Mercury Synthetic Blend 4-Stroke Marine Engine Oil, 10W-30, 1 Qt – 8M0149203
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Mercury Synthetic Blend 4-Stroke Marine Engine Oil – 10W-30, 1 Quart
Keep your Mercury 4-stroke outboard protected with this genuine Mercury Marine synthetic blend engine oil. Formulated specifically for marine 4-stroke applications, it delivers corrosion protection, shear strength, and viscosity retention designed for the high-rpm, high-load demands of outboard operation — including humid, salty, and seasonal storage conditions where standard automotive oils fall short.
Compatible Applications
- Mercury 4-stroke outboards up to 150 HP where 10W-30 is specified
- Mercury 3.4L V6 4-stroke outboards where 10W-30 is called for
- Mercury 4.6L V8 4-stroke outboards where 10W-30 is called for
- Always confirm the required oil grade in your engine’s owner’s manual or service manual using your exact model and serial number
Part Details
- OEM Part Number: 8M0149203
- Brand: Mercury Marine
- Type: Synthetic blend 4-stroke marine engine oil
- Viscosity: 10W-30
- Volume: 1 Quart (946 mL)
- Base: Synthetic blend
- Application: Mercury 4-stroke outboard engines
- Condition: New OEM
Service Interval
Use during routine oil changes on applicable Mercury 4-stroke outboard engines. Mercury recommends oil changes at 100 hours or annually, whichever comes first. Always replace the oil filter at the same time. Refer to your engine’s service manual for the exact interval and capacity for your model.
Technical FAQ
- Can I use automotive 10W-30 instead? No. Marine engine oils contain corrosion inhibitors and additives not found in automotive oils. Mercury specifically recommends marine-grade oil to protect against the unique demands of marine operation, including moisture exposure and extended storage periods.
- How much oil does my engine take? Capacity varies by engine model. Check your owner’s manual or service manual for the exact oil capacity and fill procedure for your specific engine.
- Is this the same as 8M0149213? No — 8M0149213 is the 1-gallon (3.78L) size of the same 10W-30 synthetic blend formula. See the 1-gallon listing for bulk purchases.
- What oil filter do I need? Filter fitment varies by engine. See our Mercury oil filter listings and confirm by model and serial number.
Related Parts
- Mercury Synthetic Blend 10W-30, 1 Gallon – 8M0149213
- Mercury Quicksilver Oil Filter – 877761K01
- Mercury Quicksilver Oil Filter – 877769K01
- Mercury Quicksilver Oil Change Kit – 8M0081917
- Mercury Quicksilver Oil Change Kit – 8M0081914
- Mercury Quicksilver 100-Hour Service Kit – 8M0094232
- Mercury 4-Stroke Oil Drain Screw Washer – 12-803516
Parts Desk Insights
The most common mistake with outboard oil changes is using automotive oil instead of a marine-specific formula. Marine engines run at sustained high RPM, often in humid or salty environments, and sit idle for months during off-season storage — conditions that demand the corrosion inhibitors and shear-stable additives found in marine-grade oil. The 10W-30 grade is Mercury’s spec for most of their mid-range 4-stroke outboards, but always verify against your specific engine model and serial number before purchasing — some engines in the same horsepower range call for a different viscosity. If you’re doing a full service, pair this oil with the correct oil filter and a new drain screw washer to complete the job properly.
Shipping information
In-stock and OEM parts: ship same or next business day.
Locally warehoused items: ship within 1-3 business days.
Special-order items: timeline confirmed after order.
Returns & warranty
Returns & Satisfaction Guarantee
We stand firmly behind the quality of every product we sell. Your confidence matters to us — and we back it with a straightforward 30-Day Satisfaction Guarantee.
If you are not fully satisfied, you may request a return within 30 days of delivery. All returns must receive pre-approval prior to being sent back. Unauthorized returns will not be accepted.
To qualify for a return:
Item must be in new, unused condition
Product must be in its original packaging
All parts, components, hardware, manuals, and accessories must be included
Packaging must be undamaged and suitable for resale
Important:
Electronics are strictly inspected. No returns on open-box electronics. Exceptions may apply only with prior written approval. Any electronic unit that has been installed, powered, activated, or altered may not be eligible for return.
We are serious about product integrity — and equally serious about taking care of our customers. If there is ever a product issue, contact us immediately so we can make it right.
For return authorization, please contact our support team before shipping anything back.