Lower Unit Oil Seal – Fits OMC Cobra, Johnson, Evinrude (Replaces 332261, 0332261, 18-2065, 86520)

Product Details

This Lower Unit Oil Seal is a direct-fit replacement for OMC Cobra, Johnson, and Evinrude marine lower gearcase units. Engineered to prevent oil leakage and contamination in demanding marine environments, this seal maintains proper lubrication and extends lower unit life.

This seal directly replaces OEM part numbers 332261, 0332261, and aftermarket equivalents 18-2065 and 86520.

• Precision-molded seal designed for OMC Cobra lower gearcase applications
• Ensures proper oil retention in the lower unit assembly
• Compatible with fresh and saltwater environments

Part Number Matrix

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

Engine & Model Compatibility

Confirm your engine model/year in the table below.

Technical Specs

Part Type

Lower Unit Oil Seal

Application

OMC Cobra, Johnson, Evinrude Lower Gearcase

OEM Reference

332261, 0332261

Aftermarket Cross-Reference

18-2065, 86520

Material

Oil-resistant elastomer

Environment

Marine (fresh & saltwater)

What's in the Box

• Oil seal × 1

Installation Notes

1. Remove the lower unit from the drive assembly according to your service manual.
2. Drain all lower unit oil and inspect for metal debris or contamination.
3. Remove the old oil seal carefully using a seal puller or appropriate tool to avoid damaging the seal bore.
4. Clean the seal bore thoroughly and inspect for scratches, corrosion, or damage.
5. Lightly coat the new seal outer diameter and lip with lower unit oil.
6. Press the new seal into place evenly using a seal driver or appropriate installation tool until fully seated.
7. Reassemble the lower unit components and refill with the manufacturer-specified lower unit oil.
8. Check for leaks after initial operation and monitor oil level regularly.

Troubleshooting & FAQ

How do I know if my lower unit oil seal is failing?

Common signs include visible oil leaking from the lower unit, milky or discolored lower unit oil (indicating water intrusion), or lower oil levels between service intervals. If you notice any of these symptoms, inspect and replace the seal promptly to prevent gearcase damage.

Can I reuse the old seal during lower unit service?

No. Oil seals are designed for single-use installation and lose their sealing ability once removed. Always replace the seal whenever the lower unit is disassembled to ensure proper oil retention and prevent water contamination.

What happens if I don't replace a leaking lower unit oil seal?

A leaking seal can allow water to enter the gearcase, contaminating the oil and leading to corrosion, bearing failure, and eventual gearcase seizure. Oil loss also reduces lubrication, causing excessive wear on gears and bearings. Replace failing seals immediately to avoid costly repairs.

Do I need special tools to install this seal?

A seal driver or appropriately sized socket that matches the seal outer diameter is recommended for even, damage-free installation. Avoid using hammers or punches directly on the seal, as uneven pressure can distort the seal or damage the bore.

How often should I replace lower unit oil seals?

Replace oil seals whenever the lower unit is disassembled for service, or immediately if you detect leaks or oil contamination. Regular inspection during routine maintenance (every 100 hours or annually) helps catch seal degradation early.

Will this seal work in saltwater applications?

Yes. This seal is designed for marine use in both fresh and saltwater environments. Ensure you use the correct lower unit oil specified by the manufacturer and rinse the lower unit after saltwater use to maximize seal life.

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 against 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.