Fuel Filter Assembly – Fits Mercury/Mariner 30-60 HP 4-Stroke Outboards (Replaces 35-879884T, 879884T)

Fuel Filter Assembly – Fits Mercury/Mariner 30-60 HP 4-Stroke Outboards

This fuel filter assembly is designed for use on Mercury and Mariner 30-60 HP EFI 4-stroke, 3 & 4-cylinder outboard engines that feature a screw-on type filter bowl mounted under the cowl.

It serves as a direct replacement for Mercury/Mariner part numbers: 35-879884T, 879884T, 879884.

• Installation Location: Under-cowl, inline
• Filtration Performance: Filters contaminants down to 20 microns
• Clear Housing: Features a translucent bowl to easily monitor fuel content and trapped debris

Part Number Cross-Reference

Use this table to confirm equivalent part numbers.

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

1 x Cartridge Fuel Filter Assembly (35-879884T)

Installation Guide

1. Ensure the engine is turned off and has cooled down completely.
2. Locate the existing fuel filter assembly, typically found under the engine cowl.
3. Place a suitable container or absorbent rag underneath the filter to catch any fuel spillage.
4. Carefully disconnect the fuel lines attached to both sides of the filter, noting their orientation.
5. Unscrew and remove the old filter assembly from its mounting location.
6. Compare the new filter with the old one to confirm the fit is identical.
7. Install the new filter assembly, making sure the bowl is screwed on securely.
8. Reconnect the fuel lines to the correct inlet and outlet ports on the new filter.
9. Prime the fuel system as outlined in your outboard's service manual to fill the new filter with fuel.
10. After priming, thoroughly inspect the filter and all connections for any signs of fuel leaks.
11. Start the engine and let it run for a few minutes while checking for leaks and ensuring smooth operation.

Troubleshooting & FAQ

Q: How do I confirm this filter fits my Mercury engine?

A: This filter fits specific 30-60 HP EFI 4-stroke Mercury and Mariner outboards. The most reliable way to confirm fitment is to match the part number (35-879884T) and check your engine's serial number against the ranges provided in the "Compatible Engine Models" table. For additional help, you can use our Mercury Serial Number Guide.

Q: How can I tell if the filter needs to be replaced?

A: This assembly includes a translucent bowl, which allows for easy visual inspection. If you see water (which will separate from the fuel), significant debris, or rust particles, it is time to replace the filter. It should also be replaced as part of your engine's regular annual service schedule.

Q: What are the common symptoms of a clogged or failing fuel filter?

A: A restricted fuel filter can cause symptoms such as engine hesitation, loss of power, difficulty starting, rough idling, or engine stalls, particularly at high speeds or under load.

Q: What is the filtration rating of this fuel filter?

A: It has a filtration rating of 20 microns, which is designed to effectively capture harmful contaminants before they can reach the sensitive components of your engine's fuel system.

Q: OEM vs. Aftermarket?

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.