Exhaust Outer Cover Gasket – Fits Yamaha 55HP Outboards (Replaces 663-41114-00-00)

$1.95 $3.00

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Product Details

This is a direct-fit Exhaust Outer Cover Gasket designed for Yamaha 55HP 2-stroke outboard motors manufactured between 1990 and 1993. It ensures a proper seal between the exhaust outer cover and the engine housing, preventing exhaust leaks and maintaining engine performance.

This part is a direct replacement for Yamaha OEM part number 663-41114-A0-00, which supersedes 663-41114-00-00.

Direct replacement installation requires no modifications.
Mounts between the exhaust outer cover and the engine housing.
Engineered for use in marine environments with gasoline engines.

Part Number Matrix

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

Brand	Part Number	Superseded By
Yamaha	663-41114-00-00	663-41114-A0-00

Engine & Model Compatibility

Confirm your engine model/year in the table below.

Brand	Model	Rated HP	Stroke	Years	OEM Part No.	Notes
Yamaha	55B (697)	55	2-Stroke	1990	663-41114-00-00	Superseded by 663-41114-A0-00
Yamaha	55B (697)	55	2-Stroke	1991	663-41114-00-00	Superseded by 663-41114-A0-00
Yamaha	CV55ED (6970)	55	2-Stroke	1990	663-41114-00-00	Superseded by 663-41114-A0-00
Yamaha	55BE (697)	55	2-Stroke	1993	663-41114-00-00	Superseded by 663-41114-A0-00

Technical Specs

Product Type: Exhaust Outer Cover Gasket
Installation: Direct replacement
Fuel Type: Gasoline
Connection: Mounts between exhaust outer cover and engine housing
Dimensions: 6.0" x 11.25" x 1.06"
Fitting Type: Gasket
Warranty: 90-Day Warranty (Seaboard Marine aftermarket)

What’s in the Box

1 x Gasket, Exhaust Outer Cover (663-41114-00-00/663-41114-A0-00)

Installation Notes

Ensure the engine is off and cool to the touch. Disconnect the battery.
Remove the engine cowling to access the exhaust components.
Carefully unbolt and remove the exhaust outer cover.
Remove the old gasket and thoroughly clean both mating surfaces. Ensure they are free of old gasket material, corrosion, and debris.
Position the new gasket correctly on the engine housing.
Reinstall the exhaust outer cover, ensuring it is properly aligned.
Tighten the bolts to the manufacturer's specified torque in a star or crisscross pattern to ensure even pressure.
Reconnect the battery and start the engine to check for any exhaust leaks around the cover.

Troubleshooting & FAQ

How do I know if my old gasket has failed?

Signs of a failed exhaust cover gasket include a noticeable exhaust leak (hissing or popping sound) from the side of the engine, visible soot or carbon tracks around the cover's edge, and a potential loss of engine power or rough idling.

Can I reuse my old gasket?

No. Gaskets are single-use components designed to crush and create a seal. Once compressed and heat-cycled, they will not seal properly if reused.

Is any sealant required with this gasket?

Generally, this type of gasket is designed to be installed dry. However, always consult your engine's service manual. Applying a thin layer of a high-temperature, non-hardening sealant may be recommended in some cases, but over-application can cause issues.

What is the difference between this and the OEM part?

This is a direct aftermarket replacement. While it is not an OEM part from Yamaha, it is manufactured to meet or exceed original equipment specifications for material, fit, and function, providing a reliable seal at a better value.

Does this fit all Yamaha 55HP models?

This part is confirmed to fit specific Yamaha 55HP 2-stroke models from 1990–1993. Always verify your engine's model and year against our compatibility table before ordering.

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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