How to determine this prop pitch.

[Nandy]

I have a prop with no marking whatsoever. How can I determine the pitch on it? Also, the motor I bought had that prop and another prop that is painted in similar color than the motor. I guess that is the original prop. It is a 13 1/4 x 17. Can anyone confirm is that is the prop that comes with the motor. It is a 70 hp 1975 evinrude.
Thanks!

BTW, here are some photos of the unmarked prop. If you look at it you can see that it has a little crack in the inside of the prop next to the hub.

 

[Silvertip]

Re: How to determine this prop pitch.

Only a prop shop can tell you for sure what pitch is on any prop unless it is labeled. They use a pitch block to determine pitch -- you cannot measure it. Also understand that there is no such thing as a standard prop on mid-range and higher HP motors and in fact the motor is shipped without one. The reason is a pontoon, work boat, or barge takes an entirely different prop than a fishing boat. The selling dealer normally works with the buyer to ensure the proper match is installed as the engine manufacturer has no idea on what type of boat the engine will be installed on.