DON'T NEED SS PROP ON 4 STROKE

[g-man]

I BOUHGT A 04 1800 FISHERMAN WITH 04 140H.P. JOHNSON 4STROKE.THE DEALER TOLD ME I DIDN'T NEED A STAINLESS PROP ON A 4STROKE BECAUSE THERE ISN'T THE TORQUE LIKE A 2STROKE THAT WILL FLEX THE PROP.THE ALUMINUM PROP HE PUT ON HAS 3X14X19 STAMPED ON IT.WITH 2 PEOPLE,20GALLONS OF GAS,3 BATTERY'S AND LIVEWELLS EMPTY I GET 42 MPH.ON THE GPS AT 6100 RPM.I DON'T KNOW ENOUGH ABOUT PROP'S TO KNOW IF HE IS CORRECT OR IF I AM GETTING THE PERFORMANCE I SHOULD WITH THE SET-UP I HAVE.ALSO THE MOTOR IS MOUNTED IN THE SECOND HOLE FROM THE TOP.THANK'S FOR ANY INPUT.

[Pitts]

Depends on what you are trying to accomplish with a stainless prop.
I your a first time newbie boater and have never run stainless and don't care about the absolute best top speed and handling you can have and are satisfied with the aluminum then you don't need a stainless.

But if you want maybe great handeling and throttle response, the extra 5 mph, and the bow lift to get the splash line behind you and lessen your spray blowback in you face syndrom from most aluminum boats then finding the optimum SS prop is probably for you.

If you are new start slow and read and learn the different steps to increase performance with a SS prop. Do your homework then find a dealer or supplier that with a deposit and a clean no damage return will let you try out several different props and will help you set up your boat with the help of a motor lift at short notice for a nominal fee.

If this is you first larger boat take it easy and learn how it handles and what can be done with it and what cannot be done with your particular boat the after careful consideration and new learning curve you have decide whether you would like to try to go stainless and improve your performance or if the aluminum is good enough.

Good luck
Pitts

[work2fish]

Well, I've got the 20" Suzuki stainless on my DF140/1700 Fisherman combo. The stainless prop does indeed improve the handling and speed as I ran it for a while with a 19" aluminum beforehand. So, from personal experience only, I can tell you it does make a difference.

Good luck,

[REW]

The statement about the difference in torque - between a two stroke and 4 stroke is completely in error.
Hp is hp is hp is hp.
It doesn't make any difference if the power is generated by a 2-stroke engine or a 4-stroke engine. If a 140 hp 2-stroke engine has enough torque to twist a prop , the exact same thing will be true for a 4-stroke.

----
The other post about what you want out of a boat is right on.
If you are happy with what you have - enjoy. If you want a bit more - and a bit more durability, go to the stainless.

From reasing your post, you are overrevving your motor just a bit. You shouldn't be running over 6K.

Many folks are running this rig, and the prop of choice seems to be the 14X20 pitch Suzuki stainless.

Talk to your dealer and see if you can do a try before buying. i.e. take the prop home, give it a test run - then and only then - buy the prop. If you aren't happy - take it back. Many dealers work with their customers in this way to make them happy.

Take care
REW

[tom d]

Most folks I talked to before I bought my SS said that a the break point on SS purchase is about 100 hp. They said above 100 hp there is enough bend in aluminum to notice a difference in the performance of a SS version.

Having said that, let me add one thing to the equation. If you fish waters with lots of rocks and underwater obstacles you might want to stay with the aluminum. If you hit something with the prop, the prop ears will bend and absorb much of the punishment. Hit the same object with SS and the ears transmit the punishment to your gearcase. IF it is just wood, you will be fine with the SS, as was a buddy of mine who found a chunk of wood on his SS prop blade as he inspected it to find out why his engine would not perform well on LOW.

Just to make your decision even harder, if you hit the object with the skeg or the lower unit itself you can still take out the lower unit by breaking the seal during the collision and having the motor subsequently push out all the lube. It gets replaced with surrounding water and will weld your gears for you. Been there, done that. Even an aluminum prop won't protect you then. Mine didn't.

I DO have a SS on my 150 hp motor. I kept the aluminum as a backup and for use when I fish waters with a lot of rocks in them. Having a backup is a GOOD thing. Been THERE, too!

[Huskie]

I think I understand your delers statement about torque. Yes it is true that torque and horsepower are related by a simple mathematical equation and two motors producing the same hp will produce identical torque when run at that hp.
What your dealer was probably trying to say was that 2 strokes (same displacement for both engines) produce more power per revolution of the crank since they have 2 power cuycles for every single power cycle of a 4 stroke. What this means is , two similar displacement motors, one 2 stroke and one 4 stroke can produce the same hp on the top end but the 2 stroke will usually have more power than the 4 stroke throughout most of its rpm range. this can also be expressed as the 2 stroke has a broader or "fatter" power curve than the 4 stroke.
AS far as the blade flex issue, both engines have the ability to flex the aluminum props blades once the power in each is sufficient. This is especially true at WOT.

The difference between a good stainless and aluminum prop is more than ridding of the flex factor. Good, reputable brand SS props are given a lot of research and development time in order to maximize their performance. Typically, aluminum props lack this quantity of effort and time to develop them to the same degree, since SS props are there for that purpose (and the flex issue is dealt with too).

Get used to your boat with the aluminum prop first, then try different stainless props. You will then feel the difference between the two types of props. Some individuals are perfectly happy with aluminum props (and knowing that repair is much cheaper then SS). It all depends what you want from your rig, and how much $$ you are willing to spend getting there.

[T-Mac]

The IPS hull reacts really well with a stainless prop. The bow gets lifted and the spray comes off quite a bit further back, when a decent stainless prop is present.

Not talking hole shot... talking handling and ride.

4 stroke-or-2 stroke...makes no difference.