more thrust from a 1976 evinrude 2602s 2hp?

sushieater

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Oct 28, 2011
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6
I have a 1976 evinrude 2hp that has been sitting in storage most of it's life and is running good.

I wanted to use it to push my hobie cat 18, but at full throttle it barely moves in any counter current. Same results from a dingy. Even in calm water, it's barely moving faster then walking speed.

Stock prop 7 1/4 x 4 1/2
http://www.boats.net/parts/detail/brp/B-0316557.html

Anyone know if you can put a higher pitched prop on this? It doesn't look there any alternative prop options originally that I could find.

thanks
 

ondarvr

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Apr 6, 2005
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11,527
It's probably a short shaft motor (15"), if you have a 20" transom it won't work well.


You would probably want a lower pitch prop with more blade area, but for those motors it's most likely not an option.

That motor shouldn't move either of them very fast, but with no wind or current it should do
Ok.
 
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Sea Rider

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You need to test that OB at wot while lightly loaded with an induction tach to check if within factory stated max wot rpm range, if prop selection is vey short or scarce, if prop is alum, could modify pitch at a prop shop to pull revs higher and push much better than before.

Happy Boating
 

steelespike

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Check out the 2hp jon boat on youtube. Very light load but it actually planes.
Check other 2 hp tests I think you will note much better than your 2 hp at this point.
Check the compression,take the cowl off and note the movement of the throttle components.
Spin the flywheel by hand should turn easily with the plugs out. If it seems stiff the gear case may have a problem.
Fuel mix is 50:1 regardless what your original literature says.
It develops 2 hp at 4500. At 2 hp just about any 2 hp prop will work. Lets face it.
The Dingy should work and disregarding windage the Hobie should move reasonably well.
If your dealing with current and tides could be a problem.
 
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Sea Rider

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A dinghy if being small and inflatable much worst, too much hull drag to overcome fast with just 2 HP, a larger Cat will perform better at displacement speed. A prop maximization if possible along induction tach is the right way to go..

Happy Boating
 

fhhuber

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Jun 19, 2014
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Actually, more pitch is the wrong answer... more blade area and lower pitch.

If you are whipping the water and getting nowhere don't add pitch.
 

steelespike

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A dinghy if being small and inflatable much worst, too much hull drag to overcome fast with just 2 HP, a larger Cat will perform better at displacement speed. A prop maximization if possible along induction tach is the right way to go..

Happy Boating

I didn't mean to imply speed I figure with a healthy 2 hp you throw a couple of folks in the dingy crank the motor up and wait to get there.
In my youth 6 years old I had a 10ft flat bottom sharpy 1.1 hp that I took out in Hurricane Hazel in the 1950s 200 ft into the wind then a mile down wind
in the shelter of an island.
 

ondarvr

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I had a small dingy about 6 or so feet long as a kid, it had a 1.5 hp Johnson on it, same motor as OP but an older version. It would plane that small boat if I had it balance correctly.
 

Sea Rider

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Boating has 2 water "speed" performance behaviors, displacement speed and plane speed, being the latter where all the fun starts.. With 2 HP underpowerd OB will only attain displacement speed wether slow or fast one, will depend entirely on boat lenght, hull drag and total weight. Will surely take you there, be sure to take some cold ones with you to compensate that boring never ending journey at just displacement speed.

A kid is a kid, a adult is a adult , different weights and boating scenarios with same OB.

Happy Boating
 
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