Identifying Prop Pitch

[RandyEvers]

I have a 1973 Merc 200 (20hp). Bought it used a few months ago and it has a 3-blade prop on it. I have a box from the seller with 2 extra props, one of which is a 2-blade prop.

I obtained on ebay, an owner's manual for the 73 Merc 200 and the tables on the front show that for 12' to 15' boats, the recommended prop (and the prop that was installed by the factory, new) is a 2-blade, 11 pitch prop. How can I tell if the 2-blade extra prop is the correct 11-pitch prop.????????????

 

[Art Bernard]

Re: Identifying Prop Pitch

The pitch should be stamped on the prop. If there is no stamping than you'll prolly have to take it to a prop shop and ask them.

Art

 

[steelespike]

Re: Identifying Prop Pitch

Look for numbers near the base of the blades or under the prop nut.
Best way to tell the best prop for your application is to get a tach(tinytach) will work and a gps.
Do some test runs with each prop.Get us the prop size and the max rpm and speed.
If no prop numbers a prop shop can measure it for you.With the prop numbers and the rpm and speed we can help decide if you have a prop that will work.
Prop sizes based on boat size are just rough starting points as there can be vast differences
between various boats of similar size.