The Mercury Racing 500R UltraLock Propeller Hub Kit, part number 8M0217764, is a brand-new Genuine Mercury Racing OEM heavy-duty hub assembly designed for the factory 1.50-inch propeller shaft used on Mercury Racing 500R outboards.
The 4.6 Liter V8 500R uses a much larger propeller shaft and gearcase than conventional Mercury applications, so it requires a dedicated hub system. The 8M0217764 UltraLock kit is designed to adapt compatible Flo-Torq hub-equipped propellers to the 500R while providing the strength, retention hardware and sealing arrangement required for this high-output platform.
Designed for the Mercury Racing 500R
The 4.6 Liter Mercury Racing 500R uses a 1.50-inch propeller shaft and large 5.9-inch gearcase. This configuration is substantially different from the more common 1.00-inch and 1.25-inch Mercury propeller shaft systems.
The UltraLock hub is built specifically around this larger shaft diameter and the torque produced by the 500R. It should not be replaced with a conventional Flo-Torq hub kit simply because the propeller itself accepts a Flo-Torq-style hub.
Flo-Torq Propeller Applications
Mercury Racing specifies the 8M0217764 UltraLock Hub Kit for compatible Flo-Torq hub-equipped propellers installed on the V8 500R.
Common applications include:
Mercury Racing Ventera – four-blade high-performance propeller designed for strong acceleration, handling and carrying ability.
Mercury Racing MAX5 – five-blade performance propeller commonly used on fast, heavily powered hulls requiring excellent grip and acceleration.
Other compatible Flo-Torq hub-equipped propellers may also use the 8M0217764 kit when specified by Mercury Racing. Always verify the propeller family before installation.
Heavy-Duty Stainless / Steel Construction
The 8M0217764 UltraLock is a heavy-duty metal hub system designed for the demanding torque and thrust loads produced by the Mercury Racing 500R.
Its robust construction makes it appropriate for high-performance offshore, catamaran and performance V-bottom applications where propeller loading changes rapidly during acceleration, trimming, and high-speed operation.
The system also uses a dual-nut retention arrangement, with a jam nut and lock nut helping secure the propeller assembly on the 1.50-inch shaft.
Labyrinth Seal Ring
The 500R hub system also uses a labyrinth seal ring designed around the larger 5.9-inch gearcase.
This ring is part of the complete installation system and should not be treated as an optional spacer. It helps complete the interface between the propeller and the 500R gearcase.
That is another reason older Mercury hub hardware should not be mixed into the 500R installation.
Fits Mercury Racing 500R
The Mercury Racing 8M0217764 UltraLock Propeller Hub Kit is designed for: Mercury Racing 500R outboards with the factory 1.50-inch propeller shaft.
Fitment should still be confirmed by the actual engine, gearcase, and propeller model, because different propeller families can require different hardware.
Buckshot Racing #77 Installation Tech Tip
Before installing the propeller, inspect the 1.50-inch propeller shaft splines, thrust surfaces, hub components and propeller bore for damage or contamination.
Confirm that the correct thrust hardware and labyrinth seal ring are installed in the proper order. Do not mix washers, nuts or hub pieces from unrelated Mercury propeller systems.
Follow the current Mercury Racing installation instructions and torque sequence for the UltraLock dual-nut system. Correct engagement and tightening are especially important on a 500R because of the torque and propeller loads involved.
After initial operation, inspect the propeller and mounting hardware as part of normal high-performance maintenance.
Genuine Mercury Racing OEM from Buckshot Racing #77
The Mercury Racing 8M0217764 UltraLock 500R Propeller Hub Kit offered by Buckshot Racing #77 is a new Genuine Mercury Racing OEM assembly, not an aftermarket replacement.
It is the correct heavy-duty hub solution for compatible Ventera, MAX5, and other Flo-Torq hub-equipped propellers installed on the Mercury Racing 500R 1.50-inch propeller shaft.
Important: CNC Cleaver Propellers Use a Different Kit
The Mercury Racing Outboard CNC Cleaver is an important exception. For compatible CNC Cleaver propellers on the 500R, Mercury Racing specifies hardware kit 8M0179579 rather than the complete 8M0217764 UltraLock hub assembly. For Mercury Racing Outboard CNC Cleaver installations, use 8M0179579 instead.
Contact Mike Hill at +1-714-697-1716 for tech support.