Transfer Port Cover Gasket – Fits Mercury Marine Outboards (Replaces 27-279361)

$3.50

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Product Details

This Transfer Port Cover Gasket – Fits Mercury Marine Outboards (Replaces 27-279361) is engineered for specific Mercury Marine outboard engines, providing a reliable seal for the transfer port cover. It is designed primarily for 30-50 HP, 4-cylinder outboard models manufactured from the 1990s onward.

This part offers a direct interchange for Mercury Marine 27-279361 and 27-27936, Sierra 18-0870, GLM 3060, and Mallory 9-60063.

Installs as a direct replacement for the original OEM gasket.
Creates a durable seal for the transfer port cover, preventing compression and fuel/air leaks.
Engineered to fit compatible Mercury Marine 30-50 HP 4-cylinder outboards.

Part Number Matrix

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

Brand	Part Number
Mercury Marine	27-279361
Mercury Marine	27-27936
Sierra	18-0870
GLM	3060
Mallory	9-60063

Engine & Model Compatibility

Confirm your engine model/year in the table below.

Compatibility information for Mercury Marine engines is listed below.

Brand	Model	Rated HP	Years	OEM Part No.	Notes
Mercury	40 (4 CYL.)	40	0C159200 and Up	27-279361
Mercury	40 (4 CYL.)	40	9570790 and Up	27-279361
Mercury	40 JET 30 JET	40/30	0C159200 thru 0G589999	27-279361
Mercury	30 JET	30	9570790 and Up	27-279361
Mercury	45 (4 CYL.)	45	0A719281 & Up	27-279361
Mercury	45 (4 CYL.)	45	0B110789 & Up	27-279361
Mercury	45 (4 CYL.)	45	9466692 & Up	27-279361
Mercury	Race Outboard 44 XS	44		27-279361	Qty required: 2
Mercury	45/50 HP	45/50		27-279361	Qty required: 2

Technical Specs

Product Type: Transfer Port Cover Gasket
Installation: Direct replacement
Dimensions: 7.5 × 6.0 × 1.03 in
Weight: 0.0045 kg (0.16 ounces)
Application: Seals transfer port cover
OEM Cross Reference: Mercury Marine 27-279361, 27-27936
Quantity per Package: 1
Compatible with: Mercury Marine 30-50 HP 4-cylinder outboards

What’s in the Box

1 x Transfer Port Cover Gasket (27-279361)

Installation Notes

Ensure the engine is off, cool, and disconnected from the battery.
Locate and carefully remove the fasteners for the transfer port cover.
Remove the old gasket. Thoroughly clean any remaining gasket material or residue from both the engine block and the cover surfaces.
Position the new gasket, ensuring it aligns correctly with the bolt holes and sealing surfaces.
Reinstall the transfer port cover and tighten the fasteners in a staggered sequence to the manufacturer's recommended torque specifications.
Reconnect the battery, start the engine, and inspect for any air or fuel leaks around the cover.

Troubleshooting & FAQ

How do I know if the transfer port cover gasket is failing?

Symptoms of a faulty gasket include visible fuel or oil residue around the transfer port cover, difficulty achieving a stable idle, reduced engine performance, or a noticeable loss of crankcase compression.

Will this fit my specific 4-cylinder Mercury outboard?

This gasket is designed for many 30-50 HP 4-cylinder models from the 1990s and later. To ensure a correct fit, please cross-reference your engine's serial number with the compatibility chart or match your old part number to the equivalents listed in the Part Number Matrix.

What is the function of a transfer port gasket?

It creates an essential airtight seal for the transfer port cover. In two-stroke engines, this seal maintains crankcase compression, which is critical for the proper transfer of the fuel/air mixture from the crankcase to the combustion chamber.

Should I use sealant with this gasket?

In most cases, this gasket is designed for a dry installation. Applying sealant is generally not necessary unless specifically instructed by your engine's service manual. Always refer to the official manual for manufacturer-approved procedures.

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

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