Mercury 225 HP Oil & Filter Change
Fresh oil and a new filter are the cheapest insurance for your 225 hp Mercury 225 HP. Below is the oil filter we recommend, which 225 HP variants it fits, a step-by-step video of the full oil change, and what else you need for the job.
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Which part do I need for my Mercury 225 HP?
For most 225 HP owners the part above (18-7906-1) is the right choice. Price tip: the aftermarket numbers are usually noticeably cheaper than the OEM-branded box — it is the same physical part. If you need an exact match, these compatible part numbers also fit:
Show all compatible part numbers (4)
| Part number | Description | Fits | |
|---|---|---|---|
| 18-7918 | OIL FILTER | 225 | Find on Amazon → |
| 35822626Q15 | Mercury OEM 35822626Q15 (replaces Sierra 18-7906-1) | 225 FourStroke, EFI, 225, FourStroke, 3.4L V6, 225, FourStroke, 4.6L V8 PRO XS and 3 more rigging variants | Find on Amazon → |
| 822626Q15 | Mercury OEM 822626Q15 (replaces Sierra 18-7906-1) | 225 FourStroke, EFI, 225, FourStroke, 3.4L V6, 225, FourStroke, 4.6L V8 PRO XS and 3 more rigging variants | Find on Amazon → |
| 822626T7 | Mercury OEM 822626T7 (replaces Sierra 18-7906-1) | 225 FourStroke, EFI, 225, FourStroke, 3.4L V6, 225, FourStroke, 4.6L V8 PRO XS and 3 more rigging variants | Find on Amazon → |
Many of these are the same physical part under different brand numbers. Build years are shown where our parts data has them. Where a variant has no years, only the model code is listed. Confirm against your engine plate before ordering.
Frequently asked questions
What oil filter fits a Mercury 225 HP (225 hp)?
The Mercury 225 HP uses the oil filter sold as Sierra 18-7906-1, plus its OEM and aftermarket cross-references (4 compatible numbers are listed above). Confirm the number against your engine's model code and year plate before ordering.
How often should I replace the oil filter on a Mercury 225 HP?
Change the oil and filter every 100 running hours or once a season, whichever comes first (check your manual for the exact interval).
What else do I need for an oil change on a Mercury 225 HP?
The correct grade and amount of engine oil (see the manual or the video), a new drain-plug washer, a filter wrench and a drain pan or oil extractor pump. Nothing exotic — it is standard service equipment.
What are the signs the oil is overdue on a Mercury 225 HP?
Dark, gritty oil well past its interval, low-pressure warnings — and milky or grey oil, which means water is getting in and should be investigated immediately.
How long does an oil change take on a Mercury 225 HP?
About an hour for a competent DIYer. Run the engine warm first — warm oil drains faster and carries more contaminants out with it.
Related guides
- Mercury 50 HP oil filter
- Mercury 75 HP oil filter
- Mercury 25 HP oil filter
- Mercury 90 HP oil filter
- All Mercury maintenance guides
- Free Mercury boat valuation
- Buying a boat? Check whether the asking price is fair
As an Amazon Associate we earn from qualifying purchases — at no extra cost to you. Prices and availability are shown at checkout. This guide is for reference; always follow the engine manufacturer’s service manual.