YAMAHA Cdi Box 6H5-85540-00-00 50HP

( Manufacturer Part Number: 6H5855400000 ), ( Part Type: Box ), ( Compatible Model: 6h5-85540-00-00 ), ( Compatible Year: 1989-1992 )

Review YAMAHA Cdi Box 40 50hp fits 1989–2025

The **Yamaha CDI Box (Part Number: 6H5855400000 / 6H5-85540-00-00)** is a critical component for Yamaha outboard motors manufactured between **1989 and 1992**, specifically designed for models ranging from **25 horsepower to 50 horsepower**. This high-performance electronic ignition system is engineered to deliver precise, reliable spark generation, ensuring optimal engine performance, fuel efficiency, and longevity. Built with Yamaha s signature precision engineering, the CDI box integrates a robust **capacitor discharge ignition (CDI) circuit**, which provides a strong, consistent spark even under demanding conditions such as high RPMs, cold starts, or heavy loads. The unit features a **durable metal housing** for protection against moisture, vibration, and electrical interference, making it ideal for marine applications where reliability is paramount. Inside, a **high-quality transistorized circuit** regulates the ignition timing with exceptional accuracy, reducing misfires and enhancing throttle response. This component is fully compatible with Yamaha s **25, 40, and 50HP outboards** from the late 1980s and early 1990s, including models like the **Yamaha 25HP F15, 40HP F20, and 50HP F25 series**, ensuring seamless integration with the engine s ignition system. Whether restoring a classic boat or maintaining a vintage outboard, this CDI box is a **direct-fit, OEM-quality replacement** that restores factory performance, reduces wear on ignition components, and helps prevent costly engine damage from weak or inconsistent sparks. For enthusiasts and mechanics alike, it represents a **critical upgrade or restoration part** that bridges the gap between modern reliability and the classic Yamaha engineering of the era.

### **Pros and Cons of Buying a Yamaha 6H5855400000 (CDI Box for 1989 1992 25 40 50HP Outboards)**

#### **Pros**

1. **Reliability and Durability**

The Yamaha 6H5 series (1989 1992) is known for its robust construction and strong engine components. These outboards were designed for durability, making them suitable for both recreational and light commercial use. With proper maintenance, they can last for decades.

2. **Proven Performance**

The 25 50HP range in this series offers a good balance of power and efficiency for small to medium-sized boats. The 40HP and 50HP models, in particular, provide sufficient thrust for fishing boats, pontoons, and small cruisers without excessive fuel consumption.

3. **Availability of Parts and Serviceability**

As a well-established model, replacement parts (including the CDI box you mentioned) are still relatively easy to find, especially from Yamaha dealers or aftermarket suppliers. The engine s mechanical simplicity compared to modern electronics makes repairs more straightforward for those with basic mechanical skills.

4. **Lower Operating Costs**

Compared to newer outboards, these models typically consume less fuel and have fewer high-tech components that can fail or require expensive diagnostics. The CDI (Capacitor Discharge Ignition) system, while older, is reliable if maintained properly.

5. **Resale Value and Nostalgia Factor**

Classic Yamaha outboards hold value among collectors and enthusiasts. If you plan to keep the boat long-term or sell it later, the model s reputation can be an advantage. Additionally, some buyers appreciate the simplicity and "no-frills" nature of these engines.

6. **Compatibility with Older Boats**

If you re restoring or using a vintage boat, these outboards are a perfect fit. They re designed to work seamlessly with older hulls and drivetrain setups without requiring extensive modifications.

7. **Lower Initial Purchase Price**

Compared to modern outboards of similar horsepower, these used models are significantly cheaper, making them an attractive option for budget-conscious buyers.

---

#### **Cons**

1. **Outdated Technology**

The CDI system (which you re purchasing separately) is less efficient than modern electronic ignition systems. This can lead to slightly lower performance, rougher idling, or reduced fuel economy compared to newer outboards. The lack of modern fuel injection also means slightly less precise combustion.

2. **Maintenance Requirements**

- **Timing and Valve Adjustments:** Older engines often need periodic valve adjustments to maintain performance.

- **Fuel System Cleaning:** Carbureted models (common in this era) are prone to clogging from dirt or ethanol-blended fuels.

- **Cooling System Checks:** Older outboards are more susceptible to overheating if the cooling system isn t properly maintained.

- **Battery and Electrical Issues:** The CDI system relies on a reliable battery and wiring, which can degrade over time.

3. **Emissions and Environmental Concerns**

These outboards were not designed with modern emissions standards in mind. They may produce more pollutants than newer, EPA/CSA-certified engines, which could be a concern if you operate in environmentally sensitive areas or plan to use the boat in regions with strict emissions laws.

4. **Limited Modern Upgrades**

Unlike newer outboards, these models lack compatibility with modern accessories like GPS mounts, digital gauges, or electronic throttle controls. Upgrading to a modern outboard may be easier than retrofitting this one with contemporary features.

5. **Potential for Hidden Issues**

- **Worn Bearings or Gaskets:** Over time, internal components like bearings or gaskets may wear out, leading to oil leaks or reduced performance.

- **Rust and Corrosion:** If the outboard was stored improperly (e.g., in saltwater or without protection), rust can compromise structural integrity.

- **Fuel System Failures:** Carburetors or fuel lines can degrade, leading to hard starting or stalling.

6. **Insurance and Warranty Limitations**

Insuring an older outboard may be more expensive or difficult, depending on your provider. Most modern warranties won t cover these engines, so you ll need to budget for repairs out-of-pocket.

7. **Fuel Efficiency**

While these outboards are fuel-efficient by vintage standards, they won t match the efficiency of modern outboards with direct fuel injection and optimized combustion systems.

---

### **Conclusion**

The Yamaha 6H5 series (1989 1992) with a CDI box is a **solid, reliable choice** for buyers who prioritize durability, simplicity, and cost-effectiveness. It s ideal for:

- **Restoration projects** where you want a classic, high-quality outboard.

- **Budget-conscious buyers** who don t need the latest technology.

- **Light-duty applications** like fishing, small cruising, or pontoon boats.

- **Enthusiasts** who appreciate the engineering of an earlier era.

However, if you re looking for **modern performance, emissions compliance, or ease of maintenance**, a newer outboard (even a used one from the 2000s or later) would be a better investment. The trade-off is higher upfront costs and potentially more complex repairs.

---

### **Recommendation**

- You have experience maintaining older engines or are willing to learn.

- You re restoring a vintage boat or don t need the latest features.

- You find a well-documented unit with a clean service history (preferably with recent maintenance records).

- You re okay with slightly lower fuel efficiency and performance compared to modern outboards.

- You want a hassle-free, low-maintenance outboard with modern reliability.

- You plan to use the boat frequently in saltwater or harsh conditions without extensive upkeep.

- You re unsure about diagnosing or fixing mechanical issues.

- You need to comply with strict emissions regulations in your area.

- The condition of the lower unit (propeller shaft, bearings).

- The integrity of the cooling system (water pump, impeller, hull fitting).

- The health of the CDI system (test for proper spark and ignition timing).

- Signs of rust, leaks, or excessive wear in critical components.

If the outboard is in good shape and you re prepared for its maintenance needs, it s a **great value** for the money. If not, consider a newer used outboard (even a slightly older model from the 2000s) for better long-term reliability.

Details:

Used Yamaha Cdi box removed from a 1990 40.

part #: 6h5855400000 prices

• $299.99-$1370.61

specifications electricacompone:

• for makes: Yamaha
• for years: 1989-2025
• mpn: 6h5855400000
• part type: Box
• compatible model: 6h5-85540-00-00
• compatible year: 1989-1992

offer electricacompone:

• options: Ship-to-home
• availability: In Stock
• started: May 26, 2026
• sold: 0
• quantity: 1
• best offers: True

seller electricacompone:

• # reviews: 1
• city: Austin, Arkansas
• rating: 100.0%

general electricacompone:

• ATV, Side-by-Side UTV Parts Accessories > Electrical Ignition Components > Other Electrical Ignition Components
• condition: Used

shipping electricacompone:

• carrier: USPS
• type: Fixed
• service: USPS Ground Advantage
• class: Standard
• cost: $9.99
• transit: 4-10 Days

payments electricacompone:

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

returns electricacompone:

• policy: No Returns

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