18' Pontoon 40HP Evinrude replacement prop questions.

monoshock

Petty Officer 1st Class
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Jun 20, 2005
Messages
348
Hello, I’m looking for some help on a replacement propeller for my pontoon 18 ft tracker Bass Buggy with a 40HP Evinrude. The aluminum one on it now is fine, it’s a 12 ½ x 13. I want to have an extra so thought I might as well get a SS one and have the old one for the extra. I found a close out deal on iBaots for a Michigan Wheel Rapture 11 ¾ x 15. Would this be a good replacement? I’m thinking a smaller diameter with a steeper pitch it should be okay, but want some input from someone with more experience. Thanks<br /><br />Here's the link for the new prop.<br /><br /> http://www.boat-props.com/propeller...vinrude/rotation-Standard/chart-14/index.html
 

monoshock

Petty Officer 1st Class
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Jun 20, 2005
Messages
348
Re: 18' Pontoon 40HP Evinrude replacement prop questions.

Help
 

Silvertip

Supreme Mariner
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Sep 22, 2003
Messages
28,758
Re: 18' Pontoon 40HP Evinrude replacement prop questions.

The small change in diameter has little effect on the performance of the prop. Pitch changes have the most effect. The 15 pitch will very likely cause lugging of the engine. The 13 pitch is probably at the limit for your 'toon. 15 pitch on a 40 is the "standard" prop for a "V" hull and in some cases even that is marginal. I'd stick with a 13 and your engine will live longer.
 

monoshock

Petty Officer 1st Class
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Jun 20, 2005
Messages
348
Re: 18' Pontoon 40HP Evinrude replacement prop questions.

Thanks,Upinsmoke.
 

Silvertip

Supreme Mariner
Joined
Sep 22, 2003
Messages
28,758
Re: 18' Pontoon 40HP Evinrude replacement prop questions.

It should work just fine. If its a ventilated prop as the info indicates, it will help with getting started. Vent holes allow the engine to rev a bit during takeoff. The holes are not a factor at higher speeds. They can be plugged if it turns out they create a problem. I may pop for one of these myself. Thanks for the link.
 

monoshock

Petty Officer 1st Class
Joined
Jun 20, 2005
Messages
348
Re: 18' Pontoon 40HP Evinrude replacement prop questions.

Thanks for your help. I just ordered one,about $82 with shipping, I,ll let you know how it works out.
 

monoshock

Petty Officer 1st Class
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Jun 20, 2005
Messages
348
Re: 18' Pontoon 40HP Evinrude replacement prop questions.

Hello, I received the new Rapture - 11-3/4 x 13 - 3 blades SS prop on Friday and took it for the first run on Sunday. I was very disappointed; As soon as I throttled up I could tell this wasn’t going as planed. The new prop dropped my top speed about 5mph, and it took longer to get to top speed. I reinstalled the old prop. Does anyone have a suggestion, the new prop is the same pitch, just ¾ smaller?
 

walleyehed

Admiral
Joined
Jun 29, 2003
Messages
6,767
Re: 18' Pontoon 40HP Evinrude replacement prop questions.

The SS prop is a much more efficient design for starters.<br />The speed drop is not good but most importantly, what is the RPM at with new?? with old??
 

monoshock

Petty Officer 1st Class
Joined
Jun 20, 2005
Messages
348
Re: 18' Pontoon 40HP Evinrude replacement prop questions.

I don't have a tach. It's for sure reving higher, I could tell by ear.
 
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