E-tech Prop
E-tech Prop
Any ideas on the prop configeration, size pitch etc, or even part number to suit our particular boat??
You want a 14 inch diameter prop.
Pitch is somewhat dependent upon how you are loaded. If you are really heavy, then you need a 9 pitch. But, for lighter loads, the 9 pitch will run the RPM up to ~6k. So, for lighter loads, you'll want an 11 pitch, which will put the RPMs down near the lower WOT RPM range, at least on my 40hp... 10 pitch is more ideal, for me...
If you have a 50hp or better, then you probably don't want to go below a 10 pitch and an 11 pitch is probably ideal, until you get into the 75+hp...
Stay away from the cupped blades. I have been very dissappointed with any cupping. Furthermore, the blades that have been designed to be cupped, are just total crap, on this boat. They don't do well out of the box and do even worse with the cupping removed...
I'd recommend the older style houseboat-type props.
I'm pretty happy with my 14x11. Sorry I can't seem to find the part #, although it might be 012047. If you want a 9 pitch, I'm pretty happy with my OMC 383160.
Pitch is somewhat dependent upon how you are loaded. If you are really heavy, then you need a 9 pitch. But, for lighter loads, the 9 pitch will run the RPM up to ~6k. So, for lighter loads, you'll want an 11 pitch, which will put the RPMs down near the lower WOT RPM range, at least on my 40hp... 10 pitch is more ideal, for me...
If you have a 50hp or better, then you probably don't want to go below a 10 pitch and an 11 pitch is probably ideal, until you get into the 75+hp...
Stay away from the cupped blades. I have been very dissappointed with any cupping. Furthermore, the blades that have been designed to be cupped, are just total crap, on this boat. They don't do well out of the box and do even worse with the cupping removed...
I'd recommend the older style houseboat-type props.
I'm pretty happy with my 14x11. Sorry I can't seem to find the part #, although it might be 012047. If you want a 9 pitch, I'm pretty happy with my OMC 383160.
Convert to Prop RPM so you can use other prop data to get cl
Convert to Prop RPM so you can use other prop data to get close. Then look at the E-Tec high thrust props here, (why no pitch charts? ask your E-Tec dealer.)
http://www.evinrude.com/en-US/Accessori ... ers&page=1
..
It is the Prop RPM, not the engine RPM that counts when figuring out the correct pitch prop. Example: The Honda BF50 2.08 gears and 6000 RPM is equal (more or less) to the Suzuki DF50 2.27 gears and 6500 RPM. These are very different than the BigFoot / High Thrust outboards with 2.33 gears and a larger diameter prop. And just as different from the Tohatsu with 1.85 gears and 5850 RPM. The Tohatsu needs something like a 7 pitch which the Honda and Suzuki need a 9 pitch, and IIRC the BigFoot takes a 10 pitch in the bigger diameter.
..
With approx. 50hp consider the Mac26X is way underpowered for a powerboat, so no worries about losing efficiency due to too big a diameter prop. That sort of stuff only matters for fast boats.
..
The E-Tec 50hp uses a 2.67 gear and runs to 6000 RPM. So the prop RPM is 6000/2.67 = 2247 PropRPM
..
E-Tec 2247 PropRPM [look at the others and make a guess]
Suzuki 2863 PropRPM 9 pitch 4 blade (Honda/Solas 58134-ZV5-009AH)
Honda 2885 PropRPM 9 pitch 4 blade (Honda/Solas 58134-ZV5-009AH)
Tohatsu 3162 PropRPM 7 pitch four blade 11.3 dia. (Tohatsu 34864-1080M)
Nissan 3162 PropRPM 7 pitch four blade 11.3 dia. (Tohatsu 34864-1080M)
BigFoot 2575 PropRPM 10 pitch three blade 14 dia.
HighThrust 2575 PropRPM 10 pitch three blade 14 dia.
..
http://www.tohatsu.com/tech_info/prop1.html
http://www.honda-marine.com/acc.aspx#
http://www.mercurymarine.com/50_efi_bigfoot
http://www.evinrude.com/en-US/Engines/2 ... ations/50/
http://www.yamaha-motor.com/outboard/pr ... specs.aspx
..
Here is an E-TEC boat test where the boat is too heavy to really get going with 50hp, so maybe the prop they used 3 blade 13 pitch 14 dia. will be pretty close to the Mac26X. However, I would have changed the tested boat to a 12 pitch to get closer to the top of the RPM range, horsepower is proportional to RPM, and I rather run faster RPM and less torque for less wear on the motor and gears. So, with this test I am guessing that the E-TEC will be fine on the Mac26 with a 12 pitch 14 inch diameter prop, and the wide open throttle RPM will be around 5500 with ballast full aand closer to 6000 RPM with ballast empty. 11 pitch might be better with full ballast.
http://www.evinrude.com/en-US/Engines/2 ... end+RE.htm
The boat is a pontoon http://www.newboats.com/product.jsp?ID=6467 designed for 90 hp. The Mac26 would also do well with 90 hp IMHO.
http://www.evinrude.com/en-US/Accessori ... ers&page=1
..
It is the Prop RPM, not the engine RPM that counts when figuring out the correct pitch prop. Example: The Honda BF50 2.08 gears and 6000 RPM is equal (more or less) to the Suzuki DF50 2.27 gears and 6500 RPM. These are very different than the BigFoot / High Thrust outboards with 2.33 gears and a larger diameter prop. And just as different from the Tohatsu with 1.85 gears and 5850 RPM. The Tohatsu needs something like a 7 pitch which the Honda and Suzuki need a 9 pitch, and IIRC the BigFoot takes a 10 pitch in the bigger diameter.
..
With approx. 50hp consider the Mac26X is way underpowered for a powerboat, so no worries about losing efficiency due to too big a diameter prop. That sort of stuff only matters for fast boats.
..
The E-Tec 50hp uses a 2.67 gear and runs to 6000 RPM. So the prop RPM is 6000/2.67 = 2247 PropRPM
..
E-Tec 2247 PropRPM [look at the others and make a guess]
Suzuki 2863 PropRPM 9 pitch 4 blade (Honda/Solas 58134-ZV5-009AH)
Honda 2885 PropRPM 9 pitch 4 blade (Honda/Solas 58134-ZV5-009AH)
Tohatsu 3162 PropRPM 7 pitch four blade 11.3 dia. (Tohatsu 34864-1080M)
Nissan 3162 PropRPM 7 pitch four blade 11.3 dia. (Tohatsu 34864-1080M)
BigFoot 2575 PropRPM 10 pitch three blade 14 dia.
HighThrust 2575 PropRPM 10 pitch three blade 14 dia.
..
http://www.tohatsu.com/tech_info/prop1.html
http://www.honda-marine.com/acc.aspx#
http://www.mercurymarine.com/50_efi_bigfoot
http://www.evinrude.com/en-US/Engines/2 ... ations/50/
http://www.yamaha-motor.com/outboard/pr ... specs.aspx
..
Here is an E-TEC boat test where the boat is too heavy to really get going with 50hp, so maybe the prop they used 3 blade 13 pitch 14 dia. will be pretty close to the Mac26X. However, I would have changed the tested boat to a 12 pitch to get closer to the top of the RPM range, horsepower is proportional to RPM, and I rather run faster RPM and less torque for less wear on the motor and gears. So, with this test I am guessing that the E-TEC will be fine on the Mac26 with a 12 pitch 14 inch diameter prop, and the wide open throttle RPM will be around 5500 with ballast full aand closer to 6000 RPM with ballast empty. 11 pitch might be better with full ballast.
http://www.evinrude.com/en-US/Engines/2 ... end+RE.htm
The boat is a pontoon http://www.newboats.com/product.jsp?ID=6467 designed for 90 hp. The Mac26 would also do well with 90 hp IMHO.
The E-TEC 90 SaltWater now in 20" lower unit length
The 25" version has 2.25 gears. The 20" version has 2.0 gears. I wonder if the 2.0 gears will work well on the Mac26? If not, I wonder if a special order would provide a 20" E-TEC 90 with the 2.25 gears.
http://www.evinrude.com/en-US/Engines/2 ... IN-LINE.3/
Note: The E-TEC 90 takes a 15" prop!
http://www.evinrude.com/en-US/Engines/2 ... IN-LINE.3/
Note: The E-TEC 90 takes a 15" prop!