11-Inch Propeller Safety Guard for 25–35 HP Outboard Motors | SeaSierra

Protect your outboard propeller with this bright orange, bolt-on 11-inch propeller safety guard for 25–35 HP outboard motors. The one-piece guard helps make the propeller more visible and is designed to clear propellers up to 10.5 inches in diameter when correctly positioned and installed. Always confirm the guard size, propeller clearance, engine model, and gearcase configuration before installation.

• Manufacturer: SeaSierra
• Guard type: One-piece bolt-on propeller safety guard
• Guard diameter: 11 inches
• Recommended engine range: 25–35 HP outboard motors
• Maximum propeller diameter clearance: Up to 10.5 inches
• Color: Safety orange
• Material: Rigid polypropylene plastic with 304 stainless-steel hardware
• Package weight: Approximately 1.998 kg

Compatibility

This 11-inch propeller guard is intended for selected 25–35 HP outboard applications from brands including Mercury, Yamaha, Honda, BRP, and Suzuki. Compatibility depends on the exact engine model, year, gearcase, shaft configuration, propeller size, and available mounting surface. Confirm the model-specific fit and maintain equal clearance between the guard and the rotating propeller before use.

Important: Big Foot, Command Thrust, and High Thrust gearcases generally require the larger 13-inch guard rather than this 11-inch version. Do not use this guard if the propeller or gearcase cannot maintain safe clearance inside the guard.

Package Contents

• 1 × 11-inch safety-orange polypropylene propeller guard
• 8 sets × mounting bolts and associated hardware
• 1 × drill

Key Features and Benefits

• Bright safety-orange color improves propeller visibility from a distance.
• Rigid polypropylene construction is lightweight, water-resistant, and suitable for marine use.
• One-piece bolt-on design provides a straightforward installation format for compatible outboards.
• Designed for propellers up to 10.5 inches in diameter when the correct clearance is confirmed.
• Helps shield the propeller area and can make the rotating propeller easier to identify during low-speed maneuvering or towing operations.
• Includes mounting hardware and a drill for the installation process.

Installation Instructions

Tools and preparation:

• Use the included drill with an appropriate 5/16-inch drill bit.
• Use the included mounting hardware according to the applicable mounting layout.
• Before drilling, verify that the guard is centered and that the propeller has even clearance from the guard throughout a complete rotation.

Installation steps:

1. Place the propeller guard beneath the cavitation plate and position it so the guard is centered around the propeller.
2. Check the clearance between the guard and the propeller at every point of rotation. The propeller must not contact the guard.
3. Position the guard as far forward on the cavitation plate as the engine and mounting layout allow.
4. For 9-, 11-, 13-, and 14-inch guard installations, remove the trim tab beneath the cavitation plate if it interferes with the guard or mounting position.
5. Mark the mounting holes, drill through the cavitation plate and guard as required by the mounting layout, then install the bolts, washers, and Nyloc nuts. Keep the fasteners loose until the guard is correctly aligned.
6. Install the lower mounting fastener through the lower skeg where required by the installation layout, then tighten the nut securely.
7. Recheck the guard alignment and propeller clearance, then tighten all cavitation-plate and lower mounting fasteners evenly.
8. Rotate the propeller by hand with the engine off to confirm that there is no contact or interference before operating the boat.

Safety note: Follow the engine and guard manufacturer's installation instructions. If drilling, alignment, or clearance measurements are uncertain, have the guard installed and checked by a qualified marine technician. Never inspect or adjust the guard while the engine is running.

Maintenance

• Rinse the guard and mounting hardware with fresh water after use in salt water.
• Regularly inspect the polypropylene guard for cracks, distortion, or impact damage.
• Check all bolts, washers, and Nyloc nuts for looseness or corrosion before operation.
• Replace the guard or damaged hardware if propeller clearance can no longer be maintained.

Frequently Asked Questions

What propeller size does this guard accommodate?
This 11-inch guard is designed to clear propellers up to 10.5 inches in diameter, provided the exact engine and gearcase installation maintains safe clearance.

Is this guard suitable for all 25–35 HP outboards?
No. Horsepower alone does not confirm fitment. Check the exact engine model, year, gearcase configuration, propeller diameter, and mounting surface before installation.

Can it be used on Big Foot, Command Thrust, or High Thrust gearcases?
These larger gearcase configurations generally require a 13-inch guard. Confirm the correct guard size for the specific engine before purchase or installation.

Is mounting hardware included?
Yes. The package includes the propeller guard, eight sets of mounting hardware, and one drill.

Does the guard replace the need for normal propeller inspection?
No. Inspect the propeller, guard, mounting hardware, and clearance regularly. Stop using the boat if the guard is damaged, loose, or contacting the propeller.