Aluminum Propeller AMITA3 10.5X11 Right Hand 4211-105-11

Function and Technical Context

The AMITA3 aluminum propeller with specifications 10.5x11 inches and right-hand rotation is the final element in the outboard motor drivetrain: it converts the crankshaft torque, transmitted through the gearbox, into hydraulic thrust propelling the vessel forward. Manufactured from high-strength aluminum alloy, it is designed specifically for 4-stroke outboard motors of 25 and 30 HP from Johnson and Evinrude brands, where the geometry of its three blades and the 11-inch pitch directly determine the engine operating regime, fuel consumption, and cruising speed. An inadequate propeller—due to incorrect pitch or structural damage—subjects the motor to over-revving or under-revving, which accelerates wear of bearings, seals, and gears in the transmission box. Precise adjustment of diameter and pitch ensures that the engine operates within its design RPM band, maximizing propulsive efficiency in semi-rigid boats, inflatable vessels, and small recreational speedboats.

When to Replace This Part?

The clearest signs that the propeller requires replacement are: unusual vibrations transmitted through the steering arm or transom, noticeable loss of top speed or acceleration response, and persistent cavitation phenomena caused by bent, eroded blades or leading edge deformation following contact with submerged objects or rocky bottoms. It is recommended to perform visual and tactile inspection of each blade at the beginning and end of each boating season, as well as after any grounding or impact, since even slight deformation generates sufficient dynamic imbalance to deteriorate the propeller shaft bearings and the seals of the gearbox. Replacing the propeller preventively at the first sign of deformation avoids costlier transmission breakdowns and ensures you won't be stranded far from port.

Compatible Johnson/Evinrude Engines

Equivalent Manufacturer References