E-Tec 60 Prop for 26M

[rwmiller56]

Hi, everyone. It's been a while since I posted, but I'm still enjoying my 26M!

Sorry if this has been discussed before. I did a search, and didn't find any answer specific to my situation.
I recently repowered my 2005 26M with a 2015 E-Tec 60 HP. I operate the boat on S.F. Bay, so I run full ballast all the time, and the boat is heavily loaded with supplies and people.
The outboard dealer installed a 13.5" x 15" prop. The WOT speed is 14 kts at 5000 RPM. This is about the same speed as my previous motor, a Johnson 50 HP 4-S. I was hoping for more speed.
It seems that I need to use a smaller prop. I can reduce the diameter to 12 1/4" or 11 1/4", while keeping the pitch the same at 15". Or, I could reduce the pitch to 14" and go with an 11 1/2" x 14".
Which size would be the best to put the RPM at 5750?
It would be great if I could get a reply from someone who has a 26M with an E-Tec 60 HP, and who operates the boat heavily loaded.

Thanks,
Roger

[kadet]

I use a 14x11 for getting 5800 rpm heavily loaded this gives about 16knts but burns lots of fuel so I mainly travel at hull speed these days

I have a 13.75x13 with the big ears for pushing along at hull speed, without ballast and lightly loaded this one gave me 19knts once with ballast and a load I cannot get much above 5200 rpm

Don't go to smaller diameter prop you will only induce slip on these barges. Go for a lower pitch to get you optimum rpm the ETEC has a big gear case designed to spin the bigger props.

[rwmiller56]

I use a 14x11 for getting 5800 rpm heavily loaded this gives about 16knts but burns lots of fuel so I mainly travel at hull speed these days

I have a 13.75x13 with the big ears for pushing along at hull speed, without ballast and lightly loaded this one gave me 19knts once with ballast and a load I cannot get much above 5200 rpm

Don't go to smaller diameter prop you will only induce slip on these barges. Go for a lower pitch to get you optimum rpm the ETEC has a big gear case designed to spin the bigger props.

Thanks Kadet! It sounds as though the 14 x 11 prop is the best way for me to go. I'll let you know how it works out.
Roger

[1st Sail]

I run the 13.75 x 13 for general cruising. Full ballast, 2 batteries, 12 gal fuel, 2 adults, lightly loaded the 13.74 wot 5600 rpm, 4 adults and wot 5400 rpm and I can over heat the engine. 14 x 11 wot 6000 rpm which is the rated top end. I would recommend the 14 x 11 with the Etec 60 running a little heavier than mine.

[rwmiller56]

I tried the 14x11 prop today. Full ballast, 1 person, 12 gallons of gas, lots of gear in the boat. 10 kts at 6000 rpm. WOT was higher than 6000 rpm, but I only ran it up to rated maximum of 6000 rpm.
So it seems that the 15" pitch prop is too large, and the 11" is too small.
Next I'll try the 13.75" x 13" prop.

[kadet]

I tried the 14x11 prop today. Full ballast, 1 person, 12 gallons of gas, lots of gear in the boat. 10 kts at 6000 rpm. WOT was higher than 6000 rpm, but I only ran it up to rated maximum of 6000 rpm.
So it seems that the 15" pitch prop is too large, and the 11" is too small.
Next I'll try the 13.75" x 13" prop.

Man that's 53% prop slip You may need a 4 blade with that kind of slip. How much gear is in your boat (weight).

[rwmiller56]

I tried the 14x11 prop today. Full ballast, 1 person, 12 gallons of gas, lots of gear in the boat. 10 kts at 6000 rpm. WOT was higher than 6000 rpm, but I only ran it up to rated maximum of 6000 rpm.
So it seems that the 15" pitch prop is too large, and the 11" is too small.
Next I'll try the 13.75" x 13" prop.

Man that's 53% prop slip You may need a 4 blade with that kind of slip. How much gear is in your boat (weight).

I've got some stuff......
The slip was lower, about 40%, with the 15" prop.

[kadet]

Sorry with that kind of slip I don't think 13 pitch will help

Are your speed measurements speed over ground or speed through water cause that is a lot of slip and I am wondering whether current is playing a factor here?

If too heavy you may be to low in the water to get up on plane properly with a 60hp as there is just too much wetted surface.

:macm:s are fat a$$ boats so slip is unavoidable but should be around 25%.

[rwmiller56]

Sorry with that kind of slip I don't think 13 pitch will help

Are your speed measurements speed over ground or speed through water cause that is a lot of slip and I am wondering whether current is playing a factor here?

If too heavy you may be to low in the water to get up on plane properly with a 60hp as there is just too much wetted surface.

:macm:s are fat a$$ boats so slip is unavoidable but should be around 25%.

It's speed over ground. I use a GPS. The tidal current is only 1-2 kts maximum where I boat. It doesn't make a big difference in the SOG, only 1-2 kts. The speed numbers I posted are an average of both directions.

I think I know the problem. I have non-ablative bottom paint on the boat, which is old and is badly in need of a re-do. It's over 4 years old, and the boat sits in the water all the time. When I had the boat on the trailer for the E-Tec repower, I noticed that the paint is very rough.
All I want for now is to get the WOT RPM near 6000 RPM. If I get 14-15 kts of speed, I'll be happy, until I re-do the bottom paint.

The prop slip calculation on my old Johnson 50 HP, with a 12 x 10 prop, was 35%. That was with fresh bottom paint. That motor is now history. It was damaged by salt air ingress. The boat is in a very harsh environment.
Roger

[EZ]

I think I have the 13.75x13 prop, but it will be some time before I can check as my boat is 30 MI away.

My engine is 50hp and gets up to 5500 rpm with ballast. I don't power wot with ballast very much so can't say what the max speed is. About 5800 rpm and 19 mph with out ballast.

[rwmiller56]

I think I have the 13.75x13 prop, but it will be some time before I can check as my boat is 30 MI away.

My engine is 50hp and gets up to 5500 rpm with ballast. I don't power wot with ballast very much so can't say what the max speed is. About 5800 rpm and 19 mph with out ballast.

EZ,
I think I've seen "Stray Monkey" in the dry storage yard near the boat ramp? I keep my trailer stored there. And I think you had your boat slipped for a while at the marina, at the same dock mine is at? We may have spoken before. A small world it is!
I just repowered "Lazy Lightning" with an E-Tec 60 hp, so it was out of the water for a while.

Roger

[EZ]

I think I have the 13.75x13 prop, but it will be some time before I can check as my boat is 30 MI away.

My engine is 50hp and gets up to 5500 rpm with ballast. I don't power wot with ballast very much so can't say what the max speed is. About 5800 rpm and 19 mph with out ballast.

EZ,
I think I've seen "Stray Monkey" in the dry storage yard near the boat ramp? I keep my trailer stored there. And I think you had your boat slipped for a while at the marina, at the same dock mine is at? We may have spoken before. A small world it is!
I just repowered "Lazy Lightning" with an E-Tec 60 hp, so it was out of the water for a while.

Roger

Yep, that's me! I've had my etec for over 10 yrs and have been very happy with it. Very reliable. I think you'll be happy with it.

If you ever have any questions feel free to pm me.

[rwmiller56]

I finally got it dialed in with the 13.75 x 13 prop. She makes 15 kts at 5900 RPM. Very nice motor. I'm a happy boater

[kadet]

I finally got it dialed in with the 13.75 x 13 prop. She makes 15 kts at 5900 RPM. Very nice motor. I'm a happy boater

That's good news but is opposite to what I expected on a heavily ladened boat given my own experience with prop pitch battles
I am curious was your 14x11 large cupped or standard raked?

[rwmiller56]

I finally got it dialed in with the 13.75 x 13 prop. She makes 15 kts at 5900 RPM. Very nice motor. I'm a happy boater

That's good news but is opposite to what I expected on a heavily ladened boat given my own experience with prop pitch battles
I am curious was your 14x11 large cupped or standard raked?

Beats me. Here is a link to the 14 x 11 prop:
https://www.deepblueyachtsupply.com/mic ... -boat-prop
This 11" prop would spin up to about 7000 rpm, although I never did take it up that high. The 15" prop only spun to 5000 rpm. With the 13 prop, it is perfect at 5800 rpm, which makes sense....the results are right in between that of the other 2 props.
We could analyze it to death, but frankly, I'm done with it now. It's performing well, and about the same as EZ's 26M with a 13" prop, which is a similar setup to mine. I believe his boat also has bottom paint, which may be the critical factor in all this.
Time to move on to many other things I need to take care of, such as an ailing trailer.
I do appreciate all the help