In-line Fuel Filter – Fits Mercury/Mariner 30-350 HP EFI (Replaces 35-879885Q, 35-879885T, 35-879885K)

$14.99

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In-line Fuel Filter – Fits Mercury/Mariner 30-350 HP EFI (Replaces 35-879885Q, 35-879885T, 35-879885K) is backordered and will ship as soon as it is back in stock.

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Product Details

This In-line Fuel Filter – Fits Mercury/Mariner 30-350 HP EFI Outboards (Replaces 35-879885Q, 35-879885T, 35-879885K) is designed for a wide range of Mercury and Mariner 4-Stroke outboards from 30 to 350 HP, including EFI and Verado models manufactured from 1996 and newer. It also fits select Yamaha 2-Stroke and 4-Stroke outboards from 1984 onwards, ensuring broad compatibility for under-cowl fuel systems.

It serves as a direct replacement for Mercury parts 35-879885Q, 35-879885T, 35-879885K, Sierra 18-7718, and Yamaha 6G1-13621 series numbers, offering a reliable aftermarket alternative.

Installs in-line under the engine cowl.
Features a 20–30 micron filtration rating to protect sensitive engine components.
Constructed with sonically sealed end caps and approved for use with ethanol-blended fuels like E10.

Part Number Matrix

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

Brand	Part Number
Mercury	35-879885Q
Mercury	35-879885T
Mercury	35-879885K
Mercury	27-11471M
Sierra	18-7718
Yamaha	6G1-13621-A1-00
Yamaha	6G1-13621-00-00
Aftermarket	AM6G1-13621-A1

Engine & Model Compatibility

Confirm your engine model/year in the table below.

For Mercury/Mariner owners: This filter fits a wide array of 4-Stroke models from 1996 and newer, including EFI, Verado, and Jet Drive applications. Check your serial number (S/N) for specific 75-150 HP models.

Brand	Model	Rated HP	Stroke	Years	OEM Part No.	Notes
Mercury	EFI FourStroke	30, 40	4-Stroke	1996 and newer	35-879885Q/T/K	Under-cowl installation
Mercury	FourStroke (996cc)	40, 50, 60	4-Stroke	1996 and newer	35-879885Q/T/K	4-cylinder models
Mercury	FourStroke 1.7L	75-115	4-Stroke	S/N 1B366823-2B094995	35-879885Q/T/K
Mercury	FourStroke 2.1L	75-115	4-Stroke	S/N 2B094996 and above	35-879885Q/T/K
Mercury	EFI FourStroke	150	4-Stroke	S/N 1B905505 and above	35-879885Q/T/K
Mercury	Verado	135-300	4-Stroke	2004 and newer	35-879885Q/T/K
Mercury	Verado Pro	200-300	4-Stroke	2004 and newer	35-879885Q/T/K
Mercury	Verado	350-400	4-Stroke	2004 and newer	35-879885Q/T/K
Mercury	EFI	65, 80	4-Stroke	1996 and newer	35-879885Q/T/K	Jet drive models
Mariner	Outboards	30-300	4-Stroke	1996 and newer	35-879885Q/T/K

For Yamaha owners: Compatibility extends to various 2-Stroke models from 1984 and newer. Verify against your engine's OEM part number.

Brand	Model	Rated HP	Stroke	Years	OEM Part No.	Notes
Yamaha	6C/6D/6MH/6CMH/6DMH/6TRV	2-90	2-Stroke	1984 and newer	6G1-13621-00-00

Technical Specs

Product Type: In-Line Fuel Filter
Installation: Under-cowl, in-line
Filtration Rating: 20–30 micron
Fuel Type: Gasoline, ethanol blends (e.g., E10)
Connection: 8mm fuel line
Housing Material: Translucent plastic
Housing Color: Clear
Weight: 0.08 kg (2.89 oz)
Fitting Type: Push-on barb connection
Warranty: 1-year against manufacturing defects (aftermarket versions)
Other Technical Attributes: Sonically sealed end caps; approved for use with ethanol-based fuels

What’s in the Box

1 x In-Line Fuel Filter (Replaces 35-879885Q, 35-879885T, 35-879885K)

Installation Notes

Turn off the engine and allow it to cool completely. Ensure the area is well-ventilated.
Locate the existing in-line fuel filter under the engine cowling.
Place a shop towel or container under the filter to catch any spilled fuel.
Carefully loosen the clamps and disconnect the fuel hoses from both ends of the old filter. Note the direction of the fuel flow arrow.
Remove the old filter from its mounting bracket or position.
Install the new filter, ensuring the fuel flow arrow points in the correct direction (towards the engine).
Securely attach the fuel hoses to the new filter and tighten the clamps. Do not overtighten.
Prime the fuel system according to your engine manufacturer's instructions.
Start the engine and carefully inspect the filter and connections for any leaks.

Troubleshooting & FAQ

How often should I replace this fuel filter?

For optimal engine performance and protection, it is recommended to replace your in-line fuel filter annually or every 100 hours of operation, whichever comes first. Refer to your engine's service manual for manufacturer-specific intervals.

What are the signs of a clogged or failing fuel filter?

Common symptoms include engine hesitation or sputtering, difficulty starting, rough idling, reduced horsepower, and stalling, especially under load. A visual inspection of the clear housing may also show sediment or debris.

Is this filter compatible with ethanol-blended fuels like E10?

Yes, this fuel filter is constructed with materials that are fully compatible with modern gasoline and ethanol blends up to E10. The end caps are sonically sealed to prevent leaks.

How can I be sure this filter will fit my specific engine?

First, check the Part Number Matrix to see if your existing filter's part number is listed. Second, consult the Engine & Model Compatibility tables. Pay close attention to HP, year, stroke, and any serial number (S/N) ranges to confirm a match.

Is there a difference between this and the OEM filter?

This aftermarket filter is designed to meet or exceed OEM specifications for fit, form, and function. It provides the same level of filtration and fuel compatibility as the original part but at a more competitive price point.

OEM vs. Aftermarket?

This listing is an aftermarket replacement (not OEM). Built to OEM-level specifications with comparable materials. Manufactured in an ISO 9002 facility, batch-inspected for consistency.

Shipping speed & cost

We ship worldwide quickly—typical transit 5–15 days. Standard shipping is free; expedited options appear at checkout where available.

Warranty & returns

Covered by a 1-year warranty against manufacturing defects under normal use. If issues arise, contact support with your order details. Returns are accepted within our standard window (unused & in original condition). See our policy page or reach out for instructions.

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.

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