1996 Evinrude 50hp Prop Pitch Question

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spudz72
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1996 Evinrude 50hp Prop Pitch Question

Post by spudz72 »

As I've mentioned before I picked up a 96' 26X recently and it has a 1996 Evinrude 50hp outboard on it but the aluminum prop has some dings in it and I want to put on a new prop because of this. The prop that is on the motor now shows as 13 x 19. Does anyone have any idea if this is the proper recommended pitch prop for a 26X? Figured you guys would be the ones to ask before I went and bought another 13 x 19.
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DaveB
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Re: 1996 Evinrude 50hp Prop Pitch Question

Post by DaveB »

I don't know about the Evinrude but I have a 50 hp Honda 1997 4 cycle and have tried the original 11.25 diamiter x 13 pitch , 3 blade and found it to cavitate at high rpms. I than put on a 11.8 x 9 Solas 4 blade and this was a perfect fit for high speeds 5800-5900 rpms @ 15.8 knots with a fully loaded boat for a weeks cruise and 425 lbs 2 persons aboard.
Problem is cruiseing at 6-6.5 knots in calm water I did 2600-2800 rpms and since I am more interested in the 6 knot cruiseing felt the 2600 rpm's was to much.
I just ordered a Solas Altima 3 blade with 11.35 diamiter and 12 pitch. this will bring my rpm's down to around 2200 rpms and cruise at 6-6.5 knots and thats what I want, I will probably do only 12-13 knots but all I need to do is 8 7 knots to empty ballest.
Your 13 diamiter and 19 pitch is way over the limit and your rpm's probably tops out around 3500-4000 rpms.
If you stay with a 13 inch Diamater I would think a 10-11 pitch prop. will do fine.
Keep in mind that useing a 4 blade prop. usually requires going down one pitch compared to a 3 blade .
Dave
spudz72
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Re: 1996 Evinrude 50hp Prop Pitch Question

Post by spudz72 »

Thanks for the comments. I called my local evinrude dealer and he seemed to think the 19 pitch seemed really high as well. More like 11-13 is what he thought would be about right for the boat with that engine. He compared it to a 24ft pontoon boat having a 50hp evinrude on it and it would have a 11-13 pitch likely. Surely there must be someone on this forum with an Evinrude or Johnson 50hp 2 stroke from the mid to late 90's? If so let me know what pitch your prop is. Thanks.
spudz72
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Re: 1996 Evinrude 50hp Prop Pitch Question

Post by spudz72 »

Just a follow up to this.

I called Macgregor head office just now and asked what they thought about the prop pitch question and he seemed to think a 13x11 would be more appropriate for this engine on the 26X. So the more people I talk to it seems they agree the pitch on this prop now is way to high...
Kelly Hanson East
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Re: 1996 Evinrude 50hp Prop Pitch Question

Post by Kelly Hanson East »

19 is way overpitched - so far that this is an easy call.

I have a 14x11 on my :macx: but a different engine and transmission (Merc 50 HP BF) so you need to get advice from a 'Rude Engined Person

patience...
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Re: 1996 Evinrude 50hp Prop Pitch Question

Post by SailDog »

Kelly Hanson East wrote:19 is way overpitched - so far that this is an easy call.

I have a 14x11 on my :macx: but a different engine and transmission (Merc 50 HP BF) so you need to get advice from a 'Rude Engined Person

patience...
I've got the same boat and engine, what kind of top end speed do you get with the 14x11?
Kelly Hanson East
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Re: 1996 Evinrude 50hp Prop Pitch Question

Post by Kelly Hanson East »

About 16 mph with a fairly heavy load. I cant reach WOT specs with this prop when loaded

I cruise 6-8 mph 99% of time under motor
SailDog
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Re: 1996 Evinrude 50hp Prop Pitch Question

Post by SailDog »

Kelly Hanson East wrote:About 16 mph with a fairly heavy load. I cant reach WOT specs with this prop when loaded

I cruise 6-8 mph 99% of time under motor
Humm, interesting, ours came with a 14x10, and I had no problem touching 6000rpm, Had to throttle back to keep it under. Wonder if our tach is off... It was our first time out so we kept it ballasted, and were seeing mostly 11mph at about 5600 on the GPS with 3 onboard.
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Re: 1996 Evinrude 50hp Prop Pitch Question

Post by Kelly Hanson East »

I had a 14x10 previously and reached 5600rpm fine. That is the 'correct prop' for a :macx:
spudz72
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Re: 1996 Evinrude 50hp Prop Pitch Question

Post by spudz72 »

I called Evinrude directly today and they told me that my motor at WOT should be 6000rpm, or close to it.

I'm putting the boat in the water today so will see what this 13x9 does at WOT and go from there.

Thanks for all the comments thus far...
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Re: 1996 Evinrude 50hp Prop Pitch Question

Post by spudz72 »

Well I didn't get the boat in the water until today and as I suspect based on comments the prop is definitely too high of pitch. With WOT the engine was only revving just a tad over 3000rpm and got me about 13mph. Based on the 6000rpm WOT spec that evenrude told me it should rev at it's prop shopping time for me. It's a 3 blade prop on there now. I see you can get 4 blades as well but unsure of what the advantage is if any. I'm thinking a 13x11 would be a good one to try first.
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DaveB
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Re: 1996 Evinrude 50hp Prop Pitch Question

Post by DaveB »

This is a update from my previous post. I spent last 3 days trying out the new Solas 3 blade 11.35 x 12 prop. and the following is results on a fully loaded boat with 400 lbs persons, 3 batteries and all gear on a Mac. X 1997 with 50 HP Honda.
2000 rpms @5 knots even, 2400 rpms @6.1 knots, 2800 rpms @ 6.6 knots. Top RPMS were 5100 @15.3 knots.
This is what I was looking for as I cruise at 6 knots under power and tho the prop. couldn't reach the Manifactures RPM's between 5500-6000 I can live with it. Seas were 1 ft. or less.
On your larger Diamiter prop I would go with a 13 X11 for low end cruise RPM's and a 13 X10 for reaching your RPM's for slightly higher speed .
Dave



spudz72 wrote:Well I didn't get the boat in the water until today and as I suspect based on comments the prop is definitely too high of pitch. With WOT the engine was only revving just a tad over 3000rpm and got me about 13mph. Based on the 6000rpm WOT spec that evenrude told me it should rev at it's prop shopping time for me. It's a 3 blade prop on there now. I see you can get 4 blades as well but unsure of what the advantage is if any. I'm thinking a 13x11 would be a good one to try first.
spudz72
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Re: 1996 Evinrude 50hp Prop Pitch Question

Post by spudz72 »

Just wanted to update where I was at with my prop situation, which I'm still having problems with. Well I got my local dealer to get me a 13x11 prop, and when I got it home and went to put it on I noticed that it was the wrong shaft size, it was too small, like it was for a smaller motor like a 10hp or something. So I took it back and this time took my original 13x19 prop that I was only hitting 3000rpm WOT with, and showed them. Somehow the book showed the prop they sold me would fit but it was obviously wrong. So upon further investigation I was told there was not a 13x11 available that would fit my motor. However they could get me a 14x11. So I said to go ahead and order it for me. I put the 14x11 on and it fit but the 3 blades came really close to the hitting within 1mm, but did not hit.

I forgot to take out my GPS with me but at WOT I can now get about 4000rpms with 3 people onboard, no ballast, mast removed, and some supplies (about 200lbs). So I'm still a ways off from the 6000rpm WOT that evinrude recommends.

My question is would a 14x11 make my outboard rev lower then an 13x11 if it were available? I'm thinking maybe I should try a 13x12 instead since it's probably available for my motor?

Also just to be sure I had a compression test done on my motor and all 3 cylinders read around 120 so it is up to spec in the regards I think.

Comments would be appreciated.
Frank C

Re: 1996 Evinrude 50hp Prop Pitch Question

Post by Frank C »

Hmmm ... 3 persons on a traditional, 2-stroke Evinrude 50, and still only 4000 rpms??
I'd guess you really needed a 14x10. If they don't make one, you can have the 14x11 slightly de-pitched.
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Zoran
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Re: 1996 Evinrude 50hp Prop Pitch Question

Post by Zoran »

I had 12x9 three blade on my new tohatsy 50 tldi, and I reached only 5000 rpm three peple on board, medium load no ballast. Today I got 4 blade 11x7 from my dealer and I will try it tomorrow. Apparently that is the next lower pitch available from Nissan

Zoran
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