Mercury 75 HP Oil & Filter Change
Fresh oil and a new filter are the cheapest insurance for your 75 hp Mercury 75 HP. Below is the exact oil filter that fits, a step-by-step video of the full oil change, and what else you need for the job.
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Watch: how to do it (step by step)
How to Replace Oil Filter – Mercury 115
Oil and Filter Change on a Mercury 75-115hp FourStroke Outboards
Tools Needed
- Filter wrench
- 5/8 inch socket and ratchet
Safety
- Ensure motor is cool before starting procedure to avoid burns.
- Be cautious when handling oil to prevent spills.
Steps
- Trim the outboard motor to its full up position to drain oil from the sump.
- Remove the oil cap and locate the drain plug.
- Loosen the drain plug using a 5/8 inch socket and ratchet, then use a hose to catch draining oil.
- Once drained, remove the plastic tube, wipe excess oil, and tighten the drain plug by hand before fully securing it with the ratchet.
- Use a filter wrench to loosen and remove the old oil filter, catching any excess oil with a rag.
- Clean the filter area, apply clean oil to the new filter's seal, and install the new oil filter by hand until it's snug.
- Wipe the dipstick clean, then add fresh oil while monitoring the level on the dipstick.
Tips
- Allow the motor to sit with the drain plug removed for about a minute to ensure all old oil drains out.
- Use your finger to apply a thin film of clean oil around the new filter's seal before installation.
Which part do I need for my Mercury 75 HP?
For most 75 HP owners the part above (18-7914) 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 (6)
| Part number | Description | |
|---|---|---|
| 358M0065103 | Mercury OEM 358M0065103 (replaces Sierra 18-7914) | Find on Amazon → |
| 358M0065104 | Mercury OEM 358M0065104 (replaces Sierra 18-7914) | Find on Amazon → |
| 8M0065103 | Mercury OEM 8M0065103 (replaces Sierra 18-7914) | Find on Amazon → |
| 8M0065104 | Mercury OEM 8M0065104 (replaces Sierra 18-7914) | Find on Amazon → |
| 8M0162829 | Mercury OEM 8M0162829 (replaces Sierra 18-7914) | Find on Amazon → |
| 8M0162830 | Mercury OEM 8M0162830 (replaces Sierra 18-7914) | Find on Amazon → |
Many of these are the same physical part under different brand numbers. Confirm against your engine plate before ordering.
Frequently asked questions
What oil filter fits a Mercury 75 HP (75 hp)?
The Mercury 75 HP uses the oil filter sold as 18-7914, plus its OEM and aftermarket cross-references (6 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 75 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 75 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 75 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 75 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 25 HP oil filter
- Mercury 90 HP oil filter
- Mercury 15 HP oil filter
- All Mercury maintenance guides
- Free Mercury boat valuation
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.