which prop

[chaldon3]

hi there guys can you help advise which propeller would be the one to use.
no info on old propeller.
however on new propeller is stamped13.5x8.75. also796 21822
many thanks for your advise garry.
lister petter ac1 at 3600rpm 6.5hp
18ft gpr boat som italian gear box 2:1

 

[chaldon3]

hi there any one help on this subject. kind regards garry.

 

[Kawasaki]

hi there any one help on this subject. kind regards garry.

chaldon, it appears you have a displacement vessel, which will do 8 kts max, ish
So- I would take the prop /props to Castle Marine in Caernarfon, which must be close to you
The 2; 1 reduction is fairly standard
6.5 hp will give you 'cruising' at 3200 rpm of 5 kts I would imagine for an 18 footer
I ain't no expert Mate, just a good guesser!
Guys in Caernarfon will advise, I reckon

 

[chaldon3]

hi Kawasaki thank you for your reply. good idea only 30 mins away. regards garry.