In the propeller hubs product group, you will find replaceable hubs that are installed inside the propeller: Quicksilver's Evinrude/Cobra/SX 4-propeller hub, Evinrude 1-propeller hub, Honda 1-, 2- and 3-propeller hubs, and Mercury 2-propeller hub.
The hub is a rubber or plastic structure inside the propeller that flexibly transmits force from the shaft to the propeller blades — this flexibility also acts as mechanical protection: if the propeller hits the bottom, a rock, or other obstacle, the hub momentarily slips on the shaft and prevents the impact from being transmitted directly to the gearbox or engine. Without a functioning hub, bottoming could cause significantly more expensive gearbox damage.
The hub wears out over time during normal use, and especially after harder bottom contact, the rubber can loosen or tear — a sign of a worn hub is typically the feeling that when you apply the throttle, the boat does not accelerate as expected, even though the engine is spinning normally, because the power is not fully transmitted to the propeller.
The choice of hub is always strictly engine brand and propeller blade count specific — Evinrude, Honda, and Mercury each use their own hub designs, and hubs cannot be interchanged from one brand to another. Check your propeller manufacturer and blade count before ordering, and consider purchasing a spare hub if you often boat in shallow or rocky waters.
A worn hub can often be detected by visually inspecting it when removed — cracks, hardening, or obvious wear on the rubber part are signs that it needs to be replaced before the problem becomes apparent while driving. Keep a spare hub with you if you often boat in unfamiliar or shallow waters where the risk of bottoming is higher.
Keep the old hub as a reference until you are sure the new part fits — this will make it easier to identify and return a possible incorrect order before you have time to install the wrong part.
If necessary, seek advice on identifying the correct hub if the propeller marking is worn or unclear — installing the wrong hub can cause vibration or inefficiency, which can easily be confused with other faults.
Compare the price of the hub as an original part and a compatible alternative — both will work, but the original part is often the safest choice for perfect compatibility.
Write down the date you replaced your bottom bracket so you know when to check it next time without a separate note or guesswork.
Ask for advice on choosing the right hub model if your propeller is a rarer or older model version from the range.