Grease, Gearcase and Hydraulic Steering Oil

Proper lubrication of your outboard gearcase and steering system is essential to prevent costly breakdowns and ensure peak performance. Using a specific outboard oil for marine engines protects gears from corrosion and wear, even under extreme conditions. A quality marine grease, whether for mechanical or hydraulic steering, ensures smooth and precise steering, preventing friction and sudden lock-ups.

Choosing the right lubricant depends on the type of engine and steering system. For Evinrude, Johnson, BRP, and OMC outboards, it's advisable to use genuine or equivalent oils and greases that meet the manufacturer's specifications. An unsuitable oil can compromise lubrication and damage internal gearcase components.

A common problem is gearcase oil contamination with water, which can cause corrosion and reduce lubricating capacity. Regularly check the oil level and appearance, and replace it if you have any doubts. For steering systems, periodically grease the pivot points and linkage mechanisms to prevent oxidation and seizing.

The Nautica Basile Tip

• Visual Inspection: Always check for oil leaks from the gearcase and steering system. A leak may indicate a sealing problem.


• Scheduled Replacement: Follow the engine manual's instructions for gearcase oil replacement. Generally, an annual replacement or every 100 hours of use is recommended.


• Specific Grease: Use only saltwater-resistant marine grease for steering systems. Ordinary grease can be washed away quickly, leaving components exposed to corrosion.


• Compatibility: If you have doubts about the compatibility of an oil or grease, consult the engine manual or seek advice from a qualified mechanic.

Remember to also check the condition of the steering cables. Frayed or rusty cables can compromise navigational safety. If in doubt, replace them promptly. You might also be interested in our section dedicated to sacrificial anodes to further protect your engine's gearcase.

Can I use regular engine oil in the outboard gearcase?

Absolutely not. Engine oil has different characteristics and is not suitable for protecting gearcase gears from corrosion and mechanical stress. Use only gearcase oil specifically designed for outboards.

How often should I grease the steering system?

It depends on the operating conditions. In general, it is recommended to grease the steering system at least once a year, preferably before the winter season. If you frequently navigate in saltwater, grease it more often.

How do I know if the gearcase oil is contaminated with water?

Oil contaminated with water takes on a milky or foamy appearance. In some cases, rust or corrosion may be present on the drain plug. If you notice these signs, replace the oil immediately.

What is the difference between grease for mechanical and hydraulic steering systems?

Grease for mechanical steering systems is a multi-purpose, saltwater-resistant marine grease. Grease for hydraulic steering systems is a specific fluid with anti-corrosion and anti-wear properties, designed to withstand the high pressures of the hydraulic system. Do not use grease for mechanical steering systems in a hydraulic system.

Can I use regular engine oil in the outboard gearcase?

Absolutely not. Engine oil has different characteristics and is not suitable for protecting gearcase gears from corrosion and mechanical stress. Use only gearcase oil specifically designed for outboards.

How often should I grease the steering system?

It depends on the operating conditions. In general, it is recommended to grease the steering system at least once a year, preferably before the winter season. If you frequently navigate in saltwater, grease it more often.

How do I know if the gearcase oil is contaminated with water?

Oil contaminated with water takes on a milky or foamy appearance. In some cases, rust or corrosion may be present on the drain plug. If you notice these signs, replace the oil immediately.

What is the difference between grease for mechanical and hydraulic steering systems?

Grease for mechanical steering systems is a multi-purpose, saltwater-resistant marine grease. Grease for hydraulic steering systems is a specific fluid with anti-corrosion and anti-wear properties, designed to withstand the high pressures of the hydraulic system. Do not use grease for mechanical steering systems in a hydraulic system.