Fuel Filter – Fits MerCruiser Sterndrive & Inboard Gasoline Engines (Replaces 35-864572, 35-864572T, 35-864572T01)
Fuel Filter – Fits MerCruiser Sterndrive & Inboard Gasoline Engines (Replaces 35-864572, 35-864572T, 35-864572T01) 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.).
You should expect to receive your refund within four weeks of giving your package to the return shipper, however, in many cases you will receive a refund more quickly. This time period includes the transit time for us to receive your return from the shipper (5 to 10 business days), the time it takes us to process your return once we receive it (3 to 5 business days), and the time it takes your bank to process our refund request (5 to 10 business days).
If you need to return an item, simply login to your account, view the order using the "Complete Orders" link under the My Account menu and click the Return Item(s) button. We'll notify you via e-mail of your refund once we've received and processed the returned item.
Delivery and Shipping
Delivery and Shipping
Free standard shipping on all orders under 1 KG
Product Details
This In-Line Fuel Filter is a direct replacement for MerCruiser sterndrive and inboard gasoline engines that utilize a boost pump. It is engineered for a wide range of models, including 350, 357, 383, 385, 409, 496 series, as well as 5.0L, 6.2L, and 8.1L engines, ensuring reliable fuel purification.
Serves as a direct replacement for MerCruiser part numbers 35-864572, 35-864572T, and 35-864572T01, and interchanges with Sierra 18-7721.
- Installs between the fuel tank and the boost pump.
- Effectively filters gasoline down to a 10-micron rating.
- Designed for a secure connection with 3/8" I.D. fuel lines.
Part Number Matrix
Use this matrix to confirm equivalent references across OEM and aftermarket.
| Brand | Part Number |
|---|---|
| MerCruiser | 35-864572 |
| MerCruiser | 35-864572T |
| MerCruiser | 35-864572T01 |
| Sierra | 18-7721 |
Engine & Model Compatibility
Confirm your engine model/year in the table below.
This filter is designed for the specified MerCruiser gasoline engine models equipped with a fuel boost pump.
| Brand | Model | Stroke | Years | OEM Part No. | Notes |
|---|---|---|---|---|---|
| MerCruiser | 5.0L MPI | 4-Stroke | 35-864572 | ||
| MerCruiser | 350 MAG MPI | 4-Stroke | 35-864572 | ||
| MerCruiser | 350 MAG MPI Horizon | 4-Stroke | 2000+ | 35-864572 | |
| MerCruiser | MX 6.2L MPI | 4-Stroke | 35-864572 | ||
| MerCruiser | 6.2L MPI Horizon | 4-Stroke | 35-864572 | ||
| MerCruiser | 357 Horizon Bobtail | 4-Stroke | 35-864572 | ||
| MerCruiser | 383 MPI Bravo | 4-Stroke | 35-864572 | ||
| MerCruiser | 5.7L MPI Alpha | 4-Stroke | 35-864572 | ||
| MerCruiser | 5.7L MPI Bravo | 4-Stroke | 35-864572 | ||
| MerCruiser | 5.7L MAG MPI SKI | 4-Stroke | 35-864572 | Serial #0W690000 - 1A089999 | |
| MerCruiser | 8.1L | 4-Stroke | 35-864572 | ||
| MerCruiser | 496 MAG | 4-Stroke | 35-864572 |
Technical Specs
- Product Type
- Inline Fuel Filter
- Installation
- Between fuel tank and boost pump
- Filtration Rating
- 10 micron
- Fuel Type
- Gasoline
- Connection
- 3/8" I.D. fuel line
- Housing Color
- Silver/Metal
- Other Technical Attributes
- Over 90% efficient at removing 10-micron and larger particles
What’s in the Box
- 1x In-Line Fuel Filter
Installation Notes
- Ensure the engine is off and cool. Disconnect the boat's battery for safety.
- Work in a well-ventilated area and have a fire extinguisher nearby.
- Locate the existing in-line fuel filter, typically situated in the fuel line between the fuel tank and the electric boost pump.
- Place a rag or container under the filter to catch any spilled fuel.
- Loosen the clamps on both ends of the old filter and carefully remove it, noting the direction of the flow arrow printed on the housing.
- Install the new filter, making sure the flow arrow points in the same direction (towards the engine/boost pump).
- Securely tighten the fuel line clamps on both ends of the new filter.
- Reconnect the battery.
- Prime the fuel system according to your engine's manual, then start the engine and carefully inspect the filter and connections for any leaks.
Troubleshooting & FAQ
How do I know if this fuel filter fits my engine?
This filter is designed for a broad range of MerCruiser gasoline sterndrive and inboard engines with a boost pump. The most reliable method is to cross-reference your existing filter's part number with the numbers listed in our Part Number Matrix (e.g., 35-864572, 35-864572T). Also, check the Engine & Model Compatibility table and verify your engine model is listed.
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 engine stalling, especially under load. If you experience these issues, a restricted fuel filter is a likely cause.
How often should I replace my inline fuel filter?
For preventative maintenance, it is recommended to replace your fuel filter annually or every 100 hours of operation, whichever comes first. Refer to your engine's service manual for the specific maintenance schedule.
Where is this filter installed?
This in-line fuel filter is installed in the fuel line between the boat's fuel tank and the electric fuel boost pump.
Is this a genuine MerCruiser part?
This is an aftermarket replacement part, not an OEM component. It has been manufactured to meet or exceed OEM specifications for fit, form, and function, providing a reliable and cost-effective alternative.
What is the difference between OEM and aftermarket parts?
This listing is an aftermarket replacement (not OEM). It's built to OEM-level specifications with comparable materials. The part is manufactured in an ISO 9001 certified facility and is batch-inspected to ensure quality and consistency.
What are your shipping speed and cost?
We ship worldwide quickly—typical transit is 5–15 days. Standard shipping is free; expedited options appear at checkout where available.
What is your warranty and return policy?
This product is covered by a 1-year warranty against manufacturing defects under normal use. If issues arise, contact our support team with your order details. Returns are accepted within our standard window for items that are unused and in their 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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