E-Tec 50 prop repacement questions

[DaveJ50]

I took a little chunk out of my prop last weekend so I thought I would just run to Iboats and purchase a new stainless prop in about 5 minutes. Keep in mind that I have no idea what I am doing.

My E-tec 50 came with a 13.25 X 17 aluminum prop with 763463 stamped on it which I assume is the part number.

So..I look at all the props on Iboats listed for my outboard and kind of decide on:

Titan Stainless Steel Propeller for Johnson, Evinrude 50 HP(E-TEC Thru Hub Exaust & 13 Tooth Spline)
SKU: 2441-133-17 13.25 X 17
High Rake Blade (Better Acceleration and Notable Bow Lift.) Extra Cupping (Better Handling) High Camber Blade (Fuel Efficient, And More Power)

Then on one of the aluminum prop descriptions I see:

- If currently using uncupped propeller, use cupped propeller having 2 less pitch. Boats with power trim use same pitch.

So now I am confused. I don’t know if my prop is cupped. Do I really need a 13.25 X 15? And what does the power trim (I do) have to do with the pitch needed?

I really don’t need the boat to run better, just not worse.

Thanks

 

[walleyehed]

Re: E-Tec 50 prop repacement questions

Your prop is cupped....
What RPM were you maxing out at with the aluminum prop, and what kind of boat are we talking about?
Power trim allows a higher trim setting while running at top-end to get a few more RPM...and still be able to trim down for rough water or blast-off.

 

[DaveJ50]

Re: E-Tec 50 prop repacement questions

Thanks Kenny

The boat is a 17ft aluminum Lowe 170SE(A basic rivited bass boat). It is no longer produced but a good cross for the places I fish. The specifications for the boat claim that the hull weight was about 650 lbs.

I don't have a tach so I don't know the high RPM but I am pretty happy with my current performance. My GPS claims 32-35 mph and I don't think it could get up on top of the water much faster than it does now. I'm getting 8.7 mpg.

 

[walleyehed]

Re: E-Tec 50 prop repacement questions

Well, I may have to refigure this, but I show about 6200+ a couple with a 17P at 14% slip, 33mph with the 2.67:1 ratio. That being said, a Stiletto in a 17 might well be a good choice.

 

[DaveJ50]

Re: E-Tec 50 prop repacement questions

I don't feel so bad now about not knowing how to choose but I did understand the "Stiletto in a 17 might well be a good choice".

Thanks

 

[walleyehed]

Re: E-Tec 50 prop repacement questions

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