Aluminum vs SS props?????

[oldsub86]

"... there were some minor dings on my stainless steel prop. I checked the runout on the shaft to see if it was bent and it checked out okay, and then I installed an aluminum prop.....
Why on earth have you put an aluminium prop on???? If you think it will 'save' the drive if you hit something again.... WRONG!!! I have seen stainless steel props wrapped up like scrap paper and thought that the inside of the drive will look like a grenade has gone off, only to find then perfect inside... Conversely, I have seen ali props with a few scratches and the gears in the drive cracked and broken beyond belief...

This thing about ali props saving drives is the biggest load of BS I have ever heard!!! And I've heard plenty...

The damage to the internals of the drive on striking something is more in the lap of the gods than what prop you've got on....

Chris....... "

Ok, borrowed from another thread.

What say you all? I Chris right or not???

Randy

 

[jopes]

Re: Aluminum vs SS props?????

from what I have read a SS prop has no real advantage unless your constantly going 50 plus.

 

[fishndirk]

Re: Aluminum vs SS props?????

First off, I run a ss prop on a 20hp outboard and I definately have noticed the difference over the factory aluminum. Not only does it respond better to throttle changes but in a night of fishing where I run 20-30miles I notice a difference is gas usage because the ss cruises better at the same load that the al did. Secondly, there are a lot more factors that go into how much you will beat up a prop besides just al or ss. I had 2 friends that both ran 25hp tohatsus, one a 4 stroke, the other a 2 stroke. The guy with the 4 stroke barely ever put any hours on his boat but his ss prop was all banged to crap after 4 years. My friend with the 2 stroke 25hp had the same exact ss prop on his but this guy is a coon a** from hell. Jumpin beaver dams and hitting logs all the time. His prop is now older than the other guys but its still in tip top shape. Why? Could be gear ratio between 2 and 4 stroke. One has more MA between the drive shaft and prop shaft. Could be luck? Skill? Who knows, too many factors. Point being, you can't predict on this. But when it comes to performance you can do the numbers. Steel has a stronger molecular structure than aluminum. That is a fact. The benefits derived from that are less noticeable at lower hp motors but become more noticeable as hp goes up. Bottom line-not worth arguing about.

 

[Star]

Re: Aluminum vs SS props?????

Ditto.. ditto.. ditto to fishndirk,
My motor performance improved accross the whole band when I installed a 9 1/4 x 11 3 blade SS. I know that your head can fool you into thinking that extra money you spent actualy did some good, but I too can see it just in fuel use.
The Gods do play a roll in your prop life, as to your own judgment. Sticks and twigs are more forgiving than rocks!!!

 

[spdracr39]

Re: Aluminum vs SS props?????

I like Stainless because it is pretty

 

[Texasmark]

Re: Aluminum vs SS props?????

SS has better performance and is more rugged. Agree on whether or not it may cause you to loose your LU. Really that is what the slip hub is for and they are in both material props. The newer props with interchangeable hubs (like the Turning Point Hustler alum that I have, ran it once...bought it just see how it compared to SS as they said it was a hot dog alum that competed with SS performance) consists of a brass insert that has the spline then 4 radial brass fingers that run the length of the hub that are molded into a square plastic insert. This fits into the prop rather than the rubber hub.

It doesn't take a rocket scientist to see that on a larger engine striking a solid object this sucker is going to shear. The brass fingers will rip through the plastic and probably fold back in the process. This means that the hub is stripped, and unlike the rubber "slip" hub, can't reset after the strike. You are dead in the water.

I have read on here that they came about to reduce retailer inventories and that on some of the larger engines (100's of hp) the exhaust was so hot it melted the rubber....okaye!

Since I went from alum to ss on a 125 Johnson back in '73, getting tired of props being in the shop all the time, I have had a SS on my rig, other than that one test run. Never a problem.

To each his own.

Mark

 

[Alumarine]

Re: Aluminum vs SS props?????

Like some others I've heard that SS props are harder on the LU if you hit rocks with them.
Over the years my boat has gone through 2 skegs and damaged 30 Aluminum props without any damage to the LU.

I'd be interested in hearing from someone who has hit a number of rocks with a SS prop on.
Just curious.

 

[jimmbo]

Re: Aluminum vs SS props?????

I put my unit on the rocks doing about 23mph with the SS on. Results were bent and torn blades, Small twist to the skeg, no missing chunks, and one bent prop shaft. I was back on the water in two days. dealer didn't have the shaft in inventory so he gutted a new outdrive in the showroom.