MasterGuard Hub Kit 509 – 500 Series | 4.25" & 4.75" Gearcase Outboards & Sterndrives

MasterGuard Hub Kit 509 – 500 Series | 4.25" & 4.75" Gearcase

The MasterGuard 509 is a 500 Series propeller hub installation kit designed for outboards and sterndrives with 4.25" or 4.75" gearcases. It includes everything needed to mount compatible Turning Point propeller housings — hub, thrust washer, and required hardware — in a single, clean package that installs quickly and protects your lower unit from prop strike damage.

Compatible propeller housings include the Express Mach3 (RH), Express Mach3 (LH), Express Mach4 (RH), Express Mach4 (LH), and Hustler aluminum propellers. Also compatible as a hub upgrade for Solas Rubex, Michigan Wheel XHS, and Mercury FloTorq propeller housings. Always verify your specific engine and required kit number using the application chart before ordering.

Key Features

• Lifetime Warranty — The only hub kit in the world with a lifetime warranty. Covered for engines under 200hp with aluminum or stainless steel props, and for engines 200hp+ with aluminum props. Warranted even if the propeller housing is destroyed (consumer/normal use; excludes extreme commercial applications).
• One-Piece Construction — Marine bronze splines over-molded with glass-filled nylon eliminate the failure points common in multi-part sleeve-and-spline or pressed-rubber hub systems. No spinning, no cracking, no chatter.
• Reusable After a Prop Strike — The hub is engineered to absorb shock and protect the lower unit. In most cases it can be reused after a strike; if not, it's covered under warranty.
• Lower Unit Protection — Shock-absorbing polymer cushion reduces gear shock and helps protect the engine drive from impact damage.
• Save on Replacement Props — Because the hub stays with the engine, customers only need to replace the propeller housing after a strike — saving up to 33% compared to replacing a full prop assembly.
• Broad Engine Compatibility — Fits Evinrude, Honda, Johnson, Mariner, Mercury, MerCruiser, Nissan, OMC, Parsun, Suzuki, Tohatsu, and Yamaha outboards and sterndrives. Consult the application chart for your specific engine.
• Easy Installation — Minimal parts and clear step-by-step instructions make installation straightforward.

What's in the Box

Hub, thrust washer, and all required installation hardware.

Other 500 Series Hub Kits

Not sure if the 509 is the right kit for your engine? Compare with other 500 Series options: Kit 500, Kit 501, Kit 502, Kit 503, Kit 504, Kit 505, Kit 506, Kit 507, Kit 508. Always confirm fitment using the application chart.

Parts Desk Insights

Best Use Case: Any customer purchasing a compatible Turning Point propeller housing who needs the correct hub kit for their engine. Also a strong recommendation for customers upgrading from OEM or competitor hub systems (Solas Rubex, Michigan Wheel XHS, Mercury FloTorq) who want lifetime warranty coverage and better lower unit protection.

• Always sell the hub kit with the prop — this is a required component, not an optional add-on. Confirm the customer has the correct kit number for their engine before completing the sale.
• Warranty is a strong selling point — no other hub kit on the market offers a lifetime warranty. Lead with this when a customer is comparing options or hesitating on price.
• Prop strike scenario — remind customers that after a strike, they may only need to replace the propeller housing, not the entire assembly. The hub is reusable in most cases and warranted if not — this saves real money over time.
• Cross-compatibility — the 509 also works as a hub upgrade for Solas Rubex, Michigan Wheel XHS, and Mercury FloTorq housings. Useful when a customer is switching prop brands but wants to keep the MasterGuard hub system.
• If unsure which kit number fits the customer's engine, direct them to the application chart or compare with Kit 500 through Kit 508 for the correct match.