Help with Prop for our new pontoon

MasterMustang

Recruit
Joined
Sep 3, 2018
Messages
1
Hello.

Hello everyone. First time posting :)

We recently purchased a new pontoon boat and used it for the fist time this past weekend. The initial "break-in" period for this Evinrude engine is at least 2 hours of use above 1500RPM. We easily surpassed that this weekend.
A couple things we have questions about:
-the top speed is only about 16mph and at WOT is sitting at 6500 RPM, does this sound right?
-the engine sounds like it's working too hard
-is this the best prop or should we be using something else?

The prop on it from the dealer is a 13-7/8x11 Evinrude Hydrus.

Below is the information about the boat and our use etc...

1. 2018 18', aluminum pontoon
2. Weight - 1500lbs
3. Engine - 2018 Evinrude E-Tec 50HP
3. Average about 4 people on the boat and about 100lbs includes gas and gear
4. Boat will be used for cruising and the odd small tube pulling
5. 25", 2 tunes

Thanks!
 

WesNewell

Chief Petty Officer
Joined
Jan 3, 2018
Messages
497
If the info I found is correct, that's a 2.9 gear ratio engine. With such a high GR, that 11P prop is letting you go way over the 6000 rpm max at wot. You would probably want at least a 13P prop. That should bring your max rpm down close to the 6000 rpm.
 

Scott Danforth

Grumpy Vintage Moderator still playing with boats
Staff member
Joined
Jul 23, 2011
Messages
47,297
welcome aboard

keep in mind when you load people on the 'toon, it will slow down. no need to peg the throttle for a light load only

make sure to get the motor height right prior to dialing in the prop.
 

ahicks

Captain
Joined
Sep 16, 2013
Messages
3,957
It sounds to me like the dealer put the wrong prop on it. If it's turning 6500, even when lightly loaded, it IS working too hard! I would talk with them about your max rpm being way over max suggested.

I think they owe you a prop that will let the engine run at or near suggested. At the very least, they should offer you a terrific deal on the next size bigger (13") prop.

My bet is the tech that rigged your boat is used to rigging boats a little bigger/heavier where that 11" prop would have been fine.
 
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