prop on 40hp Evinrude

[casracing]

The prop on my motor has some nicks and scrapes and I was thinking about replacing it. My question is: 1) Can I make my poontoon handle better by changing the prop? <br />2) what is the difference between Stainless and aluminum? <br />3) Do I have to go back to the orginal prop size? It is a 12x1/2x13 and what do these numbers mean <br />All I would like is a little more power and handling. At wot it runs in 4000-4500rpm range. Any help would be appreciated

 

[Solittle]

Re: prop on 40hp Evinrude

You will get better response by posting this in the outboard section. Having said that - <br /><br />1. Minor nicks on a prop can be filed.<br />2. There is a diffenence between al. and stainless props of the same diameter and pitch but would not be noticable in a pontoon boat.<br />3. The 12 1/2" is the diameter of the prop. The 13" is the forward movement of the prop in one revolution with no slip due to the fluid nature of the water. A 12" prop would move you 12" and a 19" prop would move you 19". An engine has to work harder with a higher pitched prop and will therefore turn less rpms and vice versa.<br />4. You need to check your manual for the WOT rpm rating for your engine. 4-4,500 rpm is to low. Alower pitched prop will bring the rpm up. Check the red Search at the top of the page for further detail.