Propeller Safety Guard – Fits Outboard Motors 9.9-20 HP (Replaces NorthBoat 9" Yellow Cage)

Propeller Safety Guard – Fits Outboard Motors 9.9-20 HP

This yellow polypropylene propeller safety guard is designed for outboard motors from 9.9 to 20 HP. It is compatible with all major brands where the distance from the motor propeller shaft to the cavitation plate is between 4.25" and 5.5". This guard fits propellers up to 8.5" in diameter.

This part is a direct replacement for the following part numbers: NorthBoat 9" Yellow Cage, East Marine prop-guard-9, Prop Guard Marine Yellow, and Sea Sierra SP6289.

• Installation Method: Bolt-on (requires drilling) using a clamp and bolt system.
• Construction: Two-piece clamshell design with no moving parts, made from high-strength polypropylene.
• Compatibility: Fits most 9.9-20 HP models from Mercury, Yamaha, Honda, Suzuki, Tohatsu, and Johnson/Evinrude (excluding Big Foot/High Thrust models).

Compatible Engine Models

Confirm your engine model/year in the table below.

Note: Big Foot and High Thrust models require a larger 11" propeller guard.

Technical Specifications

Package Contents

• 1 x Propeller Safety Guard (9" diameter)
• Mounting hardware (bolts, washers, nuts)
• 1 x 5/16" drill bit included for installation.

Installation Guide

1. Safety First: Ensure the engine is off and disconnect the battery before starting.
2. Assemble Guard: Join the two halves of the propeller guard around the propeller unit.
3. Position Guard: Place the assembled guard onto the lower unit, ensuring it is centered on the cavitation plate and skeg.
4. Mark Holes: With the guard correctly positioned, mark the four drill points on the cavitation plate through the mounting holes.
5. Drill Holes: Remove the guard. Using the included 5/16" drill bit, carefully drill the four marked holes through the cavitation plate.
6. Mount Guard: Re-position the guard and secure it by inserting the bolts through the guard and the newly drilled holes. Fasten with the washers and nuts provided.
7. Final Check: Ensure the propeller spins freely without touching the guard. Tighten all mounting hardware securely.
8. Reconnect Power: Reconnect the boat's battery.

Troubleshooting & FAQ

How do I confirm this guard will fit my 9.9-20 HP motor? This guard fits most major brands, but you must measure the distance from the center of the propeller shaft to the underside of the cavitation plate. This distance must be between 4.25 inches and 5.5 inches. Crucially, this 9" guard is not for "Big Foot" or "High Thrust" models, which require a larger 11" guard due to their larger gearcases.

What is involved in the installation? Do I have to drill into my motor? Yes, installation requires drilling four holes into the anti-cavitation plate of your outboard motor. The guard clamps and bolts directly to the plate and skeg. A 5/16" drill bit is included in the package to perform this step.

Is this plastic guard durable enough for marine use? Absolutely. The guard is constructed from a high-strength, injection-molded polypropylene. This material is engineered to withstand impacts, protecting the propeller from underwater hazards and providing safety for people, swimmers, and marine life. The two-piece design is simple and robust, with no moving parts that could fail.

OEM vs. Aftermarket? This listing is an aftermarket replacement part (not an OEM component). We build to OEM specifications using comparable-grade materials. Production is done in an ISO9002-certified facility, and each batch is inspected for consistent performance.

How fast do you ship and how much does it cost? We offer fast global shipping—typically 5–15 days worldwide—and standard shipping is free. Expedited options are available at checkout depending on your location.

What is your warranty and return policy? This product includes a 1-year warranty against manufacturing defects under normal use. If something goes wrong, contact our support team with your order details. Returns are accepted within our standard return window (unused & in original condition); please see our policy page or reach out for instructions.

Important Notes

• Verify that the product images and specifications match your original part. If discrepancies exist—even if your model is listed—do not proceed with the purchase.
• This product is an aftermarket replacement part and is not an OEM component.
• Professional installation is recommended to ensure safety and optimal performance.

Why Choose JLM MARINE?

• Quality Assured: As a trusted manufacturer for over 20 years, we supply top marine brands globally.
• Fast Global Shipping: Free delivery worldwide in 5–15 days.
• Direct from Manufacturer: Competitive pricing without compromising quality.