Air Silencer Cover Gasket – Fits Johnson/Evinrude V4 Engines (Replaces 321722)

$9.74 $15.00

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Product Details

This is an aftermarket Air Silencer Cover Gasket designed for compatibility with a range of Johnson/Evinrude V4 Crossflow outboard engines. It ensures a proper seal for the air silencer, which is critical for maintaining engine performance and reducing operational noise.

This part is a direct replacement for OEM part number 321722 and Sierra part number 18-0985.

Engineered for direct-fit installation.
Resistant to corrosion, heat, and pressure in marine environments.
Package includes one gasket for a complete replacement.

Part Number Matrix

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

Brand	Part Number
Johnson/Evinrude	321722
Sierra	18-0985

Engine & Model Compatibility

Confirm your engine model/year in the table below.

For Johnson/Evinrude owners, please verify that your V4 Crossflow engine uses the specified OEM part number.

Brand	Model	OEM Part No.
Johnson/Evinrude	V4 Crossflow	321722

Technical Specs

Product Type: Air Silencer Cover Gasket
Installation: Direct replacement
Fuel Type: Gasoline
Dimensions: 24.5" L x 21.0" W x 0.5" H
Warranty: 90-day warranty (from Max Marine Outlet)
Other Technical Attributes: Designed for marine environments with resistance to corrosion, heat, and pressure

What’s in the Box

1 x Air Silencer Cover Gasket (321722)

Installation Notes

Ensure the engine is off and cool to the touch. Disconnect the battery terminals for safety.
Locate and unbolt the air silencer cover from the engine block.
Carefully remove the old, worn-out gasket. Take note of its orientation.
Thoroughly clean both mating surfaces on the engine and the cover. Remove all old gasket material, sealant, or debris.
Position the new gasket correctly onto the engine block.
Reinstall the air silencer cover, ensuring it is properly aligned with the gasket.
Tighten the bolts in a crossing pattern to the manufacturer's recommended torque specifications to ensure an even seal.
Reconnect the battery and test the engine for air leaks at idle.

Troubleshooting & FAQ

Will this gasket fit my specific Johnson/Evinrude engine?

This gasket is designed for V4 Crossflow models that use OEM part number 321722. Always cross-reference the part number with your service manual or existing part to guarantee compatibility.

How do I know if my old air silencer gasket needs replacing?

Signs of a failing gasket include a high-pitched whistling or hissing sound from the engine, a noticeable decrease in engine performance, or visible cracking and brittleness on the old gasket upon inspection.

What is the difference between this aftermarket gasket and an OEM one?

Our aftermarket parts are manufactured to meet or exceed OEM specifications using comparable, high-quality materials. They provide the same performance and seal as the original at a better value.

Is any gasket sealant or adhesive required for installation?

Generally, this type of gasket is installed dry. However, always consult your engine's service manual. If the manual specifies a sealant, use one that is appropriate for marine fuel and oil applications.

How often should this gasket be replaced?

It should be inspected during routine service and replaced whenever the air silencer cover is removed or if there are any signs of a leak or material degradation.

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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