Exhaust Gasket – Fits Mercury/Mariner 40-50HP (1995-1997) (Replaces 27-826738)

$15.30 $24.00

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Exhaust Gasket – Fits Mercury/Mariner 40-50HP (1995-1997) (Replaces 27-826738) is backordered and will ship as soon as it is back in stock.

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Product Details

This Exhaust Gasket – Fits Mercury/Mariner 40-50HP (1995-1997) is a crucial component for maintaining a proper seal between the exhaust adaptor plate and the powerhead on Mercury and Mariner 40–50HP 2-stroke outboard engines manufactured between 1995 and 1997.

It serves as a direct replacement for OEM part number 27-826738 and aftermarket cross-reference AM826738.

Installs between the exhaust adaptor plate and the powerhead.
Secures with a simple bolt-on connection for a reliable fit.
Crafted from durable, non-metallic gasket material to ensure a lasting seal.

Part Number Matrix

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

Brand	Part Number	Notes
Mercury	27-826738	OEM
Mercury	AM826738	Aftermarket

Engine & Model Compatibility

Confirm your engine model/year in the table below.

For Mercury and Mariner owners, this gasket is designed for specific 40HP and 50HP two-stroke models from the mid-90s. Please verify your engine details against this list.

Brand	Model	Rated HP	Stroke	Years	OEM Part No.
Mercury	40HP	40	2-Stroke	1995–1997	27-826738
Mercury	50HP	50	2-Stroke	1995–1997	27-826738
Mariner	40HP	40	2-Stroke	1995–1997	27-826738
Mariner	50HP	50	2-Stroke	1995–1997	27-826738

Technical Specs

Product Type: Exhaust Gasket
Installation: Between exhaust adaptor plate and powerhead
Connection: Bolt-on
Housing Material: Gasket material (non-metallic)
Dimensions: 20.5 cm L x 17.0 cm W x 0.3 cm H
Other Technical Attributes: Designed as an aftermarket equivalent to OEM specifications

What’s in the Box

1 x Exhaust Gasket (Replaces 27-826738)

Installation Notes

Ensure the engine is off, cool, and disconnected from the power source before starting.
Carefully remove the powerhead and any other components obstructing access to the exhaust adaptor plate.
Remove the old gasket and thoroughly clean both mounting surfaces of any debris or residue. A clean, smooth surface is critical for a proper seal.
Position the new gasket correctly, aligning it with the bolt holes on the adaptor plate.
Reassemble all components in reverse order, ensuring bolts are tightened to the manufacturer's specified torque settings.
Once assembled, start the engine and carefully check for exhaust leaks around the newly sealed joint.

Troubleshooting & FAQ

How do I know if this gasket will fit my engine?

This gasket is specifically designed for Mercury and Mariner 40-50HP 2-stroke outboards from 1995–1997. The most reliable way to confirm fitment is by matching your old part number to 27-826738. You can also verify your engine’s model and year in the compatibility table provided on this page.

What are the signs of a failing exhaust gasket?

Common symptoms include a noticeably louder engine noise (indicating an exhaust leak), visible black soot streaks around the gasket joint, reduced engine performance, or water leaking into the engine cowling area. If you notice any of these signs, the gasket should be inspected for damage.

Is this the same as a powerhead base gasket?

While it is located at the base of the powerhead, its technical name is an "exhaust adaptor plate gasket." The term "powerhead base gasket" can refer to a different part. Always verify the shape and part number against your old component to ensure you are ordering the correct item.

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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