Adapter Outer Powerhead Gasket – Fits Johnson/Evinrude V6 Looper (Replaces OMC 333879)

$17.19 $27.00

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Delivery and Shipping

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Product Details

This replacement Adapter Outer Powerhead Gasket is engineered for Johnson/Evinrude V6 Looper engines from 185 to 250 HP (3.0-3.3L), manufactured in 1985 and later. It ensures a precise seal between the powerhead and the adapter plate, preventing exhaust and coolant leaks.

It serves as a direct replacement for several part numbers, including Sierra 18-0965, Marine Pro 121-13-879, and OMC 333879 / 0333879 / 331214.

Designed for direct, hassle-free installation.
Made from durable paper/composite material to withstand marine environments.
Critical for maintaining engine compression and cooling efficiency.

Part Number Matrix

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

Brand	Part Number
Sierra	18-0965
Marine Pro	121-13-879
OMC	333879 / 0333879
OMC	331214

Engine & Model Compatibility

Confirm your engine model/year in the table below.

This gasket is specifically for Johnson/Evinrude V6 Looper outboards. Verify your model details for a perfect fit.

Brand	Model	Rated HP	Stroke	Years	OEM Part No.	Notes
Johnson/Evinrude	V6 Looper	185-250	2-Stroke	1985 and later	333879/0333879	Also referenced as 331214

Technical Specs

Product Type: Adapter Outer Powerhead Gasket
Installation: Direct replacement
Material: Paper/Composite
Dimensions: 17.13 × 14.0 × 0.13 inches
Weight: 5.3 ounces (0.15 kg)
Application: Powerhead to adapter gasket for V6 looper engines

What’s in the Box

1 x Adapter Outer Powerhead Gasket (Replaces OMC 333879)

Installation Notes

Disconnect the battery and ensure the engine is completely cool.
Carefully remove any components obstructing access to the powerhead adapter.
Unbolt and remove the old gasket, taking care not to damage the mating surfaces.
Thoroughly clean both the powerhead and adapter surfaces, removing all old gasket material and residue. A clean, smooth surface is critical for a proper seal.
Position the new gasket correctly, ensuring all bolt holes align perfectly.
Reassemble all components in reverse order, torquing bolts to the manufacturer's specified sequence and values.
After reassembly, check for any leaks before resuming normal operation.

Troubleshooting & FAQ

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

This gasket fits Johnson/Evinrude V6 Looper models (185-250 HP) from 1985 and later. The most reliable way to confirm fitment is to cross-reference your engine's original OEM part number with those listed in our Part Number Matrix (OMC 333879, 0333879, 331214).

What are the signs of a failed powerhead adapter gasket?

Common symptoms include visible water or oil leaks around the adapter plate, engine overheating, a noticeable loss of power or compression, or water contamination in the engine oil. If you notice any of these signs, inspect the gasket for damage or degradation.

Should I use sealant or adhesive with this gasket?

This gasket is typically designed to be installed dry. Applying sealants can sometimes interfere with its ability to create a proper seal. However, always consult your engine’s official service manual for model-specific recommendations.

What's the difference between OMC parts 333879 and 331214?

Both part numbers refer to the same component. OMC 331214 is often listed as a superseded or alternative number for 333879. They are functionally identical, and this aftermarket part replaces both.

OEM vs. Aftermarket?

This listing is an aftermarket replacement (not OEM). It is built to OEM-level specifications with comparable materials and manufactured in an ISO 9002 facility, where it is batch-inspected for consistency and quality.

Shipping speed & cost?

We ship worldwide quickly—typical transit is 5–15 days. Standard shipping is free; expedited options will appear at checkout where available for your location.

Warranty & returns?

This part is covered by a 1-year warranty against manufacturing defects under normal use. If any issues arise, please contact our support team with your order details. Returns are accepted within our standard window, provided the item is unused and in its original condition. See our policy page or reach out for instructions.

Safety & Important Info

Verify images and specifications against your original part before purchase. If anything differs—even if your model appears compatible—do not purchase.
This is an aftermarket replacement component, not an original equipment manufacturer (OEM) part.
Professional installation is highly recommended for safety and to ensure optimal engine performance.

About Sea Sierra

Pro-Grade Standards — We supply marine parts engineered to OEM-level tolerances and rigorously tested for real-world conditions.
Fast Global Fulfillment — Enjoy free standard delivery to most regions, with parts typically arriving in 5–15 days.
Manufacturer-Direct Value — By working directly with manufacturers, we offer fair pricing without compromising on materials or quality control.

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