Base Gasket – Fits Johnson/Evinrude 50-70 HP 3-Cylinder Engines (Replaces 329828)

$4.39 $7.00

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Product Details

This is a direct replacement Base Gasket – Fits Johnson/Evinrude 50-70 HP 3-Cylinder Engines. It is designed for models from 1986 and later that feature a 3.187-inch bore size, ensuring a precise and reliable seal between the powerhead and the adapter plate.

This part serves as a direct cross-reference for Johnson/Evinrude part numbers 329828 and 777416, as well as aftermarket equivalents WSM 510-06, GLM Marine 35430, and EMP 27-02205.

Installs between the powerhead and adapter plate.
Engineered specifically for 3-cylinder engines with a 3.187" bore.
Requires one gasket per engine for a complete repair.

Part Number Matrix

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

Brand	Part Number	Notes
Johnson/Evinrude	329828	Supersedes part number 777416
Johnson/Evinrude	777416	Superseded by 329828
WSM	510-06
GLM Marine	35430
EMP	27-02205

Engine & Model Compatibility

Confirm your engine model/year in the table below.

This gasket is designed for specific Johnson/Evinrude 3-cylinder outboard engines.

Brand	Model	Rated HP	Years	OEM Part No.	Notes
Johnson/Evinrude	Various 3-cylinder models	50–70 HP	1986–up	329828	Supersedes 777416

Technical Specs

Product Type: Base Gasket
Installation: Between powerhead and adapter plate
Bore Size: 3.187 inches (80.95 mm)
Cylinder Configuration: 3-cylinder
Required Quantity: 1 per engine
Dimensions: 18.0" L x 17.0" W x 1.5" H
Other Technical Attributes: Designed for engines with 3.187" bore

What’s in the Box

1 x Base Gasket (329828)

Installation Notes

Disconnect the battery and all fuel lines for safety before beginning work.
Carefully remove the powerhead from the adapter plate, keeping track of all fasteners and connections.
Remove the old base gasket completely. Thoroughly clean both mating surfaces to remove any old gasket material or debris.
Inspect the powerhead and adapter plate surfaces for flatness and any damage that could prevent a proper seal.
Position the new gasket, ensuring all bolt holes and passages align perfectly.
Reinstall the powerhead, tightening the fasteners in the sequence and to the torque values specified in your engine’s service manual.
Reconnect all electrical and fuel lines before attempting to start the engine.

Troubleshooting & FAQ

How do I know if this gasket fits my specific engine model?

This gasket fits Johnson/Evinrude 50, 60, and 70 HP 3-cylinder outboards from 1986 and later with a 3.187" bore. The best way to confirm is to match your original part number to 329828 or an equivalent listed in our Part Number Matrix.

What are the signs of a failing base gasket?

Common symptoms include water intrusion into the cylinders, a noticeable loss of compression, poor or rough engine performance, or visible water and exhaust leaks from the seam between the powerhead and adapter plate.

Is this gasket for 2-stroke or 4-stroke engines?

It is designed for the 3-cylinder Johnson/Evinrude outboards from the specified era, which are typically 2-stroke engines. However, you should always confirm compatibility by checking your engine's specific part number.

Can I reuse my old base gasket?

No. Gaskets create a seal by compressing and are designed for a single use. Always install a new gasket whenever the powerhead is removed to guarantee a proper, leak-free seal.

Do I need to use a sealant with this gasket?

Generally, this type of gasket is designed to be installed dry. However, we always recommend consulting your engine’s official service manual for specific instructions regarding the use of sealants.

What is the difference between part number 329828 and 777416?

Part number 329828 is the newer, updated OEM part that supersedes the older 777416. They are functionally identical in fit and performance, and this aftermarket gasket is a direct replacement for both.

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.

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