SS vs. Sacrificial Aluminum Prop Concept

[Spoiledrotten]

I know this is a subject that has been most likely, discussed to the limits, but I just heard a concept that got me thinking and wondering what your take was on it.

I've always gravitated toward a SS prop, but when talking with a neighbor of mine this weekend, he told me that he stays with the aluminum for one reason; when you hit something with an aluminum prop, you'll most likely crack, break, or even completely sheer the aluminum blades off of your motor. When you hit the same thing with your SS prop, with will either chew up the foreign object or break something within the lower unit or elsewhere in the motor. We talked about the prop being the sacrificial lamb much like the anode fin on the motor. It surely makes sense to me to have a $150 damaged prop rather than a $$$ repair bill on the inside of my motor.

What say ye?

[Bamaman]

We live on a large rock bottom lake. When I had inboard outboard boats, I'd go through an aluminum prop yearly. Luckily my cousin owns a prop shop and would fix'em cheap.

When I switched over to a stainless prop, I went 12 years with scarcely a scratch on the propeller.

That's my experience with stainless props. I still believe that every boat with over 115 hp needs a stainless prop for maximum efficiency and durability.

[robster]

In the non-freeze months we use our SS prop and keep the motor raised out of the water, during the freeze months I switch back to our aluminum prop and keep the motor trimmed all the way down into the water. I also keep a Magnesium grouper (anode ),Magnesium is for fresh water in the water at the stern year round. http://www.amazon.com/Martyr-Magnesium- ... +magnesium. The alligator clip on the grouper anode clips to the engine mount bolt. The SS prop performs better than the aluminum for water sports, is what we found. Our boat lives in a fresh water slip year round.

Cheers,
Robert

[Spoiledrotten]

So from what I'm getting from the only two posts so far is that having a SS prop with a possibility of it hitting something under the surface and ripping up the equipment inside the lower unit is not an issue with you?
I've heard from people that love the SS that it will just chew up anything it hits, but for those things lingering that it can't chew up, something has to give.

I'm certainly not arguing anyone's point. I'm just trying to get off of the middle of the fence. I like both sides of the coin for now. I just wanted to see what the opinion was about messing up my motor if I hit something that the SS can't conquer. Thanks for the post so far.

[RcgTexas]

Right now I am running an aluminum prop on my 135 Honda. it may not be providing exceptional effiency but its a pontoon boat. I will do 32 mph with the aluminum and probably 34 with the proper SS.

I just had the prop shaft straightened because the dealer sold me the used motor with a new powerhead with a bent shaft. I went to aluminum to get the pitch right before I had the SS cut and pitched down. I think the sacrificial aspect of the aluminum wheel is a good idea since the cost difference is tremendous. This is my

[Littlehoe]

I have tried all kinds of props and so far the best I found was a 4 blade aluminum. The 3 blade stainless gave me a little more top end but I found I had cavitation/prop blowout more often with the stainless. If I recall though most of the new stainless props and these aluminum ones have a rubber/plastic hub system that is supposed to break before the internals of the leg if you hit something.

[rancherlee]

If you hit something hard enough to bend the prop shaft with a stainless prop usually there is damage to the skeg and the lower unit will need to come off anyhow. The new hub kits are also designed to shear loose a lot more easy than a pressed in rubber hub. If I'm on a new lake I generally toss a 4 blade aluminum on to do my "exploring", switch to the stainless If I know the lake.

[moregooder]

I have a full top on a 24 foot boat and the 115 will push it along at 28 with only me on it. so I cant see the value in a high dollar ss prop because the boat is far from high performance. having had a prop fixed every fall I can see the value of a sacrificial pop to save the bottom end but that meant keeping a spar prop to use as one was being fixed, still tying up 300 bucks. I finely went to a fiber composite Perona prop. having had it for 2 years now I find myself vary pleased with it the hub has a life time on it and if I do bang a blade it costs only $25 and 5 mins to knock the bad blade off and put the new one on

[BobG]

I've bought a lot of aluminum props...at $150 or so each.
I've bought ONE SS prop - sure, it was $350 or so, but it's on the second season at about 200 hours per season.

Mercury hub inserts are designed to break, instead of the lower unit innards.
During the several times I've cratered an aluminum prop, the hub components never broke. The prop is weaker than the hubs.

[RcgTexas]

I totally understand about the hubs supposed to slip before the prop breaks on a SS prop.

I had a twin engine offshore fishing boat in Hawaii once that hit a coral head with the port engine. The Drive shaft broke on a Johnson salt water engine. NO SLIP ! I am not saying it wont help but it is not 100 % infallible.

I rarely hit anything because I'm careful and watch the depth I'm in. However, if you do hit something a
$150 dollar prop is easily replaced and it most times can be repaired. A SS can ruin your whole season. IMHO

[BobG]

I rarely hit anything because I'm careful and watch the depth I'm in. However, if you do hit something a
$150 dollar prop is easily replaced and it most times can be repaired. A SS can ruin your whole season. IMHO

Same here - and I DO carry an aluminum spare, just in case.

[justfishing]

The real benefit of a ss is performance. My understanding is it wont make a difference on a 90hp.

My question is how often have you struck something with your prop. At what speed. What was the damage. If you are idling through and area then a SS will likely be undamaged and a aluminum will be ruined. At high speed it will be luck of the draw. Your insurance will cover a new lower unit.

[Spoiledrotten]

Very good input, guys. Thanks.

[Spoiledrotten]

The real benefit of a ss is performance. My understanding is it wont make a difference on a 90hp.

My question is how often have you struck something with your prop. At what speed. What was the damage. If you are idling through and area then a SS will likely be undamaged and a aluminum will be ruined. At high speed it will be luck of the draw. Your insurance will cover a new lower unit.

Well, it just happened yesterday! The wife and I were cruising up the river, when bang, we hit something as we went along. The boat started shaking, and I quickly cut the engine. I tilted the motor up to see the aluminum prop destroyed. I puttered over to the nearest sand bar, about 100 yards, and changed out the prop. I had just put the new 4 blade aluminum on it about 3 - 4 weeks ago. I luckily had the original prop with the tools to make the change. When I got the new prop installed, I left the dock only to get some more vibration. I pulled back onto the sand bar and investigated further. Bent shaft! There was no sign that it hit anything but the prop. No scuff marks on the lower unit anywhere. I eased it back to the marina, loaded it on the trailer, and brought it home.

I'm thinking that if that had been a SS prop, it would have done much more than bend a shaft.

[TDJ2591]

I have a full top on a 24 foot boat and the 115 will push it along at 28 with only me on it. so I cant see the value in a high dollar ss prop because the boat is far from high performance. having had a prop fixed every fall I can see the value of a sacrificial pop to save the bottom end but that meant keeping a spar prop to use as one was being fixed, still tying up 300 bucks. I finely went to a fiber composite Perona prop. having had it for 2 years now I find myself vary pleased with it the hub has a life time on it and if I do bang a blade it costs only $25 and 5 mins to knock the bad blade off and put the new one on

My used boat came with a Piranah composite prop. While the speed and power seemed about right, I never could get the RPMs up to 5,000 RPMs or higher. I tried 3 different pitch blades (15, 13 & 11) What was really weird was that the RPMs fell when I dropped from 15 to 13 pitch and the speed increased. The folks at Piranah were very very nice but couldn't explain it.

I just switched to a 15-1/2 x 13 SS and RPMs are finally where they should be. The Piranah with its multiple sets of blades is now the spare. For my boat, the Piranah was definitely the wrong prop.