25hp Seahorse wont Plane 2 people UPDATED 7/19/2010

[dyeguy1212]

Ehhhh... take it off?

Obviously :lol:

Thats what I thought.. I guess it wasnt that obvious. :?

 

[Troutman3000]

I wish there was a sarcasm font. I am well
aware that removing the planner board is the beat way to see if it was increasing drag. I was
merely looking for an opinion without having to drive 1 hour to the lake.

 

[Troutman3000]

Lake Report - took the planner boards off and was able to plane out and get about 16-17 mph with me and the wife in the boat.

However, she had to sit on the front to get it to finally plane out. Against the wind we were barley getting 10-12mph.

It was just really hard to plane and it didn't sound like the motor was wot when we were planed out. So I guess the next step is a tiny tac to see where my rpms are. Once that is established I can figure out what prop I need. My old rude's prop was angled more and not so much up and down. Would I need a bigger or smaller prop to plane and go faster?

 

[Troutman3000]

Just took my prop off and its a 9 prop. Whatever that means.

 

[Troutman3000]

Just took my prop off and its a 9 prop. Whatever that means.

So I guess mine is the 9x9 standard prop.

The other options are

PROPELLER, 9 X 10

PROPELLER, 9 - 1/4 x 7

PROPELLER, 9-1/4x11 (Std.)

PROP,AL 9X9 PIN DR (since I have a pin drive is this the only one I can use? I am confused because this parts diagram shows all thses as options.)

https://shop2.evinrude.com/Index.aspx?s1=b61e20a9db5236ea99f459d33a1004f8&catalog_id=0&siteid=1



https://www.crowleymarine.com/johnson-evinrude/parts/30595.cfm

 

[Zum]

Man, figured with a 9 pitch you'd get on plane.
It's not plowing but the bow is in the air?Must be if she had to sit up front.
You say you tried the outboard with it close to the transom?

Normally to get your rpm's up and on plane you would have to lower the pitch.
Each number(9 to 8)should change the rpms around 200...

I'll add this though...I have a 13P and an 11P prop,by myself with the 13 rpms 4800,11-5700rpm so that 200 for each pitch change didn't work for me,wish I had a 12P.

 

[bassboy1]

Can you get any other numbers off your prop? I'm with Zum on the thought that with a 9 pitch you wouldn't have this trouble (you'd have the opposite problem - run out of revs before you ran out of power - that problem, however, wouldn't register much difference performance, based on load). I'm wondering if the number you found was the diameter, and you actually have a higher pitch.

 

[Troutman3000]

Can you get any other numbers off your prop? I'm with Zum on the thought that with a 9 pitch you wouldn't have this trouble (you'd have the opposite problem - run out of revs before you ran out of power - that problem, however, wouldn't register much difference performance, based on load). I'm wondering if the number you found was the diameter, and you actually have a higher pitch.

Yeah guys we are plowing through with the bow in the air, and once she sits right on the front we plane out and get moving if on flat water.

I guess that the motor just isnt the same as the old rude. I will take a picture of the two props for reference. Where else would I look for the prop number? By just looking at the two props I can see that the rude is bigger and the blades are angled more, weight didnt seeem to affect the ablitlty to plane as much as it just affected the top end.

Dawson - what prop is on your old rude? Do you have any extra props I could try out?



Jason

 

[Troutman3000]

When I put the outboard close to the transom it reduced the top end by 2-3 mph, the best spot was in the third set of holes, however that does move the motor away from the transom a bit.

 

[bassboy1]

All my 40's turn a 10 3/8 prop. And, out of them, the only undamaged one left is a 13.5 or 14 pitch, as my rig is probably 1/3 lighter than yours, with 15 more horsepower. Were they the same size, I would have shipped you one to try long ago.

 

[Troutman3000]

All my 40's turn a 10 3/8 prop. And, out of them, the only undamaged one left is a 13.5 or 14 pitch, as my rig is probably 1/3 lighter than yours, with 15 more horsepower. Were they the same size, I would have shipped you one to try long ago.

Thanks Man - you wanna trade :lol:

I guess that this motor is not equipped to push this boat like I want it to. Do you have a tiny tac? I would like to get you in the boat with me so we can figure this thing out and see whether repropping it will help or if it is a lost cause. If the boat is too heavy and the engine is too small there are only a few options. Go slow and not plane out or get a new motor.

Also the motor while it runs well at wot has developed a small skip - hiccup at lower idling speeds. I am going to get the guy down the street to look at it and hopefully it wont cost too much.

Man I miss my rude

 

[Anthony Sisk]

To ask a dumb ? Where does your partner sit when moving?Ive got a 16 ft starcraft runabout that i cut the front out and modified.This is a big boat and all i have is a 15 hp johnson on And it planes out just fine.But when i first put the seat in front where my wife sits when moving it would not plane.So i moved it back about a foot and she does just fine now.

 

[Troutman3000]

To ask a dumb ? Where does your partner sit when moving?Ive got a 16 ft starcraft runabout that i cut the front out and modified.This is a big boat and all i have is a 15 hp johnson on And it planes out just fine.But when i first put the seat in front where my wife sits when moving it would not plane.So i moved it back about a foot and she does just fine now.

I have a seat in the back for me, the battery, and the fuel tank. She usually rides about 4 feet ahead of me where the seat pedastels mounts are located. Middle of the boat really. When she rides in the back we wont plane out.

 

[Zum]

Still say if the outboard is working properly,it would have plenty of power for that boat.
To me plowing through and bow in the air aren't the same thing.
I know what your saying but plowing(to me)means the bows down and your plowing(pushing)through the water and when the bows up,,I'd normally think of putting the motor closer to the transom to get it down.
Maybe try some weight movement...try alittle more up front to get the bow to come down.

 

[Troutman3000]

Still say if the outboard is working properly,it would have plenty of power for that boat.
To me plowing through and bow in the air aren't the same thing.
I know what your saying but plowing(to me)means the bows down and your plowing(pushing)through the water and when the bows up,,I'd normally think of putting the motor closer to the transom to get it down.
Maybe try some weight movement...try alittle more up front to get the bow to come down.

With my buddy and the bait tank we plow through the water. We never really got to a point where the bow is up. I just dont understand the drastic difference between the two motors.

When my wife sat in the middle we couldnt plane, but when she moved up front we could.

Do you think that the motor is a little too long because when I put in it into the last tilt setting, closet to the transom, we actually lose top speed.

 

[bassboy1]

I just had a thought. I, for whatever reason, was always under the impression that your old 'Rude was an '81 model. Not sure why that was stuck in my head, but it was. Hence why I also thought the props would interchange.

But, now that I see the picture, and notice it is a through hub exhaust, I see that the 'Rude is an '85 or later, as up until '84, the pin drive props, and old style gearcases were still used. Also remember, around '85 was when the hp rating changed, so the 'Rude should, theoretically, have 10% more horsepower.

So provided your motor is running well, and doesn't still have an issue that hasn't yet been resolved, it probably lacks 10% of the horsepower over the 'Rude, and as such, turns a smaller prop (glancing at the numbers, it appears the later ones turned a 10 or 11 inch diameter prop).

 

[Troutman3000]

I just had a thought. I, for whatever reason, was always under the impression that your old 'Rude was an '81 model. Not sure why that was stuck in my head, but it was. Hence why I also thought the props would interchange.

But, now that I see the picture, and notice it is a through hub exhaust, I see that the 'Rude is an '85 or later, as up until '84, the pin drive props, and old style gearcases were still used. Also remember, around '85 was when the hp rating changed, so the 'Rude should, theoretically, have 10% more horsepower.

So provided your motor is running well, and doesn't still have an issue that hasn't yet been resolved, it probably lacks 10% of the horsepower over the 'Rude, and as such, turns a smaller prop (glancing at the numbers, it appears the later ones turned a 10 or 11 inch diameter prop).

So what you are saying is that the rude could be 10% more powerful? Even if thats the case I have noticed way more than a 10% loss in power.

Correct me if I am wrong, but you are also implying that given the smaller diameter of the prop on the Johnson I could experience more than a 10% decrease in total speed?