Omc Prop pitch help

[landslr]

The sterndrive on my Starcraft is a 1989 Cobra 2.3L 128hp. The chipped prop currently on the unit is 13.75 dia and 15 pitch. OMC p/n 391198. When I look at the OMC sterndrive applications, that prop is std on a 19-22' boat. The prop for a 17-20' is 13.25 diam and 17 pitch OMC p/n 391199. Now I am confused at to which prop I should order as a replacement. Help !!

 

[jimmbo]

Those charts are only a guide, and not always accurate. What RPM was the current prop getting at WOT?

From what I could find the WOT range is 5200 - 5600 rpm

 

[landslr]

I don't know any of the performance numbers. I just bought the boat and know I need to replace the prop. I will have the current prop repaired and use as a spare. I was just going to order a replacement but after looking at the charts, I'm not sure if that is what I need.

 

[jimmbo]

Well run the repaired prop to see what RPMs you get. Hopefully the rebuilder does a good job and the prop is close to what it originally was in regards to cupping and blade shape.