Fuel Filter Element – Fits Mercury/Mariner 6-70 HP (Replaces 35-87946A3, 35-87946Q04)
Fuel Filter Element – Fits Mercury/Mariner 6-70 HP (Replaces 35-87946A3, 35-87946Q04) is backordered and will ship as soon as it is back in stock.
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Delivery and Shipping
Delivery and Shipping
Free standard shipping on all orders under 1 KG
Fuel Filter Element – Fits Mercury/Mariner 6-70 HP (Replaces 35-879...
Product Details
This replacement Fuel Filter Element – Fits Mercury/Mariner 6-70 HP (Replaces 35-87946A3, 35-87946Q04) is designed to protect your engine by removing contaminants from the fuel supply. It is engineered for a broad range of Mercury/Mariner 2-stroke and 4-stroke outboard engines from 6 to 70 HP, generally covering models from the 1990s to the 2010s. It is also compatible with select Suzuki models that specify part number 15430-87D10.
This part provides a direct interchange for Sierra 18-7802, Fram P8263, Wix 33398, Mercury 35-87946A3, 35-87946Q04, 35-87946Q3, and 87946T3, as well as Suzuki 15430-87D10.
- Installs within the under-cowl fuel filter housing that uses a screw-on bowl.
- Includes a new Viton O-ring for a reliable seal upon installation.
- Filters gasoline to between 75 and 149 microns, depending on the manufacturing batch.
Part Number Matrix
Use this matrix to confirm equivalent references across OEM and aftermarket brands.
| Brand | Part Number |
|---|---|
| Mercury | 35-87946A3 |
| Mercury | 35-87946Q04 |
| Mercury | 35-87946Q3 |
| Mercury | 87946T3 |
| Suzuki | 15430-87D10 |
| Sierra | 18-7802 |
| Fram | P8263 |
| Wix | 33398 |
Engine & Model Compatibility
Confirm your engine model and year in the table below. If you are uncertain, please verify the part number from your service manual or existing filter.
For Mercury/Mariner owners: This filter fits a wide array of 2-stroke and 4-stroke outboards from 6 to 70 HP. Cross-reference your engine's horsepower and stroke type to ensure compatibility.
For Suzuki owners: Fitment is based on the OEM part number 15430-87D10. Ensure your engine model calls for this specific part.
| Brand | Model | Rated HP | Stroke | OEM Part No. | Notes |
|---|---|---|---|---|---|
| Mercury/Mariner | Outboard | 6 | 2-Stroke | 35-87946A3 | |
| Mercury/Mariner | Outboard | 8 | 2-Stroke | 35-87946A3 | |
| Mercury/Mariner | Outboard | 9.9 | 2-Stroke & 4-Stroke | 35-87946A3 | |
| Mercury/Mariner | Outboard | 10 | 2-Stroke | 35-87946A3 | |
| Mercury/Mariner | Outboard | 13.5 | 2-Stroke | 35-87946A3 | |
| Mercury/Mariner | Outboard | 15 | 2-Stroke & 4-Stroke | 35-87946A3 | |
| Mercury/Mariner | Outboard | 20 | 2-Stroke | 35-87946A3 | |
| Mercury/Mariner | Outboard | 25 | 2-Stroke & 4-Stroke | 35-87946A3 | |
| Mercury/Mariner | Outboard | 45 | 4-Stroke | 35-87946A3 | |
| Mercury/Mariner | Outboard | 50 | 2-Stroke & 4-Stroke | 35-87946A3 | |
| Mercury/Mariner | Outboard | 70 | 4-Stroke | 35-87946A3 |
Technical Specs
- Product Type
- Fuel Filter Element with O-Ring
- Installation
- Under-cowl fuel filter housing with screw-on bowl
- Filtration Rating
- 75-149 microns (sources vary)
- Fuel Type
- Gasoline
- Weight
- Approx. 0.02 kg (0.044 lb)
- Warranty
- 1 Year (when branded as UANOFCN)
- Other Technical Attributes
- Includes Viton seal for filter housing
What’s in the Box
- 1 x Fuel Filter Element with O-Ring
Installation Notes
- Turn off the engine and disconnect the battery.
- Place an absorbent rag under the fuel filter housing to catch any spilled fuel. Ensure the area is well-ventilated.
- Carefully unscrew the clear plastic bowl from the filter housing.
- Remove the old filter element and the o-ring seal from the housing or bowl.
- Clean the inside of the bowl with a lint-free cloth, removing any sediment or debris.
- Install the new filter element into the housing.
- Lightly lubricate the new o-ring with clean motor oil and place it correctly in its groove.
- Securely screw the bowl back onto the housing by hand until snug. Do not overtighten.
- Reconnect the battery.
- Prime the fuel system using the primer bulb until firm.
- Start the engine and carefully inspect the filter assembly for any leaks.
Troubleshooting & FAQ
How do I confirm this filter fits my specific engine model and year?
The most reliable method is to check your engine's service manual for the recommended OEM part number. If it matches any of the numbers in our Part Number Matrix (e.g., Mercury 35-87946A3, Suzuki 15430-87D10), this filter is a compatible replacement. While our tables cover most applications, OEM part-number matching is the definitive check.
What are the signs of a clogged or failing fuel filter?
Common symptoms include engine hesitation or sputtering, difficulty starting, rough idling, reduced power, or stalling, especially under load. If you notice these issues, a clogged fuel filter is a likely cause and should be inspected.
How often should I replace this fuel filter?
For preventative maintenance, it is best practice to replace your fuel filter annually or every 100 hours of operation, whichever comes first. If you frequently use fuel from questionable sources or notice performance issues, you may need to replace it more often.
Your specs mention 75-149 microns. Which is it?
Different aftermarket manufacturers and suppliers report slightly different specifications for the same cross-referenced part. Both 75 and 149 microns are within the acceptable range for this type of under-cowl outboard fuel filter, effectively protecting carburetors and injectors from harmful debris without restricting flow.
Is the O-ring/gasket included with the filter?
Yes, this kit includes the required Viton O-ring for the filter bowl, ensuring you have everything needed for a leak-free replacement.
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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