MERCURY 859516 Optimax Outboard Fuel Rails Injectors 135 150 175HP 2.5 858221

( Manufacturer Part Number: 859516 ), ( Part Type: Fuel Injector )

Review MERCURY 135 150 175hp 2.5 Optimax Outboard Fuel Rails Injectors

Detailed Product Description for Mercury 859516 135/150/175hp 2.5 Optimax Outboard Fuel Rails Injectors (858221)

Experience unparalleled performance and reliability with the Mercury 859516 135/150/175hp 2.5 Optimax Outboard Fuel Rails Injectors (858221). Designed specifically for Mercury's Optimax outboard engines, these fuel injectors deliver precise fuel management for optimal engine efficiency and power output.

The 859516 fuel rails injectors are engineered to meet the demanding requirements of high-performance marine applications. With a flow rate of 260cc/min (135hp), 300cc/min (150hp), and 335cc/min (175hp), these injectors ensure a consistent fuel supply for smooth and responsive engine operation, even under heavy loads.

The injectors feature a robust, marine-grade construction that withstands the harsh conditions of the marine environment. The injectors are made from high-quality materials, including corrosion-resistant aluminum and hard-coated fuel tips, ensuring durability and longevity.

The Mercury 859516 fuel injectors are electronically controlled, offering precise fuel delivery for improved fuel economy and reduced emissions. The injectors are also compatible with Mercury's digital throttle and shift (DTS) systems, providing smooth and seamless shifting and throttle response.

Installation of the 859516 fuel rails injectors is straightforward, thanks to their plug-and-play design. The injectors are easy to install and require no modifications to the engine or fuel system.

In conclusion, the Mercury 859516 135/150/175hp 2.5 Optimax Outboard Fuel Rails Injectors (858221) are a must-have for any high-performance marine application. With their precise fuel management, durable construction, and easy installation, these injectors offer unmatched performance and reliability for your Optimax outboard engine. Upgrade your engine today and experience the difference that the Mercury 859516 fuel injectors can make.

Analysis of Mercury 859516 Outboard Fuel Rails, Injectors, and Throttle Bodies (135-175hp, 2.5 Optimax)

1. **Power Output:** This product offers a wide power range of 135-175hp, making it suitable for a variety of boating needs.

2. **Advanced Technology:** The 2.5 Optimax engine is known for its efficient combustion system, which can lead to improved fuel economy and reduced emissions.

3. **Reliable Brand:** Mercury Marine is a well-established brand with a reputation for quality and durability.

4. **Parts Compatibility:** These fuel rails, injectors, and throttle bodies are specifically designed for the Optimax engine, ensuring a perfect fit and seamless integration.

1. **Cost:** The price point of these components may be higher than some competing products, which could be a disadvantage for budget-conscious consumers.

2. **Availability of Spare Parts:** While Mercury Marine is a well-known brand, the availability of spare parts for these specific components may vary, especially for older models.

3. **Installation Complexity:** Installing these components may require professional assistance, which could add to the overall cost and inconvenience.

The Mercury 859516 outboard fuel rails, injectors, and throttle bodies offer a powerful and efficient solution for those seeking to upgrade their Optimax engine. However, the higher cost and potential complexity of installation may deter some users. If you are willing to invest in a reliable, high-performance system and have the means to install it, this product could be a good choice. Alternatively, if you are on a tight budget or prefer a simpler installation process, you may want to consider other options.

Details:

part #: 859516 prices

• $89.00-$224.99

specifications ouboaen:

• for makes: Mercury
• mpn: 859516
• part type: Fuel Injector

returns ouboaen:

• policy: No Returns

offer ouboaen:

• availability: In Stock
• started: September 17, 2025
• options: Ship-to-home
• quantity: 1
• best offers: True
• sold: 0

payments ouboaen:

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

seller ouboaen:

• rating: 98.1%
• city: Stuart, Florida
• # reviews: 2903

general ouboaen:

• Boat Parts > Outboard Engines Components > Intake Fuel Systems
• condition: Used

shipping ouboaen:

• carrier: FedEx
• class: Standard
• cost: $18.00
• type: Fixed
• transit: 3-9 Days
• service: FedEx Ground / FedEx Home Delivery

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