Gasket – Fits Mercury/Mariner 15-25 HP (Replaces 27-414991)

$14.14 $22.00

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Product Details

This aftermarket Gasket – Fits Mercury/Mariner 15-25 HP is an essential component for various outboard motor applications. It is designed for Mercury/Mariner 15-25 HP 2-Stroke engines (1980 and later), including compatible Marathon, Sea Pro, and Super 15 models.

This part serves as a direct cross-reference for multiple OEM and aftermarket part numbers, including Mercury 27-414991, 41499/414991, Sierra 18-2716, and Quicksilver 92332.

Installation Type: Direct replacement
Application: Seals the exhaust outer cover
Material: Paper/Composite blend

Part Number Matrix

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

Brand	Part Number	Notes
Mercury	27-414991	Current OEM Reference
Mercury	41499	Superseded by 27-414991
Sierra	18-2716	Aftermarket Interchange
Quicksilver	92332	Aftermarket Interchange

Engine & Model Compatibility

Confirm your engine model/year in the table below.

For Mercury/Mariner models, engine compatibility is often determined by serial number range rather than production year. Ensure your engine's serial number falls within the specified range.

Brand	Model	Rated HP	Stroke	Years	OEM Part No.
Mercury	15 Marathon XD	15	2-Stroke	0P017000–0P325499	27-414991
Mercury	15 Sea Pro (XD)	15	2-Stroke	0P017000–0P325499	27-414991
Mercury	18XD	18	2-Stroke	6443973–0B238463	27-414991
Mercury	18XD	18	2-Stroke	7209533–0A730006	27-414991
Mercury	18XD	18	2-Stroke	9378151–9507380	27-414991
Mercury	20 (2 cyl.)	20	2-Stroke	0P325500 & Up	27-414991
Mercury	20 (2 cyl.)	20	2-Stroke	0G760300–0T979999	27-414991
Mercury	20 (2 cyl.)	20	2-Stroke	0P017000–0P325499	27-414991
Mercury	20 Jet	20	2-Stroke	0T980000–0T999999	27-414991
Mercury	20 Jet	20	2-Stroke	1B000001 & Up	27-414991
Mercury	20 Jet	20	2-Stroke	0G760300–0T979999	27-414991
Mercury	20 Jet	20	2-Stroke	0P017000–0P325499	27-414991
Mercury	20XD (2 cyl.)	20	2-Stroke	6443973–0B238463	27-414991
Mercury	20XD (2 cyl.)	20	2-Stroke	7209533–0A730006	27-414991
Mercury	20XD (2 cyl.)	20	2-Stroke	9415101–9507380	27-414991
Mercury	25 (2 cyl.)	25	2-Stroke	0P325500 & Up	27-414991
Mercury	25 (2 cyl.)	25	2-Stroke	0T980000–0T999999	27-414991
Mercury	25 (2 cyl.)	25	2-Stroke	1B000001 & Up	27-414991
Mercury	25 Marathon, Super 15 (2 cyl.)	25	2-Stroke	0G760300–0T979999	27-414991
Mercury	25 Marathon, Super 15 (2 cyl.)	25	2-Stroke	0P017000–0P325499	27-414991
Mercury	25 Sea Pro, Super 15 (2 cyl.)	25	2-Stroke	0G760300–0T979999	27-414991
Mercury	25 Sea Pro, Super 15 (2 cyl.)	25	2-Stroke	0P017000–0P325499	27-414991
Mercury	25XD	25	2-Stroke	6443973–0B238463	27-414991
Mercury	25XD	25	2-Stroke	7209533–0A730006	27-414991
Mercury	25XD	25	2-Stroke	9415101–9507380	27-414991
Mercury	MERC 25XS	25	2-Stroke	85A001 and up	27-414991

Technical Specs

Product Type: Gasket
Application: Exhaust Outer Cover
Material: Paper/Composite
Installation: Direct Replacement
Dimensions: 19.0 x 15.0 x 0.2 cm (approx. 7.5 x 5.9 x 0.08 inches)
Weight: 0.05 lb (0.023 kg)

What’s in the Box

1x Gasket (Replaces OEM 27-414991)

Installation Notes

Disconnect the battery and ensure the engine is cool.
Access the exhaust outer cover. Location may vary by engine model.
Carefully remove the bolts or fasteners securing the cover.
Remove the old gasket. Take care not to damage the mating surfaces.
Thoroughly clean both the cover and the engine block surfaces. All old gasket material and residue must be removed for a proper seal.
Position the new gasket correctly. Do not use sealant unless specified by the engine manufacturer.
Reinstall the cover and tighten fasteners to the manufacturer's recommended torque specifications in the correct sequence.
Reconnect the battery and check for exhaust leaks after starting the engine.

Troubleshooting & FAQ

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

This gasket fits specific Mercury/Mariner 15-25 HP 2-Stroke models. The most reliable method is to check your engine's serial number against the ranges listed in our Engine & Model Compatibility table.

What does this gasket seal?

This is an exhaust outer cover gasket. It creates a seal between the exhaust cover and the engine block, preventing exhaust gas and water leaks.

Do I need to use sealant with this gasket?

Generally, no. This gasket is designed to be installed dry. Only apply sealant if it is explicitly recommended in your engine's service manual for this specific application. Using sealant unnecessarily can cause improper seating and leaks.

What are the signs of a failing exhaust cover gasket?

Common symptoms include a noticeable exhaust leak (louder engine noise), visible soot or black streaks around the exhaust cover, water leaks in that area, and potential loss of engine performance.

The dimensions seem slightly different from my original. Why?

The provided dimensions are based on the latest manufacturing data for this aftermarket part. Minor differences from an aged or compressed original gasket are normal. The critical factor is confirming your engine model and part number in the compatibility lists.

My engine isn't listed, but the old part looks the same. Can I use it?

We strongly advise against it. Even if a gasket appears visually similar, small differences in material, thickness, or bolt hole alignment can lead to leaks and engine damage. Only use this part if your model is explicitly listed.

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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Manufacturer-Direct Value — Fair pricing without compromising on materials or QC.

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