Prop question need help

[Marcusp]

I have a 1977 evinrude 140 what is the best size prop for this motor it's on a 17 ft fish and ski

 

[steelespike]

Re: Prop question need help

Welcome,please read "read this first" at the top of the prop main page.
Try to get us as much info as possible.Present prop size is usually under the prop nut.

 

[Marcusp]

Re: Prop question need help

Welcome,please read "read this first" at the top of the prop main page.
Try to get us as much info as possible.Present prop size is usually under the prop nut.

I have a 17 pitch prop on now but I can't plane out very good

 

[steelespike]

Re: Prop question need help

Prop selection depends on the boat brand,size and type.We need to know the present wot rpm and speed.By gps if possible.
Some folks would think 15 seconds to plane is not very good others a minute or more.
With the wot rpm and speed we can put it through a calculator and find out how your setup works.
In my opinion the 17 ft should pop on plane with a 17" pitch.

 

[Marcusp]

prop

prop

I don't have a rpm gauge that works that old motor does not have a set up for rpms unless you can tell a way to geti am just going off guessing thanks for you help