821854T4/821854T5/821854T6 Fuel Pump Assembly for Mercury Mariner 40HP 45HP 55HP 60HP 2-Stroke 3-Cylinder | JLM Marine

Fuel Pump Assembly for Mercury Mariner 40HP 45HP 55HP 60HP 2-Stroke 3-Cylinder

This fuel pump assembly is engineered to fit Mercury Mariner 40HP, 45HP, 55HP, and 60HP 2-stroke 3-cylinder outboard engines. Designed as a direct replacement for critical fuel delivery components, it ensures reliable performance and smooth engine operation.

This assembly directly replaces OEM part numbers 821854T4, 821854T5, and 821854T6, providing a cost-effective aftermarket solution for maintaining your outboard's fuel system.

• Package includes 3 carburetors for complete fuel system coverage
• Direct fit for Mercury Mariner 2-stroke 3-cylinder engines
• Ensures proper fuel delivery and engine performance

Part Number Cross-Reference

Use this table to confirm equivalent part numbers across OEM and aftermarket brands.

Compatible Engine Models

Confirm your engine model/year in the table below. For Mercury owners, here's a guide to help you identify your engine's serial/model: Mercury Serial Number Guide. You can also review exploded diagrams to verify part numbers: Mercury Parts Diagrams & Catalog.

Technical Specifications

Package Contents

• 3 × Carburetors

Installation Guide

1. Disconnect the fuel line from the engine and relieve any residual fuel pressure in the system. Ensure the engine is cool and the battery is disconnected.
2. Remove the engine cover to access the existing carburetors and fuel pump assembly. Take photos for reference during reassembly.
3. Disconnect the throttle linkage, choke cables, and fuel lines from each carburetor. Label each connection to ensure correct reinstallation.
4. Unbolt and remove the old carburetors from the intake manifold. Inspect the mounting gaskets and replace if worn or damaged.
5. Clean the intake manifold surfaces thoroughly to remove old gasket material and debris.
6. Install new gaskets onto the intake manifold mounting surfaces. Ensure they are properly aligned to prevent air leaks.
7. Position each new carburetor onto the intake manifold and secure with mounting bolts. Tighten bolts evenly in a cross pattern to manufacturer specifications.
8. Reconnect fuel lines to each carburetor, ensuring all connections are tight and secure to prevent leaks.
9. Reattach throttle linkage and choke cables to the carburetors, verifying smooth operation of all control mechanisms.
10. Reconnect the battery and fuel supply line. Prime the fuel system by squeezing the primer bulb until firm.
11. Start the engine and check for fuel leaks around all carburetor connections. Allow the engine to warm up and verify smooth idle and throttle response.
12. Adjust idle speed and fuel mixture as needed per manufacturer specifications. Reinstall the engine cover and perform a water test.

Troubleshooting & FAQ

Q: How do I confirm this fuel pump assembly fits my Mercury engine?
A: Verify your engine's horsepower (40HP, 45HP, 55HP, or 60HP), stroke type (2-stroke), and cylinder count (3-cylinder). Cross-reference your original part number with 821854T4, 821854T5, or 821854T6. You can use the Mercury Serial Number Guide or Parts Catalog linked above to confirm compatibility.

Q: What should I do if my engine runs rough after installing the new carburetors?
A: First, check all fuel line connections for leaks or air intrusion. Verify that throttle linkages and choke cables are properly adjusted. If rough running persists, adjust the idle mixture screws and synchronize the carburetors according to your engine's service manual specifications.

Q: How often should I replace or service the carburetors?
A: Carburetors should be inspected and cleaned annually, especially if you use ethanol-blended fuels. Replace carburetors when you experience persistent starting issues, poor fuel economy, or uneven engine performance that cleaning does not resolve. Typical lifespan varies based on fuel quality and maintenance habits.

Q: What are the signs that my fuel pump or carburetors are failing?
A: Common symptoms include hard starting, rough idling, loss of power at high RPM, excessive fuel consumption, fuel leaks, or engine stalling. Black smoke from the exhaust can indicate overly rich fuel mixture from carburetor malfunction.

Q: Is this an OEM part or aftermarket replacement?
A: This listing is an aftermarket replacement part (not an OEM component). We build to OEM specifications using comparable-grade materials. Production is done in an ISO9002-certified facility, and each batch is inspected for consistent performance.

Q: How fast do you ship and how much does it cost?
A: We offer fast global shipping—typically 5–15 days worldwide—and standard shipping is free. Expedited options are available at checkout depending on your location.

Q: What is your warranty and return policy?
A: This product includes a 1-year warranty against manufacturing defects under normal use. If something goes wrong, contact our support team with your order details. Returns are accepted within our standard return window (unused & in original condition); please see our policy page or reach out for instructions.

Important Notes

• Verify that the product images and specifications match your original part. If discrepancies exist—even if your model is listed—do not proceed with the purchase.
• This product is an aftermarket replacement part and is not an OEM component.
• Professional installation is recommended to ensure safety and optimal performance.

Why Choose JLM MARINE?

• Quality Assured: As a trusted manufacturer for over 20 years, we supply top marine brands globally.
• Fast Global Shipping: Free delivery worldwide in 5–15 days.
• Direct from Manufacturer: Competitive pricing without compromising quality.