Gasket Set – Fits Mercury 75–115 HP 4-Stroke Outboard Motors (27-897534A07)

$328.55

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Delivery and Shipping

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Product Details

This is a complete Gasket Set for Mercury 75-115 HP 4-Stroke Outboard Motors (p/n 27-897534A07), designed for servicing the powerhead on a range of EFI engines. It fits Mercury 75 HP, 80 HP, 90 HP, 100 HP, and 115 HP models with serial numbers from 1B366823 through 2B094995. Engineered to meet OEM specifications, it ensures a direct fit and reliable, long-lasting seal.

This kit serves as a direct replacement for Mercury OEM powerhead gasket set 27-897534A07.

Engineered for direct OEM-replacement installation.
Designed for use in gasoline marine engines.
Provides essential gaskets for a standard powerhead service.

Part Number Matrix

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

Brand	Part Number	Notes
Mercury	27-897534A07	OEM Powerhead Gasket Set

Engine & Model Compatibility

Confirm your engine model/year in the table below.

For Mercury Marine engines, ensure your model and serial number fall within the specified ranges to guarantee compatibility.

Brand	Model	Rated HP	Stroke	OEM Part No.	Notes
Mercury	75 EFI	75	4-Stroke	27-897534A07	Serial Range: 1B366823 THRU 2B094995
Mercury	80 EFI	80	4-Stroke	27-897534A07	Serial Range: 0P459572 THRU 2B094995, 1B366823 THRU 2B094995
Mercury	90 EFI	90	4-Stroke	27-897534A07	Serial Range: 1B366823 THRU 2B094995
Mercury	100 EFI	100	4-Stroke	27-897534A07	Serial Range: 0P459572 THRU 2B094995, 1B366823 THRU 2B094995
Mercury	115 EFI	115	4-Stroke	27-897534A07	Serial Range: 1B366823 THRU 2B094995

Technical Specs

Product Type: Powerhead Gasket Set
Installation: OEM Replacement
Fuel Type: Gasoline
Dimensions: 64.0 cm L x 37.0 cm W x 3.0 cm H
Weight: 1.80 lbs (0.82 kg)
GTIN: 745061724891

What’s in the Box

1 x Gasket Set, Powerhead (27-897534A07)

Installation Notes

Professional installation is highly recommended. Always refer to your engine's official service manual for detailed procedures, torque specifications, and safety warnings. Ensure all mating surfaces are clean, dry, and free of old gasket material or debris before installing the new gaskets to prevent leaks.

Troubleshooting & FAQ

What specific engines does this gasket set fit?

This set is designed for Mercury 75, 80, 90, 100, and 115 HP 4-Stroke EFI outboard models. It is critical to verify that your engine's serial number falls within the ranges specified in the compatibility table to ensure a proper fit.

How can I tell if my powerhead gaskets are failing?

Common signs of a failed powerhead gasket include engine overheating, loss of power, water in the cylinders or oil (which appears milky), and visible water or exhaust leaks from the powerhead seams. A compression test can also help diagnose a blown gasket.

Is this a complete kit for a powerhead rebuild?

This is a comprehensive powerhead gasket set that includes the essential gaskets for reassembly. However, depending on the nature of your repair, you may need additional seals, O-rings, or specific hardware not included. Always cross-reference with your service manual's required parts list.

When should powerhead gaskets be replaced?

Powerhead gaskets do not have a fixed replacement interval. They are typically replaced only when the powerhead is disassembled for service, repair, or during a complete engine rebuild. They are designed to last the life of the engine under normal operating conditions.

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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