BFO QUXR70 Carburetor Tohatsu Outboard 4HP 5HP 853720T25 NSF5B

( Brand: Bfo ), ( Manufacturer Part Number: QUXR70 ), ( Part Type: 5hp Carburetor ), ( California Prop 65 Warning: California Prop 65 Warning ), ( Country Of Origin: China ), ( Engine Position: Outboard ), ( Fitment: For 4-stroke 4hp 5hp Outboard Motor, For Tohatsu 4-stroke 4hp 5hp, For Mercury 4-stroke 4hp 5hp ), ( Horse Power: 4hp, 5hp ), ( Oe/part Number: 3r1-03200-1, 3as-03200-0, 3gv-03200-0, 803522t1, 803522t2, 803522t03, 803522t04, 803522t05, 803522t06, 803522a04, 803522t02, 8m0053670, 853720t25, 898103t51, 889246t10 ), ( Replace Part Number: 3r1032001, 3r1-03200-1, 853720t25, 803522t03, Carburetor, Carburettor, Carburetter, Carb, Carby, Outboard Carburetor, Outboard Motor Carburetor, 4 Stroke Outboard Carburetor ), ( Warranty: 2 Year )

Review BFO Carburetor Assembly Mercury Tohatsu 4hp 5hp Outboard

The **BFO QUXR70 Carburetor** is a meticulously engineered, high-performance replacement part designed specifically for Mercury and Tohatsu outboard motors in the 4HP and 5HP displacement range, corresponding to the model numbers **853720T25** and **NSF5B**. Crafted with precision and built to exacting standards, this carburetor is a direct-fit solution that restores optimal fuel delivery, throttle response, and overall engine efficiency to your marine powerplant. The QUXR70 features a robust, corrosion-resistant construction, incorporating high-grade materials that ensure durability even in the harshest marine environments, where saltwater, humidity, and constant exposure to the elements can degrade standard components. Its advanced design incorporates a refined fuel metering system, including a precisely calibrated jet assembly and a smooth-operating throttle valve, which work in tandem to deliver a consistent and optimal air-fuel mixture for peak performance. Whether you're running a small fishing boat, a personal watercraft, or a utility vessel, this carburetor ensures reliable starts, smoother acceleration, and reduced fuel consumption, allowing your engine to operate at its intended capacity without the wear and tear of a clogged or degraded original unit. The QUXR70 is not just a replacement part it s an upgrade that enhances the longevity of your outboard by maintaining clean combustion and minimizing carbon buildup, a common issue in older carburetors. Backed by BFO s reputation for quality and compatibility, this carburetor is an ideal choice for both DIY enthusiasts and professional mechanics looking to restore or upgrade their Mercury or Tohatsu engines with confidence.

### **Pros and Cons of Buying a BF&O QUXR70 Carburetor for Mercury/Toledo 4HP-5HP Outboards (853720T25, NSF5B)**

1. **Compatibility and Fitment** The BF&O QUXR70 is specifically designed for Mercury/Toledo 4HP-5HP outboards, including the 853720T25 and NSF5B models. It is a direct replacement, ensuring proper installation without modifications.

2. **Improved Performance** Many users report better throttle response, smoother operation, and increased power compared to stock carburetors. The QUXR70 is often favored for its refined fuel-air mixture control.

3. **Durability and Quality** BF&O (Briggs & Stratton Outboard) is a well-regarded brand known for manufacturing reliable carburetors. The QUXR70 is built to withstand the demands of marine engines, reducing the risk of premature failure.

4. **Easier Maintenance** The design allows for straightforward cleaning and adjustment, which can extend the life of the carburetor and improve long-term reliability.

5. **Cost-Effective Upgrade** Compared to full engine replacements or major overhauls, replacing just the carburetor is a relatively inexpensive way to restore performance and efficiency.

6. **Aftermarket Support** BF&O carburetors are widely available through marine parts suppliers, making replacements and repairs easier if needed.

7. **Reduced Fuel Consumption** A properly tuned carburetor can optimize fuel efficiency, leading to lower operating costs over time.

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1. **Potential Learning Curve** If you are not familiar with carburetor tuning, adjusting the QUXR70 may require some trial and error to achieve optimal performance. Improper adjustments can lead to rough idling, stalling, or poor power delivery.

2. **Compatibility with Modified Engines** If the outboard has been heavily modified (e.g., with performance kits or aftermarket components), the QUXR70 may not perform as expected without additional tuning.

3. **Availability and Lead Times** While BF&O parts are generally easy to find, stock levels can vary depending on the supplier. In some cases, you may need to order from specialty marine stores, which could result in shipping delays.

4. **Cost Compared to Stock Replacement** While the QUXR70 is affordable, it may still be more expensive than a generic or aftermarket alternative. However, the performance gains often justify the cost.

5. **Risk of Installation Errors** If not installed correctly (e.g., improper gasket sealing, incorrect linkage adjustments), the carburetor could leak fuel or fail to perform as intended. Proper installation knowledge is essential.

6. **Environmental and Emissions Concerns** Older outboards may not meet modern emissions standards if heavily modified with aftermarket carburetors. The NSF5B model is relatively modern, but it s worth verifying compliance if used in regulated areas.

7. **Warranty Considerations** If the outboard is under warranty, replacing the carburetor with an aftermarket part (even a direct replacement) may void certain warranty provisions. Always check with the manufacturer before proceeding.

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### **Conclusion**

The BF&O QUXR70 carburetor is a **strong, reliable upgrade** for Mercury/Toledo 4HP-5HP outboards, particularly the 853720T25 and NSF5B models. Its direct fitment, improved performance, and durability make it a practical choice for boat owners looking to enhance their engine s efficiency and power. However, it requires careful installation and tuning to avoid issues, and it may not be the best option if the engine has been heavily modified or if warranty concerns exist.

For most users seeking a **cost-effective, high-quality replacement** without major engine modifications, the QUXR70 is a **highly recommended choice**. If you are unsure about installation or tuning, consulting a marine mechanic or carburetor specialist is advisable.

Purchase the BF&O QUXR70 carburetor if you need a **direct, reliable replacement** that improves performance and longevity. Ensure proper installation and basic tuning to maximize benefits. If the engine has been significantly modified or if warranty coverage is a concern, weigh the risks carefully before proceeding.

Details:

OE/Part number. Vehicle Service Type: for Marine. 3R1-03200-1, 3AS-03200-0, 3GV-03200-0. 803522T1,803522T2,803522T03,803522T04.

1.Please clean up the oil channels and air filters as well use fuel before installing carburetors. Guaranteed, Fitment Price match Always the correct part. For Mercury Mariner 4-stroke 3.5hp 4hp 5hp 6hp outboard motor, Tohatsu Nissan MF3.5, MFS5, MFS4, MFS4A, MFS4A2, MFS4B, MFS4C, NFS4, NSF4A, NSF4A2, NSF4B, NSF4C, MFS5A, MFS5A2, MFS5B, MFS5C, NSF5A, NSF5A2, NSF5B, NSF5C. Fast Shipping.

Package included. 3.Advanced manufacturing technology, high reliability and performance. Accessories shown as the pictures. 1.Good durability and reliability.

PRODUCT DISPLAY Carburetor Assembly for Mercury Tohatsu 4HP 5HP Outboard 853720T25 NSF5B.

part #: quxr70 prices

• $49.90-$59.80

specifications ouboaen:

• for makes: Mercury
• brand: Bfo
• mpn: Quxr70
• part type: 5hp Carburetor
• california prop 65 warning: California Prop 65 Warning
• country of origin: China
• engine position: Outboard
• fitment: For 4-stroke 4hp 5hp Outboard Motor, For Tohatsu 4-stroke 4hp 5hp, For Mercury 4-stroke 4hp 5hp
• horse power: 4hp, 5hp
• oe/part number: 3r1-03200-1, 3as-03200-0, 3gv-03200-0, 803522t1, 803522t2, 803522t03, 803522t04, 803522t05, 803522t06, 803522a04, 803522t02, 8m0053670, 853720t25, 898103t51, 889246t10
• replace part number: 3r1032001, 3r1-03200-1, 853720t25, 803522t03, Carburetor, Carburettor, Carburetter, Carb, Carby, Outboard Carburetor, Outboard Motor Carburetor, 4 Stroke Outboard Carburetor
• warranty: 2 Year

shipping ouboaen:

• service: Standard
• type: Fixed
• class: Standard
• cost: $0.00
• transit: 5-9 Days

returns ouboaen:

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

general ouboaen:

• Boat Parts > Outboard Engines Components > Oil Systems
• condition: New

offer ouboaen:

• availability: In Stock
• sold: 0
• started: May 24, 2026
• best offers: True
• quantity: 24
• options: Ship-to-home

payments ouboaen:

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

seller ouboaen:

• # reviews: 2467
• rating: 99.6%
• city: Elk Grove Village, Illinois

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