Inline Fuel Filter – Fits MerCruiser Sterndrive & Inboard Gasoline Engines (Replaces 35-864572)
Inline Fuel Filter – Fits MerCruiser Sterndrive & Inboard Gasoline Engines (Replaces 35-864572) is backordered and will ship as soon as it is back in stock.
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Worry-free returns
Worry-free returns
You may return most new, unopened items within 7 days of delivery for a full refund. We'll also pay the return shipping costs if the return is a result of our error (you received an incorrect or defective item, etc.).
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Delivery and Shipping
Delivery and Shipping
Free standard shipping on all orders under 1 KG
Inline Fuel Filter – Fits MerCruiser Sterndrive & Inboard Gasol...
Product Details
This replacement inline fuel filter is engineered for MerCruiser sterndrive and inboard gasoline engines that are equipped with a fuel booster pump. It installs between the fuel tank and the booster pump to protect the system by preventing debris from reaching the boost pump inlet, ensuring clean fuel delivery and reliable engine performance.
This part is a direct interchange for Mercury/Quicksilver part numbers 864572, 35-864572, 35-864572T, 35-864572T01, and Sierra 18-7721.
- Installs inline between the fuel tank and fuel booster pump.
- Protects the fuel system from contaminants.
- Designed as a direct-fit aftermarket replacement.
Part Number Matrix
Use this matrix to confirm equivalent references across OEM and aftermarket.
| Brand | Part Number |
|---|---|
| Mercury/Quicksilver | 864572 |
| Mercury/Quicksilver | 35-864572 |
| Mercury/Quicksilver | 35-864572T |
| Mercury/Quicksilver | 35-864572T01 |
| Sierra | 18-7721 |
Engine & Model Compatibility
Confirm your engine model/year in the table below.
This filter is designed for all MerCruiser sterndrive and inboard gasoline engines equipped with a fuel booster pump.
| Brand | Model | Rated HP | Stroke | OEM Part No. | Notes |
|---|---|---|---|---|---|
| MerCruiser | All sterndrive and inboard gasoline engines with boost pump | Various | 4-Stroke | 35-864572 | |
| MerCruiser | 8.1L & 496 CID | Various | 4-Stroke | 35-864572 | Specifically mentioned for Sierra 18-7721 |
| MerCruiser | MPI & EFI engines with boost pump | Various | 4-Stroke | 35-864572 | Specifically mentioned for Sierra 18-7721 |
Technical Specs
- Product Type
- Inline Fuel Filter
- Installation
- Between fuel tank and booster pump
- Filtration Rating
- 180 micron (Sierra equivalent)
- Fuel Type
- Gasoline
- Connection
- 3/8" I.D. Fuel Lines
- Housing Material
- Stainless Steel
- Dimensions
- 13.0 × 7.0 × 7.0 in
- Weight
- 0.27 kg (0.6 lb)
- Fitting Type
- Inline
- Warranty
- Limited lifetime (Sierra aftermarket equivalent)
- Other Technical Attributes
- Designed to meet OEM specifications
What’s in the Box
- 1 x Inline Fuel Filter (35-864572)
Installation Notes
- Ensure the engine is off and cool. Relieve fuel system pressure according to your engine's service manual.
- Locate the existing fuel filter between the fuel tank and the booster pump.
- Place a catch pan under the filter to collect any spilled fuel.
- Carefully loosen the hose clamps and disconnect the fuel lines from the old filter.
- Remove the old filter from its mounting bracket, if applicable.
- Note the direction of fuel flow indicated on the new filter.
- Install the new filter, ensuring the flow arrow points toward the engine's booster pump.
- Securely attach and tighten the fuel lines and clamps.
- Prime the fuel system as per the manufacturer's instructions.
- Start the engine and check for any leaks.
Troubleshooting & FAQ
Where is this filter installed?
This inline fuel filter must be installed on the fuel line between the fuel tank and the electric fuel booster pump. Correct placement is critical for protecting the pump from debris.
What are the signs of a clogged fuel filter?
Common symptoms of a failing or clogged filter include engine hesitation, sputtering at high speeds, loss of power, difficulty starting, or stalling. If you experience these issues, inspect the fuel filter as a potential cause.
Is this filter for gasoline or diesel engines?
This filter is designed exclusively for use with gasoline engines. Do not use it in diesel applications, as it does not provide the water separation or filtration level required for diesel fuel systems.
How often should this fuel filter be replaced?
Replacement intervals can vary based on fuel quality and usage. It is best to follow the replacement schedule in your engine's service manual. As a general guideline, consider inspection or replacement annually or every 100 hours of operation.
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.
Payment & Security
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