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Celebrating 50 years of Trusted Marine Service
50 years of Trusted Marine Service

Yanmar Y-Spec Synthetic Engine Oil 50540 - 1 Quart Marine Diesel

Original price $12.79 - Original price $12.79
Original price $12.79
$12.79
$12.79 - $12.79
Current price $12.79
Availability:
35 in stock, ready to be shipped

Free returns on all eligible orders

You have 30 days to request a return. All sale items are final sale.

Genuine Yanmar Y-Spec Synthetic Engine Oil - Professional Marine Lubricant

OEM synthetic engine oil formulated specifically for Yanmar marine diesel engines. Premium full-synthetic lubricant that provides superior protection, extended drain intervals, and optimal performance in demanding marine environments.

Key Features:

  • Genuine Yanmar OEM product (50540)
  • Full synthetic formulation for maximum protection
  • 1 quart (946ml) container
  • Engineered specifically for Yanmar marine diesel engines
  • Superior thermal stability and oxidation resistance
  • Excellent cold-start performance
  • Extended drain intervals reduce maintenance costs

Applications:

Designed for Yanmar marine diesel engines. Provides year-round protection in all operating conditions, from cold starts to high-temperature continuous operation.

Performance Benefits:

Advanced synthetic formula provides superior wear protection, reduces friction for improved fuel economy, and maintains viscosity under extreme temperatures. Protects against sludge, varnish, and deposits while extending engine life.

Maintenance Note:

Follow Yanmar's recommended oil change intervals. Use only Yanmar Y-Spec oil to maintain warranty coverage and ensure optimal engine protection. Check oil level regularly and top up as needed.

Quality Assurance:

Backed by Yanmar's engineering excellence and reputation for reliable marine propulsion systems. Professional-grade synthetic oil for commercial and recreational vessels.

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.

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