Fuel Filter – Fits Mercury/Mariner Outboards 30–300 HP (Replaces 35-879885T, 35-879885Q)

Product Details

This high-quality inline Fuel Filter is designed for a wide range of Mercury and Mariner outboard engines from 30 to 300 HP. It fits 3 & 4-cylinder 4-Stroke EFI models (30–115 HP, 2000–present) and Verado 4-cylinder (135–200 HP) and 6-cylinder (200–400 HP) models, ensuring your engine is protected from contaminants.

This filter is a direct replacement for multiple part numbers, including Mercury/Quicksilver 35-879885T and 35-879885Q, Sierra 18-7718, and others, offering a reliable aftermarket alternative.

• Installs in-line with the fuel system. Recommended to be purchased in multiples of two.
• Features a clear plastic housing for visual inspection of fuel flow and contaminants.
• Equipped with push-on 8mm (5/16") hose barb connectors for easy installation.

Part Number Matrix

Use this matrix to confirm equivalent references across OEM and aftermarket.

Engine & Model Compatibility

Confirm your engine model/year in the table below.

Technical Specs

Product Type

Inline Fuel Filter

Installation

In-line; must be sold in multiples of 2

Fuel Type

Gasoline

Connection

8mm (5/16") hose connector

Housing Material

Plastic

Housing Color

Clear/White

Dimensions

9.0" L × 8.0" W × 8.0" H

Weight

0.08 kg (0.18 lb)

Fitting Type

Push-on hose barb

Warranty

OEM/Manufacturer warranty

Other Technical Attributes

Designed for Mercury Verado and EFI 4-stroke outboard applications

What’s in the Box

• 1 x Fuel Filter (Replaces 35-879885Q/35-879885T)

Installation Notes

1. Shut off the fuel supply to the engine and disconnect the battery for safety.
2. Locate the existing fuel filter. It is typically in the fuel line between the tank and the engine.
3. Place a rag or small container under the filter to catch any fuel that may spill.
4. Carefully loosen the clamps securing the fuel hoses to both ends of the old filter.
5. Gently twist and pull the hoses off the filter. Be prepared for minor fuel leakage. Note the flow direction arrow on the old filter.
6. Position the new filter, ensuring the fuel flow arrow points towards the engine.
7. Attach the fuel hoses to the new filter and secure them firmly with the clamps.
8. Reconnect the battery and restore the fuel supply.
9. Prime the fuel system according to your engine’s manual, and carefully inspect for any leaks around the filter and connections before starting the engine.

Troubleshooting & FAQ

Safety & Important Info

• Verify images/specifications vs your original part. If anything differs—even if your model appears compatible—do not purchase.
• This is an aftermarket replacement, not an OEM component.
• Professional installation is recommended for safety and performance.

About Sea Sierra

• Pro-Grade Standards — We supply marine parts engineered to OEM-level tolerances and tested for real-world conditions.
• Fast Global Fulfillment — Free standard delivery to most regions in 5–15 days.
• Manufacturer-Direct Value — Fair pricing without compromising on materials or QC.