Aluminum to stainless

[alesha00]

I am currently boating a 2001 Alumacraft tournament pro 175cs with a 150 evinrude (2002) with a 15x17 aluminum prop (unknown manufacturer). I get about 5250 RPM at WOT with about 45 MPH with light gear and a full tank. I want to switch to a stainless prop and are unsure of what pitch to get. I have been viewing the props used on alumacrafts with evinrude motors and it seems like some are 17 degrees and others are 19degrees. Any recommendations?

 

[Bondo]

Re: Aluminum to stainless

I am currently boating a 2001 Alumacraft tournament pro 175cs with a 150 evinrude (2002) with a 15x17 aluminum prop (unknown manufacturer). I get about 5250 RPM at WOT with about 45 MPH with light gear and a full tank. I want to switch to a stainless prop and are unsure of what pitch to get. I have been viewing the props used on alumacrafts with evinrude motors and it seems like some are 17 degrees and others are 19degrees. Any recommendations?

Ayuh,... Welcome Aboard,... Why do ya gotta go SSteel,..?? It's Much less forgiving when real estate is encountered..

'n,... props are measured in Inches, not degrees...

 

[alesha00]

Re: Aluminum to stainless

I frequently use the boat in an area where hitting a rock is a possibility. While I know that an aluminum prop will give (break), it would be nice to have the stainless bend (mostly) and allow me to return to camp. I also am believed that the stainless prop is slightly more efficient and will give me more umph.

 

[Bondo]

Re: Aluminum to stainless

I frequently use the boat in an area where hitting a rock is a possibility. While I know that an aluminum prop will give (break), it would be nice to have the stainless bend (mostly) and allow me to return to camp. I also am believed that the stainless prop is slightly more efficient and will give me more umph.

Ayuh,... A prop strike on a SSteel wheel transfers all that bad energy into the motors splines, 'n gears...

Boatin' where there's a High chance of a prop strike is Not where a SSteel wheel oughta be...

That said,... Buy a prop that allows the motor to reach it's Rated Wot rpms... Which you haven't mentioned...

 

[tpenfield]

Re: Aluminum to stainless

I have been viewing the props used on alumacrafts with evinrude motors and it seems like some are 17 degrees and others are 19degrees. Any recommendations?

Prop pitches are in "inches of travel", not "degrees".

You will like a stainless prop over the aluminum. If you use the "prop slector" app that is part of many propeller web sites, that might get you dialed into the right pitch.. It should be close to what you have in the aluminum.

 

[alesha00]

Re: Aluminum to stainless

from what I can find the manuf. spec for max rpm are 5250

 

[jimmbo]

Re: Aluminum to stainless

When I switched to SS, also on a Johnrude 150 I dropped 1 inch in pitch. I went with a RAKER and was able to raise the engine up a couple of bolt holes on the transom. Net gain was 5 mph, engine did not blow out in turns and boat rode higher in water and could be trimmed out further.
A few years later I was running my I/O with Stainless. I was only going about 21-21mph when it made several impacts with rock ridges. The tips of all 3 blades were bent, 2 of the blades were torn, the skeg of the drive had a twist in it but only a very small chunk missing. The Propshaft was bent and needed to be replaced. Do I blame the SS for the bent shaft? You Betcha!