Prop shaft castle nut

[LakeOntario270]

I pulled my cruising prop off today (Catalina 270) and the shaft key was totally destroyed. I went to Catalina Direct for a new key and they have a package consisting of a brass castle nut, shaft key, and cotter pin. Why did they use brass and not stainless?

 

[Meriachee]

I got the new shaft kit from them and it had all stainless parts. Might be an idea to give them a call.

 

[centerline]

hopefully you mean bronze rather than brass....
its common for stainless on stainless to cause galling, in which case it damages the threads on the shaft and may need to have the nut cut off.
the bronze nut against the bronze prop will have no dissimilar metal issues so will have no corrosion between the two and be less likely to become loose over time.
either bronze or stainless can be used, but if you have ever experienced the galling, you will prefer the bronze from that point on..

 

[Meriachee]

Stainless. Bronze gets brittle at -40.