Yanmar 15W-40 Marine Engine Oil - 1 Gallon OEM Lubricant
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Yanmar 15W-40 Marine Diesel Engine Oil - 1 Gallon
This genuine Yanmar 15W-40 marine diesel engine oil is specifically formulated for Yanmar marine engines, providing superior protection, performance, and longevity. Essential for maintaining optimal engine operation and protecting your investment.
Key Features:
- Genuine Yanmar OEM 15W-40 marine diesel engine oil
- Specifically formulated for Yanmar marine engines
- Superior protection against wear, deposits, and corrosion
- Excellent performance in marine operating conditions
- Maintains proper viscosity across wide temperature range
- Protects against soot, acids, and combustion byproducts
- Extends engine life and maintains performance
- 1 gallon (3.78L) container for convenient oil changes
Marine-Specific Formulation:
Yanmar marine engine oil is specially formulated to meet the unique demands of marine diesel engines, which operate under different conditions than automotive or industrial engines. Marine engines typically run at constant RPM for extended periods, experience higher loads, and must resist moisture and salt contamination. This oil provides the specific additive package and performance characteristics required for marine applications.
15W-40 Viscosity Grade:
The 15W-40 multi-grade viscosity provides excellent cold-start protection (15W winter rating) while maintaining proper oil film thickness at operating temperatures (40 weight). This viscosity grade is ideal for most marine diesel engines operating in moderate to warm climates and provides reliable protection across a wide temperature range.
Engine Protection:
This premium oil provides superior protection against wear on critical engine components including bearings, cylinder walls, pistons, and valve train. Advanced additives resist oxidation, control deposits, neutralize acids from combustion, and protect against corrosion. The oil maintains its protective properties even under the sustained high-load operation typical of marine engines.
When to Change:
Follow Yanmar's recommended oil change intervals, typically every 100-250 operating hours or annually, whichever comes first. More frequent changes may be required for severe service conditions. Regular oil changes are the single most important maintenance task for engine longevity. Always use genuine Yanmar oil or equivalent marine diesel oil meeting Yanmar specifications.
Oil Change Procedure:
Change oil when engine is warm for complete drainage. Drain old oil completely and replace oil filter. Refill with proper quantity of fresh Yanmar 15W-40 oil according to engine specifications. Check oil level after running engine and top off as needed. Dispose of used oil properly at recycling facility.
Maintenance Best Practices:
Use only Yanmar genuine oil or equivalent marine diesel oil meeting Yanmar specifications. Change oil and filter on schedule - don't extend intervals. Check oil level regularly and maintain proper level. Monitor oil condition - change early if oil appears contaminated or degraded. Keep detailed maintenance records.
Technical Specifications:
- Type: Marine diesel engine oil
- Viscosity Grade: SAE 15W-40
- Container Size: 1 Gallon (3.78 Liters)
- Compatible with: Yanmar marine diesel engines
- Part Number: 41540G
Shipping information
In-stock and OEM parts: ship same or next business day.
Locally warehoused items: ship within 3–4 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.