmetic damage scratches/scuffs. Parts off of a 1989 Mercury 50hp 3-cylinder, 2-Stroke freshwater outboard motor, model 10604129D, serial 0C213633, long shaft for 20 transoms, tiller steer, electric start, power head had poor compression.

part #: 8m0028851 prices

• $74.99-$199.00

specifications ouboaen:

• for makes: Mercury
• for years: 1989
• mpn: 8m0028851
• part type: Switch Box
• country of origin: United States

seller ouboaen:

• rating: 99.9%
• city: Melrose, Minnesota
• # reviews: 5488

shipping ouboaen:

• cost: $0.00
• class: Standard
• type: Fixed
• transit: 2-6 Days
• service: Standard

general ouboaen:

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

payments ouboaen:

• credit card: Mastercard
• other
• wallet: Paypal

returns ouboaen:

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

offer ouboaen:

• started: April 14, 2026
• quantity: 1
• options: Ship-to-home
• availability: In Stock
• sold: 0

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