Alum vs Stainless steel prop

[nightvision]

Hi all,<br />Please explain to me the need for stainless steel prop. What is the advantage (pro/con) and why would you need one over an aluminum one.<br /><br />Thanks.

 

[Dhadley]

Re: Alum vs Stainless steel prop

A ss prop holds its shape better (less flex) and can hold more technical shapes. They're tougher so they last a long time. Some feel that if you hit something a ss prop will do damage to the gears. Its never happened to me and I've hit some stuff pretty hard. The rubber hub should cushion the blow, thats what its for.

 

[craze1cars]

Re: Alum vs Stainless steel prop

Stainless is much stronger, therefore the props are made with thinner blades which cut through the water with less resistance. This results in higher top speeds and faster accelleration. Aluminums are cheap in the short term, but very soft, so if you bump a rock it's basically done and needs replacement. A stainless can take multiple rock bumps and get nothing more than a small nick. But the stainless will transfer more stresses to the inner guts of the drive and can possibly do gear and shaft damage, but most come with hubs that actually shear and spin so it takes the brunt of the stress to help prevent the internal drive damage.<br /><br />Higher horsepower boats get more noticable performance benefits from stainless than smaller motors.<br /><br />It's all give & take. For my 3.0 Mercruiser, I run aluminum.

 

[Richard Petersen]

Re: Alum vs Stainless steel prop

Buy 3 Alum for 1 SS. 5% difference in top speed really worth it. Alpha Drives with a hard dog clutch type of shift like the much lighter Aluminum props. Cone clutch smoothies like either.

 

[moderator1]

Re: Alum vs Stainless steel prop

3 "good" alum., or just 3 "cheap" alum.?????<br />Is it worth 5% gain???? Yes, no question to me.

 

[QC]

Re: Alum vs Stainless steel prop

Aluminums get noticable damage if you look at them crosseyed . . . I have beat on both and I can do a quick repair on a stainless if I didn't hit somthing too dang hard, somtimes aluminums break while you're fixing them. I have run stainless on both Alphas and Bravos with great success. Hit pretty hard once with the Alpha and was able to repair enough to finish the weekend without even removing from the drive and kept the boat in the water. I have never hit hard enough to spin a hub with either, and I have had some good whacks . . . I have had aluminums get bent after hitting some weeds that a stainless would have simply chopped up.<br /><br />Quick note, sometimes aluminums actually have better hole shot due to the flex. What power and boat combo are we talking about here?

 

[dutch135]

Re: Alum vs Stainless steel prop

Myself I am running a 180 Crownline with the 4.3LX 4bbl.. I think i'm off as far as prop goes.. I'm running about 4800 RPM WOT (too much, right?)... this is with a 21 aluminum prop. I was thinking about a new prop, and if I went SS, how would you recommend? Stay with 21, or change pitch?<br />thanks

 

[Dhadley]

Re: Alum vs Stainless steel prop

Dutch, theres a 23 Turbo on Ebay now.

 

[dingbat]

Re: Alum vs Stainless steel prop

I changed out from aluminum to SS last summer and probably would not do it again. Like stated earlier I could buy 3 good aluminum props for the price of a ss and my top end only changed from 32 kt.s to 34 kt.s so I don’t see any real valve in the ss prop. Granted they may last longer if abused but my idea of slim water is 4’ deep so no hitting rocks and stuff for me really isn’t a concern to me. I latterly wore out my last aluminum prop.<br /><br />Anyhow, it looks pretty on the back of the boat.