1. Boat Outboard Engines To Buy
  2. sku: 21696256074210881
  3. MERCURY 1390-8889A15

MERCURY 1390-8889A15 Carb Rebuildable Wmc 20/25HP 45 1390-8889T21

fits make: Mercury.

1390-8889t21 Mercury 1390-8889a15 20/25hp Carb Rebuildable Wmc 45

( Manufacturer Part Number: 1390-8889A15 )

Review MERCURY 20/25hp Carb Rebuildable Wmc 45

The **Mercury 1390-8889A15 20/25 HP Carburetor Rebuildable Kit** (part number **1390-8889T21** for WMC 45 engines) is a meticulously engineered replacement kit designed to restore peak performance and reliability to your Mercury outboard motor s carburetion system. This high-quality rebuildable kit is specifically tailored for the **Mercury 20/25 HP WMC 45 series**, ensuring a precise fit and optimal fuel delivery for smooth, efficient operation. Crafted from durable materials, the kit includes a **comprehensive set of components** such as the carburetor body, throttle and choke linkages, gaskets, seals, and precision-machined internals all engineered to meet or exceed OEM specifications. The **rebuildable design** allows for easy maintenance, enabling you to disassemble, clean, and reassemble the carburetor with confidence, extending its lifespan and preventing costly engine wear. Whether you're preparing for a new season of boating or addressing performance issues, this kit provides a straightforward solution to recalibrate your engine s fuel mixture, ensuring better throttle response, reduced fuel consumption, and enhanced power output. Ideal for both DIY enthusiasts and professional mechanics, the **Mercury 1390-8889A15** rebuild kit combines durability with ease of installation, making it an essential upgrade for maintaining your outboard s optimal functioning.

### **Pros and Cons of Buying a Mercury 1390-8889A15 (20/25HP Carb Rebuildable WMC 45) Engine**

#### **Pros:**

1. **Proven Reliability** The Mercury 20/25HP engine is a well-established design with decades of use in small boats, trolling motors, and other marine applications. Many owners report long-term durability if properly maintained.

2. **Rebuildable Carburetor** The carburetor (likely a **WMC 45**) is designed to be rebuilt rather than replaced, which can save money in the long run. A rebuild kit is often cheaper than buying a new carb, and it can restore performance to near-new levels.

3. **Affordable Replacement Parts** Mercury s 20/25HP engines have a wide availability of aftermarket and OEM parts, including gaskets, seals, pistons, and carburetor components. This makes repairs and upgrades relatively inexpensive.

4. **Good for Light-Duty Use** If you re using it for trolling, small fishing boats, or occasional outings, this engine is more than capable. It provides smooth power without excessive fuel consumption.

5. **Easy to Maintain** Compared to modern outboard engines, these older Mercurys are simpler in design, meaning fewer complex systems to go wrong. Basic maintenance (oil changes, spark plug checks, carb adjustments) keeps them running well.

6. **Classic Build Quality** Mercury engines from this era were known for solid construction, with cast iron blocks and forgings that hold up well over time.

7. **Modifiable for Performance** With the right upgrades (e.g., larger jets, performance pistons, or a rebuilt carb), you can improve throttle response and fuel efficiency.

8. **Lower Initial Cost** Compared to modern outboards, this engine is significantly cheaper to purchase, making it a budget-friendly option for basic boating needs.

---

#### **Cons:**

1. **Age-Related Wear** Even if the engine is in good condition, it s an older design (likely from the 1970s 1990s), meaning some components (like bearings, seals, and gaskets) may be worn out and require replacement.

2. **Fuel Efficiency Concerns** Modern engines are far more fuel-efficient than the 20/25HP Mercury. You ll likely burn more gas per hour compared to a newer, smaller outboard or electric trolling motor.

3. **Emissions and Environmental Regulations** Some areas have restrictions on older, less efficient engines. If you plan to use it in environmentally sensitive waters, check local regulations.

4. **Limited Warranty (If Any)** Most used engines of this age come with no warranty. If you buy new, Mercury s warranty may not cover long-term wear issues.

5. **Carburetor Sensitivity** The WMC 45 carburetor can be finicky, requiring occasional tuning for proper fuel-air mixture. If not adjusted correctly, it may run poorly or flood.

6. **Hardware Compatibility Issues** Some newer boats or trolling motor mounts may not fit perfectly, requiring custom adapters or modifications.

7. **Resale Value is Low** Unlike newer engines, this model won t hold much value if you decide to sell it later.

8. **Potential for Hidden Problems** Without a thorough inspection (or a trusted mechanic s review), you might inherit issues like:

- **Worn crankshaft bearings**

- **Leaking head gaskets**

- **Stiff or seized valves**

- **Corroded or damaged internals** (if stored improperly)

9. **Limited Aftermarket Support** While parts exist, some specialized components (like exact carburetor jets or seals) may be harder to find than in newer engines.

10. **Noise and Vibration** Older engines tend to be louder and vibrate more than modern counterparts, which can be noticeable in quiet boating environments.

---

### **Conclusion:**

The **Mercury 1390-8889A15 (20/25HP Carb Rebuildable WMC 45)** is a **solid, budget-friendly choice** for light-duty boating, trolling, or small fishing applications. It offers **reliability, rebuildability, and affordability**, making it a good option if you:

- Need a **simple, low-maintenance engine** for occasional use.

- Are willing to **invest time in maintenance** (carb tuning, oil changes, gasket replacements).

- Don t require **high performance or fuel efficiency** compared to modern alternatives.

However, if you re looking for **long-term reliability without maintenance hassles**, a **newer, smaller outboard (e.g., Yamaha 6HP, Johnson 5HP, or even an electric trolling motor)** may be a better investment. These modern engines offer **better fuel economy, lower emissions, and fewer repair headaches**.

If you **inspect the engine thoroughly** (or have a mechanic check it) and are prepared for **potential rebuilds**, this Mercury can be a **cost-effective powerplant** for basic boating needs.

### **Recommendation:** - **Buy it if:**

- You need a **cheap, reliable engine** for a small boat or trolling.

- You re comfortable with **basic maintenance and occasional carb adjustments**.

- You plan to **use it sparingly** (e.g., a weekend fishing boat).

- You find a **well-documented, low-hour example** with a clean bill of health.

- **Avoid it if:**

- You want **modern efficiency and low maintenance**.

- You re using it **heavily or in rough conditions** (risk of premature wear).

- You **can t commit to regular upkeep** (carb tuning, oil changes, gasket replacements).

- You prefer **quieter, smoother-running engines** (modern outboards or electric trolling motors).

**Alternative Considerations:**

- **Newer 6 10HP outboards** (e.g., Yamaha 6HP, Evinrude 8HP) More efficient, quieter, and easier to maintain.

- **Electric trolling motors** (e.g., Minn Kota, MotorGuide) Zero emissions, ultra-smooth, and great for fishing.

- **Rebuilt Mercury 20/25HP** If you find one that s **already professionally rebuilt**, it may be a safer bet than a used one.

**Final Verdict:** The Mercury 20/25HP is a **good used engine for the right owner**, but not the best long-term choice if you want modern convenience. **Test it thoroughly before buying, and be prepared for maintenance.**

Details:

Carb Off a 1996 Mercury 25HP 2 stroke. Electric choke operates and was bench tested before listing for sale. I have tons of Mercury 25HP Parts. Good rebuildable carb.

All parts are here.

part #: 13908889a15 prices

  • $199.99-$230.00

specifications ouboaen:

  • for makes: Mercury
  • mpn: 1390-8889a15

payments ouboaen:

  • other
  • wallet: Paypal
  • credit card: Mastercard

offer ouboaen:

  • quantity: 1
  • started: January 31, 2026
  • availability: In Stock
  • options: Ship-to-home
  • sold: 0
  • best offers: True

seller ouboaen:

  • rating: 0.0%
  • # reviews: 0
  • city: Montoursville, Pennsylvania

returns ouboaen:

  • policy: No Returns

general ouboaen:

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

shipping ouboaen:

  • cost: $14.00
  • class: Standard
  • type: Fixed
  • carrier: USPS
  • transit: 4-9 Days
  • service: USPS Ground Advantage
for makes: mercury,
category: boat parts > outboard engines components, sku: 21696256074210881,
Mercury 1390-8889A15 Is Similar To:
ouboaen logo
3 offers $199.99–$230.00 USD
  • Used. Offer #1 priced at $199.99 + $19.60 shipping estimate = $219.59* total. +$19.60 shipping
  • Offer #2 priced at $230.00 + $0.00 shipping estimate = $230.00* total. FREE SHIPPING
  • Offer #3 priced at $230.00 + $0.00 shipping estimate = $230.00* total. FREE SHIPPING

Copyright © ouboaen.com