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Block Cover Gasket – Fits Mercury Marine / Mercruiser 50-60 HP 3-Cylinder Outboard Engines (Replaces 27-437792)

Sale price $12.00 Regular price $19.00
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Worry-free returns

You may return most new, unopened items within 7 days of delivery for a full refund. We'll also pay the return shipping costs if the return is a result of our error (you received an incorrect or defective item, etc.).

You should expect to receive your refund within four weeks of giving your package to the return shipper, however, in many cases you will receive a refund more quickly. This time period includes the transit time for us to receive your return from the shipper (5 to 10 business days), the time it takes us to process your return once we receive it (3 to 5 business days), and the time it takes your bank to process our refund request (5 to 10 business days).

If you need to return an item, simply login to your account, view the order using the "Complete Orders" link under the My Account menu and click the Return Item(s) button. We'll notify you via e-mail of your refund once we've received and processed the returned item.

Delivery and Shipping

Free standard shipping on all orders under 1 KG

If you have any questions, feel free to email us at info@sierramarines.com, and we’ll get back to you within 20–36 hours.

Product Details

This replacement Block Cover Gasket is designed to fit Mercury Marine and Mercruiser 50 HP and 60 HP 3-cylinder, 2-stroke outboard engines, primarily from the 1990s through the 2000s. It ensures a proper seal for the engine block cover, preventing coolant leaks and maintaining engine integrity.

This part is a direct interchange for Mercury Marine part number 27-437792 and Quicksilver 27-437792.

  • Engineered as a direct replacement for a precise fit.
  • Meets or exceeds original equipment manufacturer (OEM) specifications.
  • Designed for use in marine gasoline engine environments.

Part Number Matrix

Use this matrix to confirm equivalent references across OEM and aftermarket.

Brand Part Number
Mercury Marine 27-437792
Quicksilver 27-437792

Engine & Model Compatibility

Confirm your engine model/year in the table below.

For Mercury Marine and Mercruiser engines, compatibility is often determined by serial number range rather than model year. Please verify your engine's serial number falls within the ranges listed.

Brand Model Rated HP Stroke Years OEM Part No. Notes
Mercury Marine 50 (3 CYL.) 50 2-Stroke 0A721308 & Up 27-437792
Mercury Marine 50 (3 CYL.) 50 2-Stroke 0B122930 THRU 0D000749 27-437792
Mercury Marine 50 (3 CYL.) 50 2-Stroke 9469200 THRU 9683054 27-437792
Mercury Marine 60 (3 CYL.) 60 2-Stroke 0A721308 & Up 27-437792
Mercury Marine 60 (3 CYL.) 60 2-Stroke 0B122930 THRU 0D000749 27-437792
Mercury Marine 60 (3 CYL.) 60 2-Stroke 9469200 THRU 9683054 27-437792

Technical Specs

Product Type
Block Cover Gasket
Installation
Direct replacement
Fuel Type
Gasoline
Dimensions
13" × 10" × 0.25" (330.2 mm × 254 mm × 6.35 mm)
Weight
0.4 lbs (0.18 kg)
Other Technical Attributes
Original Equipment Manufacturer (OEM) part

What’s in the Box

  • 1 x Gasket (27-437792)

Installation Notes

  1. Ensure the engine is off, cool, and disconnected from the power source.
  2. Drain coolant to a level below the block cover to prevent spills.
  3. Carefully unbolt and remove the old block cover and gasket.
  4. Thoroughly clean both the engine block and cover mating surfaces. Ensure all old gasket material, sealant, and debris are removed.
  5. Place the new gasket into position on the engine block, ensuring it aligns correctly.
  6. Reinstall the cover and tighten the bolts in the sequence and to the torque specified by the manufacturer.
  7. Refill the engine with coolant, then check for any leaks around the cover.

Troubleshooting & FAQ

How do I confirm this gasket fits my specific engine?

The most reliable method is to match your engine's model and serial number to the compatibility table. The serial number is critical for Mercury/Mercruiser engines, as it defines the correct parts for different production runs. Also, compare the images to your old part before ordering.

What are the signs of a failing block cover gasket?

Common symptoms include visible coolant leaks (often leaving a white or colored residue) on the side of the engine block, engine overheating, or white smoke from the exhaust, which can indicate coolant entering the combustion chamber.

When should this gasket be replaced?

Replace the block cover gasket whenever the cover is removed for service or inspection. It should also be replaced immediately if there are any signs of a leak or engine overheating.

Can I reuse my old gasket?

No. Gaskets are designed for single use. They compress and form a seal that is compromised upon removal. Always use a new gasket during reassembly to ensure a leak-proof seal.

OEM vs. Aftermarket?

This listing is an aftermarket replacement (not OEM). Built to OEM-level specifications with comparable materials. Manufactured in an ISO 9002 facility, batch-inspected for consistency.

Shipping speed & cost

We ship worldwide quickly—typical transit 5–15 days. Standard shipping is free; expedited options appear at checkout where available.

Warranty & returns

Covered by a 1-year warranty against manufacturing defects under normal use. If issues arise, contact support with your order details. Returns are accepted within our standard window (unused & in original condition). See our policy page or reach out for instructions.

Safety & Important Info

  • Verify images/specifications vs your original part. If anything differs—even if your model appears compatible—do not purchase.
  • This is an aftermarket replacement, not an OEM component.
  • Professional installation is recommended for safety and performance.

About Sea Sierra

  • Pro-Grade Standards — We supply marine parts engineered to OEM-level tolerances and tested for real-world conditions.
  • Fast Global Fulfillment — Free standard delivery to most regions in 5–15 days.
  • Manufacturer-Direct Value — Fair pricing without compromising on materials or QC.

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