Prop is too short, splines are. Showing

[sprizzel]

I bought a new prop with a pressed in hub for my mercury 75 hp. The other mercury/quicksilver interchange hubbed prop work fine because of the added 1/2 “ of the insert.

When I place this other prop on there is about an inch of spline showing and so I am unable to tighten the prop down.

I saw there are castle nuts but I fail to see how this would help as it would only tighten down and still not reach the prop. I think I and missing the mechanics of the castle, or is there any other solution as in a washer/spacer.

Thrust washer is installed correctly as well.

 

[airshot]

Make model # and pics...otherwise we can only guess.

 

[sprizzel]

18 ft part barge 75 hp mercury outboard 2024

 

[Cortes100]

On my 60 HP I run Merc props with the REflex hubs. I tried an aftermarket prop with the built in rubber hub. It needed a special thrust washer meant for that prop (does not come with new prop). The thrust washer from the reflex will not work with the built in hubs. With the limited info sounds very much like you need a different washer.