130 HP Johnson

[TD_Maker]

New (to me) Johnson 130 hp motor. Has an alum. prop (15 x 17) that is turning about 5800 with two people aboard and full fuel on a 20ft Aquasport. I want to purchase a SS Prop. <br /><br />Question: Would I purchase another 15 x 17 inch prop in Stainless? Most of the SS props I have seen are something like 14 3/4 x 17. Does this make a difference?

 

[bluewater19]

Re: 130 HP Johnson

Nope<br /> Worry about the pitch. A 1/4" difference won't hurt a thing. You will find many props with the same pitch and small variations in Diameter.

 

[dpfrost]

Re: 130 HP Johnson

TD<br /><br />If you want to gain alittle more speed you can go with a ss 19 pitch if you want. It might drop your rpms dowm alittle but since your running that high it propable wouldn't hurt. But if your satisfied with the speed your at kept the 17 but definatly go with ss. The diameter of the pitch isn't going to hurt by going with the 14 3/4 or smaller 14 1/4 or 1/2.

 

[walleyehed]

Re: 130 HP Johnson

Better stay with the RPM you have now...nothing less. Raising pitch in an effort to increase speed is the last thing we do in setting up a rig.<br />SS will drop your RPM generally around 100RPM in the same pitch, and if possible, stay with the same diameter so we have the option of raising the engine if needed to get some RPM back...that's where diameter DOES make a difference.

 

[TD_Maker]

Re: 130 HP Johnson

Walleyehed,<br />Thanks for the info. Like I said, I am happy with the RPMs and even the speed of my boat (I am running at 39 knots GPS at WOT)which is not too bad for a 20 ft CC boat. I just want to change to a SS Prop, and I was wondering about the difference between a SS and Alum prop.<br /><br />I am not a new boater, and I have always had SS Props; however, I have never replaced an alum. prop with a SS prop in exact sizes. What will happen to the RPm's if I purchase an exact size replacement in Stainless?

 

[TD_Maker]

Re: 130 HP Johnson

Walleyehed,<br />One other thing. Don't look too serious at Florida. Property values have hit the roof, and most of us locals are looking to get out now. Hurricanes are a constany worry. I lost my home last year.