Lower Unit Seal Kit – Fits Johnson/Evinrude 35-75HP (Replaces 0396355, 0777562)
Lower Unit Seal Kit – Fits Johnson/Evinrude 35-75HP (Replaces 0396355, 0777562) is backordered and will ship as soon as it is back in stock.
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Delivery and Shipping
Delivery and Shipping
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Lower Unit Seal Kit – Fits Johnson/Evinrude 35-75HP (Replaces 03963...
Lower Unit Seal Kit – Fits Johnson/Evinrude 35-75HP (Replaces 0396355, 0777562) is backordered and will ship as soon as it is back in stock.
Product Details
This Lower Unit Seal Kit – Fits Johnson/Evinrude 35-75HP 1975–1988 provides all necessary seals and gaskets to service the gearcase on Johnson/Evinrude outboards. It is designed for 35-75HP, 2-cylinder and 3-cylinder models with the small gearcase manufactured between 1975 and 1988.
This kit serves as a direct replacement for Sierra 18-2659, GLM 87603, Mallory 9-74102, WSM 446-102, and Johnson/Evinrude OEM parts 0396355 and 0777562.
- Engineered with corrosion-resistant materials suitable for harsh marine environments.
- Includes drain/fill plug washers and all required O-rings for a complete overhaul.
- Professional installation is recommended to ensure a proper seal and long-term performance.
Part Number Matrix
Use this matrix to confirm equivalent references across OEM and aftermarket suppliers.
| Brand | Part Number | Notes |
|---|---|---|
| Johnson/Evinrude | 0396355 | OEM |
| Johnson/Evinrude | 0777562 | OEM Superseded |
| Sierra | 18-2659 | Aftermarket |
| GLM | 87603 | Aftermarket |
| Mallory | 9-74102 | Aftermarket |
| WSM | 446-102 | Aftermarket |
Engine & Model Compatibility
Confirm your engine model/year in the table below.
This kit is specifically for Johnson/Evinrude models with a small gearcase.
| Brand | Model | Rated HP | Stroke | Years | OEM Part No. | Notes |
|---|---|---|---|---|---|---|
| Johnson/Evinrude | 2 Cyl 3.187 Bore Looper | 35 | 2-Stroke | 1986–1987 | 0396355 | Small gearcase |
| Johnson/Evinrude | 2 Cyl 3.187 Bore Looper | 40 | 2-Stroke | 1985–1988 | 0396355 | Small gearcase |
| Johnson/Evinrude | 2 Cyl 3.187 Bore Looper | 48 | 2-Stroke | 1987–1988 | 0396355 | Small gearcase |
| Johnson/Evinrude | 2 Cyl 3.187 Bore Looper | 50 | 2-Stroke | 1985–1988 | 0396355 | Small gearcase |
| Johnson/Evinrude | 2 Cyl 3.187 Bore Looper | 60 | 2-Stroke | 1985 | 0396355 | Small gearcase |
| Johnson/Evinrude | 3 Cyl 3.000 Bore Looper | 60 | 2-Stroke | 1986–1987 | 0396355 | Small gearcase |
| Johnson/Evinrude | 3 Cyl 3.000 Bore Looper | 70 | 2-Stroke | 1985 | 0396355 | Small gearcase |
| Johnson/Evinrude | 3 Cyl 3.000 Bore Looper | 75 | 2-Stroke | 1985–1987 | 0396355 | Small gearcase |
| Johnson/Evinrude | Various models | 35-75 | 2-Stroke | 1975–1988 | 0396355 | Small gearcase |
Technical Specs
- Product Type
- Lower Unit/Gearcase Seal Kit
- Installation
- Professional installation recommended
- Weight
- 0.18 kg (0.4 lb)
- Thread Size
- Various (includes drain/fill plug washers)
- Operating Temperature
- Marine environment standard
- Warranty
- Varies by manufacturer
- Other Technical Attributes
- Corrosion-resistant materials for marine environments
What’s in the Box
- 1 x Impeller Housing Gasket (18-0969)
- 1 x Oil Seal (18-2059)
- 2 x Oil Seal (18-2060)
- 1 x Oil Seal (18-2064)
- 1 x Gearcase Cover Seal (18-2532)
- 1 x Exhaust Leg Seal (18-2537)
- 1 x Shift Housing Gasket (18-2855)
- 2 x Drain/Fill Plug Washer (18-4248)
- 1 x O-Ring (18-7115)
- 1 x O-Ring (18-7120)
- 1 x O-Ring (18-7137)
- 1 x O-Ring (18-7140)
- 2 x O-Ring (18-7145)
- 3 x O-Ring (18-7475)
Installation Notes
- Position the outboard securely on an engine stand or with the lower unit clear for access.
- Place a drain pan under the gearcase and remove the upper (vent) and lower (drain) screws to drain the gear oil.
- Disconnect the shift linkage and remove the bolts securing the lower unit to the engine's exhaust housing.
- Carefully lower and remove the gearcase assembly from the outboard.
- Disassemble the gearcase components, including the water pump and bearing carrier, to access the old seals. Keep parts organized.
- Use a seal puller or appropriate tool to carefully remove all old seals, gaskets, and O-rings.
- Thoroughly clean all sealing surfaces, ensuring they are free of old gasket material, corrosion, or debris.
- Install the new seals and O-rings from the kit, applying a light coat of marine grease to the lips of the seals.
- Reassemble the gearcase components in reverse order, ensuring correct alignment and torque specifications.
- Reinstall the lower unit, reconnect the shift linkage, and refill the gearcase with the manufacturer-specified lubricant until it flows from the vent hole.
- Install the vent and drain screws with the new washers provided in the kit. Securely tighten them.
Troubleshooting & FAQ
How do I know if this kit fits my engine?
This kit is designed for Johnson and Evinrude 35-75HP outboards from 1975–1988 with a small gearcase. The best way to confirm fitment is to check your engine's model and year against the compatibility table and cross-reference your existing part numbers with those listed in the Part Number Matrix.
What are the signs of a failing lower unit seal?
The most common signs are milky, white, or creamy gear oil (indicating water intrusion), visible oil leaks from the propeller shaft or driveshaft area, or a recurring low gear oil level. Any of these symptoms warrant an inspection and likely a reseal.
A review mentioned fit issues with a 70HP Johnson model. Is this a known problem?
While this kit is specified for a wide range of models, including 70HP variations, manufacturing tolerances on older engines can sometimes cause minor discrepancies. We have noted this feedback but have extensive verification showing compatibility. Always verify your engine's specific model and year, and check that it uses OEM part number 0396355, to ensure the best fit.
How often should lower unit seals be replaced?
There is no fixed replacement interval, but it's good practice to inspect for leaks annually when changing the gear oil. Many owners perform a preventative reseal every 5-7 years, or immediately if any signs of water intrusion or oil leakage are found.
Are all the necessary O-rings and gaskets for a full reseal included?
Yes, this kit is comprehensive and includes the primary driveshaft and propeller shaft seals, O-rings, gaskets, and drain screw washers needed for a standard lower unit service, as detailed in the "What’s in the Box" list.
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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