Oil Filter – Fits MerCruiser D7.3L D-Tronic Diesel Engines (Replaces 35-805809)
Oil Filter – Fits MerCruiser D7.3L D-Tronic Diesel Engines (Replaces 35-805809) is backordered and will ship as soon as it is back in stock.
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Oil Filter – Fits MerCruiser D7.3L D-Tronic Diesel Engines (Replaces 35-805809) is backordered and will ship as soon as it is back in stock.
Product Details
This aftermarket Oil Filter – Fits MerCruiser D7.3L D-Tronic Diesel Engines is designed for reliable performance in 4-stroke marine diesel applications. It is engineered for MerCruiser 7.3L engines from 1999 and compatible model years, ensuring proper filtration and engine protection.
It serves as a direct replacement for Mercury part number 35-805809.
- Installation Method: Spin-on
- Special Instruction: Hand-tighten only; do not use a filter wrench.
- Package Contents: One oil filter.
Part Number Matrix
Use this matrix to confirm equivalent references across OEM and aftermarket.
| Brand | Part Number |
|---|---|
| Mercury | 35-805809 |
Engine & Model Compatibility
Confirm your engine model/year in the table below.
| Brand | Model | Rated HP | Stroke | Years | OEM Part No. | Notes |
|---|---|---|---|---|---|---|
| MerCruiser | D7.3L D-Tronic | 300 | 4-Stroke | 1999 | 35-805809 | Pleasure duty rating |
| MerCruiser | D7.3L D-Tronic LD | 260 | 4-Stroke | 1999 | 35-805809 | Light duty rating |
Technical Specs
- Product Type
- Engine Oil Filter
- Installation
- Spin-on
- Fuel Type
- Diesel
- Connection
- Threaded
- Fitting Type
- Threaded
- Product Dimensions
- Height: 12.0; Width: 11.5; Length: 16.5
- Technical Note
- Hand-tighten only, do not use filter wrench
What’s in the Box
- 1 x Oil Filter (Replaces 35-805809)
Installation Notes
- Ensure the engine is cool and place an oil drip pan under the old filter.
- Unscrew the old filter counter-clockwise. Be prepared for some residual oil to spill.
- Clean the filter mounting base on the engine, ensuring the old gasket is completely removed.
- Apply a thin film of new engine oil to the gasket of the new filter.
- Carefully screw the new filter onto the threaded mount until the gasket makes firm contact with the base.
- Hand-tighten the filter only. Per manufacturer specifications, do not use a filter wrench to tighten, as this can damage the filter or seal.
- After installation, run the engine for a few minutes and check for leaks around the filter.
- Stop the engine, re-check the oil level, and top off as needed.
Troubleshooting & FAQ
Will this filter fit a MerCruiser D7.3L from a year other than 1999?
This filter is confirmed for 1999 MerCruiser D7.3L D-Tronic engines and is designed for compatible model years. To ensure a perfect match, always verify that your engine's service manual specifies OEM part number 35-805809.
Is a special tool required to install this filter?
No. This filter is designed to be hand-tightened only. Using a filter wrench for tightening can lead to over-torquing and damage the filter seal or housing. A wrench should only be used for removal if needed.
How often should this oil filter be replaced?
The replacement interval depends on engine hours and operating conditions. Always follow the maintenance schedule recommended by your engine manufacturer, which typically involves changing the oil and filter at least once per season or every 100 hours of operation.
What are the signs of a failing oil filter?
Symptoms of a clogged or failing oil filter can include a drop in engine performance, inconsistent oil pressure readings, or engine oil that appears unusually dirty shortly after a change. Regular replacement during scheduled service is the best way to prevent issues.
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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