Pontoon specific props

[lmuss53]

I'm pretty familiar with pontoon boats and motors and how to properly prop your boat. I have seen many responses in forums about pontoon specific props, like 'elephant ears" or cupped props. Does anyone actually make and sell props specifically for pontoons or do you have to have the props tweaked by a prop shop to get the right cup, blade size, etc?

 

[Silvertip]

Re: Pontoon specific props

Mercury has an excellent 14 inch prop for the Big Foot series of motors. Large rounded blades (hence the term elephant ear) and four of them so this prop provides great push both forward and reverse. A standard prop has nowhere near the thrust in reverse than a pontoon prop has.

 

[GaryO]

Re: Pontoon specific props

Okay, now I have a question. If a person would switch from their present 3 blade prop to a 4 blade, would you keep the same pitch or make a change on that also. I have a 1991 Evinrude Intruder 150 on a 22ft. 1991 Misty Harbor and I run at 2500 to 3000 rpm which gives me a medium cruising speed that everyone on board enjoys. With the 4 blade can I cut my rpm down to save fuel without the pitch change?

 

[Silvertip]

Re: Pontoon specific props

You are jumping on someone elses thread. In the future please start your own. But since you are here, you are chaning props for the wrong reason. The best prop is one that allows the engine to rev at or very near the top of the manufacturers wide open throttle rpm band. On your engine that is probably 5500 - 5800. So what you need to do is load the boat with what you consider is your average load. Then run wide open. Note the WOT RPM. If the prop is correct the engine will run in the recommended band. If not, you need to increase or decrease pitch. As for three vs four blade, you can only make a comparison if the props come from the same manufacturer and even then there is no exact number but generally a four blade will lower rpm a bit. It all depends on design. I know you want to run at slower RPM but if the engine is lugging at WOT it is lugging at any other rpm as well. More throttle opening burns more fuel. So we can't answer your question as you provided no current performance info.

 

[GaryO]

Re: Pontoon specific props

Sorry, was just wondering.