what is my pitch?

[out2c]

I have a 1965 johnson 75hp outboard. Couldn't find any numbers on the prop, removed the prop and these numbers were on the lower unit...307089?
...help thanks jeff

 

[steelespike]

Re: what is my pitch?

Sounds like a lower unit part number. 65 brochure lists a 101/4 (diameter) X 10"(pitch) as standard.There are about 5 optional sizes depending on the application.Give us the details of your boat/motor someone may have a similar setup.
your best bet is to take it to a prop shop and have it measured.

 

[out2c]

Re: what is my pitch?

1969 wacanda husky...1965 johnson super sea horse out board 75hp about all the info i know now. thank again jeff

 

[steelespike]

Re: what is my pitch?

Most of us wouldn't know a Waconda Husky if we fell over it in the dark.
Do you know how long,bow rider?closed bow,fiberglass,Aluminum,Deep V, shallow V,flat bottom,Big beefy deep water boat or delicate low speedy style?etc.Still would be only a best guess.Actual prop size is really the best way to start.Then you need a test run with the max rpm and speed.You shouldn't routinely run the boat untill you know that it is operating within its recomended rpm range.A tinytach is reasonable and easy to install or you might be able to borrow a shop tach.