SS prop

[scs1080]

I just changed out my alum. prop for a SS Rature prop. Evey thing works fin but it seem that my engine is running a lot louder. I think I am running the same rpms a the same speed but i dont remember the number exactly. Is this common or should i be checking into it futher. The new SS prop is the same size as my alum but the ss prop does have more rake but the pitch and dia. are the same.

 

[WillyBWright]

Re: SS prop

A Stainless prop of the same pitch may run a few more RPMs than an aluminum. Blades are thinner and they slip thru the water easier. It's rarely more than a hundred RPMs or two, but that might get a motor into an RPM range that produces a bit more noise.

 

[tommays]

Re: SS prop

scs<br /><br />your current WOT is the only thing that will really tell how the prop is working on your setup<br /><br />here is some good reading about props<br /><br /> http://www.mercurymarine.com/everything_you_need_to_know_about_propellers5 <br /><br />tommays

 

[marlinempress]

Re: SS prop

I was under the impression SS props slipped less than aluminum props due to the superior strength, they don't flex as much as the aluminum props. Correct me if I'm wrong, but wouldn't that mean the engine sees more of a load, therefore the rpms should go down a little?

 

[WillyBWright]

Re: SS prop

Only on acceleration or under heavy load. Once on plane, the stress on the blades reduces drastically. Most of the flex then comes from rapid acceleration and deceleration such as when you hit a wave. Otherwise the props aren't flexing much then.

 

[walleyehed]

Re: SS prop

I was under the impression SS props slipped less than aluminum props due to the superior strength, they don't flex as much as the aluminum props. Correct me if I'm wrong, but wouldn't that mean the engine sees more of a load, therefore the rpms should go down a little?

This is most often true due to SS props usually being more efficient, and most times have more bite.

 

[scs1080]

Re: SS prop

Does anyone know what the WOT should be on 2004 Merc 3.0l inline 4 cyl. I cant find what it should be

 

[tommays]

Re: SS prop

scs<br /><br />4800 rpm <br /><br />i have a 3.0LX and you realy want to pick a prop with your normal load of people and stuff to get the best results.<br /><br />i use my boat the most with 4 or more people on board and have to run a 15 x 17 prop which is small but its the only way the boat will come on plane easely with my normal crew and stuff<br /><br />every boat and owner is different so it takes a lot of trail and error to find the best result<br /><br /><br />tommays

 

[bolo789]

Re: SS prop

hey tommay what kind of boat you have i have a 15 x 17 ss prop i ant to install on my sea ray220 da boat weight about 45 to 5000 lbs

 

[tommays]

Re: SS prop

bolo<br />maxium 2000 SC with a 3.0 which is to diffferent from your boat to even make a WAG<br /><br />really bolo as is said before only trying the boat in real use is going to tell but the worst the 15x17 is going to do is be to small and you wont no till it gets wet<br /><br />tommays

 

[scs1080]

Re: SS prop

At wide open throttle running 45mph i am only @ about 2500. That is the same rpm i was running with the factory alum prop. Is that bad that they are so low

 

[tommays]

Re: SS prop

scs <br />i can say for sure that your tack is reading way to low .<br /><br />one thing may be that it has a 4,6,8 cylinder switch that is in the worng place or it could just be bad.<br /><br /> but getting it to read the correct RPM is the next step.<br /><br />tommays