MudMotor improvement talk

[Steven Alexander]

So as to not hijack another thread...

I love this kind of stuff.... Ill bite.

So I am going to go real world here. My havoc hull I had custom made with a little thicker aluminum. I figure the hull weighs around 750 lbs. My mudmotor is the big boy and it weighs 312 lbs according to JD power. So lets say my entire rig weighs 1050 lbs. Big ol heavy sucker, but I actually move it around with ease by myself in only a 12-16 inches of water. Anything less than a foot, I am grabbing the winch out of the box or hoping I have an extra set of hands lol. I have a 9 gallon tank, so full full thats an extra 72lbs. I wont take into account any of the gear or dogs or humans. Let just play hypothetical hull for hull. So we can comfortably say 1125 lbs in weight for my current rig.

I know this is kind of apples to oranges but the battery cell in a tesla is 1200 -1700 lbs. I am not saying you need a battery cell that big. I did figure out I use 3 gallons of gas for 27 miles of travel in my boat, fully loaded. So with 9 gallons I am traveling ~80 miles. Obviously a tesla battery cell should go a LOT further than that because these cars go 100's of miles before needing a charge (I think, and definitely just assuming a bit here). A quick google search shows 250-275 miles on a full charge for Teslas battery cell. So for math purposes, lets do roughly the same conversion from miles travel to weight, using tesla battery cell numbers. If I wanted a battery cell to go 80 miles, I will take 1200-1700 and divide it by 3.5ish, (I am doing really really rough numbers here). The battery cell alone would weigh 350-480ish lbs. Now we are not taking into account the motor to push the hull forward. So weight for weight.... we are semi close to what my mudmotor weighs, but the electric is still heavier.

Here is the kicker though... Mercury has already made some really small electric outboards. So I looked at one of their motors. The 7.5 hp motor weighs 43 lbs without battery and the battery weighs 17 lbs so a total of 60lbs for a 7.5 hp motor. So we can say that for every 8lbs we get 1hp of electric motor. A 50hp motor (same hp rating as my mudbuddy) would weigh 400 lbs. Pretty close to what I figured out using the Tesla hypothetical above. Here is what shocked me.... A fully charged motor only runs for 5 miles at full throttle before needing another charge. I would have to charge that sucker 3 times just to get to one of my hunting holes from the ramp.

So basically, I wrote all this..... and its just a big waste of everyones time lol.

It's not a waste of my time, buddy. I've spent my life as an army engineer. This is the kind of stuff that keeps my mind racing at night.

As my idiot brain understands it; There is no equivalent HP to HP comparison of an electric to IC motor comparison. As in, a 3HP 3000RPM electric motor will absolutely DESTROY a 3HP IC engine running at 3000RPM. Probably 3-4x stronger. That 7.5e isn't a 7.5HP electric motor. Far from it. It's equivalent to a 3.5HP "kicker" motor. I'm not even sure where the 7.5 comes from, except it's got a rated output of 750W. 735W is equivalent to a 1HP electric motor. Your trolling motor is likely more powerful.

As for the running time/distance, we all agree that batteries have some more warts to overcome. And that electric Merc also says this:

Range & Runtime​

Based on testing with a 13-foot Veer™ V13 boat (382-pound dry weight), the Avator 7.5e electric outboard can run for 60 minutes or 5 miles at constant full throttle, with one fully charged 1kWh battery, and up to 19 hours or 34 miles at constant 25% throttle. Range and runtime may vary. Environmental conditions, boat type and load can influence performance.

So, carry a spare 17 lb battery and motoring to/from the duck hole would be do-able for many. The batteries drop in like a cordless drill battery.

 

[William Reinicke]

So as to not hijack another thread...


It's not a waste of my time, buddy. I've spent my life as an army engineer. This is the kind of stuff that keeps my mind racing at night.

Ya I am kind of nerd who knows a whole lot of nothing. So I am nowhere near as bright as an engineer brain. I just try and work with real world experience. Hence the comparisons from my hull and weight vs the tesla fuel cell weight and range.

As my idiot brain understands it; There is no equivalent HP to HP comparison of an electric to IC motor comparison. As in, a 3HP 3000RPM electric motor will absolutely DESTROY a 3HP IC engine running at 3000RPM. Probably 3-4x stronger. That 7.5e isn't a 7.5HP electric motor. Far from it. It's equivalent to a 3.5HP "kicker" motor. I'm not even sure where the 7.5 comes from, except it's got a rated output of 750W. 735W is equivalent to a 1HP electric motor. Your trolling motor is likely more powerful.

I agree with this and I knew I would be called out trying to go from HP to HP but thats how my brain works. I will have to completely trust your knowledge on this one. And you're saying my tm motor is more powerful than that "7.5 hp" electric motor.... look at the size of that thing for being less powerful than my trolling motor. Hard for me to believe. Also, in the last post, I was more making the point of weight of a battery cell to try and achieve the same abilities as my mudmotor. Likely, my train of thought, is completely skewed in how I am trying to justify an electric motor on a duck boat.

As for the running time/distance, we all agree that batteries have some more warts to overcome. And that electric Merc also says this:

Range & Runtime​

Based on testing with a 13-foot Veer™ V13 boat (382-pound dry weight), the Avator 7.5e electric outboard can run for 60 minutes or 5 miles at constant full throttle, with one fully charged 1kWh battery, and up to 19 hours or 34 miles at constant 25% throttle. Range and runtime may vary. Environmental conditions, boat type and load can influence performance.

So, carry a spare 17 lb battery and motoring to/from the duck hole would be do-able for many. The batteries drop in like a cordless drill battery.

I would have to carry 5 extra batteries lol. One of my duck holes is a 15 mile run. 3 batteries there, 3 batteries back lol.

What do you think a spare battery cost?? I know how much a spare lithium battery runs for power tools and they are the expensive part of the tool. Duck hunting is going to get a ton more expensive if we have to play this game.

 

[Steven Alexander]

Likely an outrageous price on spare batteries (and that outboard, too). But, I would imagine you wouldn't need to WOT all the time. That 7.5 e-motor can go 34 miles at quarter-throttle. Probably make your 15 miles on a battery, and back on the other, running 50-60% throttle. Personally, I'd take a speed reduction for a silent motor. And again, "it ain't for everybody" is a real thing. I'm talking about quieting a MM frame for the folks that just have to have one of them in the timber, not running miles and miles of open water in one.

The "size" of that 7.5e has most to do with the battery compartment up top. The motor is in the foot, like a trolling motor, and the battery slides into the top of the motor. Imagine if you had to put 2-3 12V deep cycle batteries on top of your (24-36V) trolling motor and not in the transom. The overall size would grow significantly.

And you're saying my tm motor is more powerful than that "7.5 hp" electric motor

It is not a 7.5HP electric boat motor. It's a 1.1HP electric boat motor that is equivalent to a 3.5HP gas motor. Their labeling of 7.5 is misleading, but looking at their bigger e-motor options, the number represents the kW output of the motor (750w/.75kW). They also have a 11.0kW (15HP) and a 7.5Kw (10HP). They put the 11.0kW behind an 18' sun tracker party barge pontoon. Range at half throttle was 20 miles. We ran ours with a 90HP motor and it didn't feel like we went much over 20 miles between fill-ups with a 18 gallon tank.
Again, not advocating everyone switch to an e-motor. Far from it. I just want quiet in the woods, and I want them kids to get off my lawn.

 

[William Reinicke]

Likely an outrageous price on spare batteries (and that outboard, too). But, I would imagine you wouldn't need to WOT all the time. That 7.5 e-motor can go 34 miles at quarter-throttle. Probably make your 15 miles on a battery, and back on the other, running 50-60% throttle. Personally, I'd take a speed reduction for a silent motor. And again, "it ain't for everybody" is a real thing. I'm talking about quieting a MM frame for the folks that just have to have one of them in the timber, not running miles and miles of open water in one.

Not me, I am wanting speed for a couple reasons. 1) I get to sleep in later with a faster boat. My first duckboat was a 12-15 mph boat. I had to get to some lakes at like 5 am to be at the hole in time to hunt. It sucked! 2) Windy conditions. There is nothing worse than not having the speed to stay on top of big waves. Once you are too slow and you fall down into the wakes, you take every wave pounding the front of the boat. My current setup will run 20-25 mph winds pretty comfortable. Once I hit 30 mph winds, I am taking it in the bow and getting wet. Love the hull I have, as I have been in 40 mph winds and never felt unsafe, just really soaked is all.

I get what you are saying about quieting down in a timber hole. But not even that necessarily makes sense either as flooded timber is more about racing now. So no one wants a slower boat these days.

The "size" of that 7.5e has most to do with the battery compartment up top. The motor is in the foot, like a trolling motor, and the battery slides into the top of the motor. Imagine if you had to put 2-3 12V deep cycle batteries on top of your (24-36V) trolling motor and not in the transom. The overall size would grow significantly.

Yup that makes sense now.... STUPID! Might as well find a way to incorporate a battery hook up to the batteries inside the boat and keep the actual motor much smaller. I dont like this design at all.

It is not a 7.5HP electric boat motor. It's a 1.1HP electric boat motor that is equivalent to a 3.5HP gas motor. Their labeling of 7.5 is misleading, but looking at their bigger e-motor options, the number represents the kW output of the motor (750w/.75kW). They also have a 11.0kW (15HP) and a 7.5Kw (10HP). They put the 11.0kW behind an 18' sun tracker party barge pontoon. Range at half throttle was 20 miles. We ran ours with a 90HP motor and it didn't feel like we went much over 20 miles between fill-ups with a 18 gallon tank.
Again, not advocating everyone switch to an e-motor. Far from it. I just want quiet in the woods, and I want them kids to get off my lawn.

The sad truth though.... I would give anything to have a quiet electric mud motor that was capable of what my mudmotor does now. The instant power on electric is what I would love to have. I bet it would be a rocket in the marshes. What you typed here makes a lot of sense. So real world, my first mudmotor was a kohler 20 (if I remember right) and it took me every bit of 45 minutes to get to the same marsh that is 15 miles from the ramp. If there was any weather, better account for an hour or more. I only did it a couple times, as if I got caught in wind, I was a dead man in that boat. That boat had a 6 gallon tank and it sipped fuel compared to this hopped up 50 hp mudmotor I have now. I could make that run, there and back, twice before I needed to fill up that 6 gallon tank. I can make it almost there and back twice with the motor I have now, but its a 9 gallon tank in this boat and its a 2.5x faster. Ill spend a little more in fuel to get there in a much quicker fashion.

 

[Steven Alexander]

But not even that necessarily makes sense either as flooded timber is more about racing now.

It isn't supposed to be about that, but you aren't wrong. FTR, I run an 8HP 4-stroke OB on a 14' boat in the timber now (when I use a boat at all).

Yup that makes sense now.... STUPID! Might as well find a way to incorporate a battery hook up to the batteries inside the boat and keep the actual motor much smaller. I dont like this design at all.

The 10 and 15HP models do just that. The batteries store where a fuel tank and the trolling/starting batteries would be. Only the 1.1HP model has a battery that slides in.

The sad truth though.... I would give anything to have a quiet electric mud motor that was capable of what my mudmotor does now.

And I wish I had a pair of gloves that were waterproof, warm, and gave me the same dexterity as not wearing gloves. We will likely fill up one hand with shit long before the other is filled with those wishes.

Ill spend a little more in fuel to get there in a much quicker fashion.

Are airboats legal in your state? If so, skip the foreplay and go balls deep on dry ground with a big-block chevy.

SOLD – 2018 16′ x 8′ AirRanger RHINO Edition

www.americanairboats.com

 

[William Reinicke]

It isn't supposed to be about that, but you aren't wrong. FTR, I run an 8HP 4-stroke OB on a 14' boat in the timber now (when I use a boat at all).

The 10 and 15HP models do just that. The batteries store where a fuel tank and the trolling/starting batteries would be. Only the 1.1HP model has a battery that slides in.

What is the true conversion of hp on the 10 and 15 models?

And I wish I had a pair of gloves that were waterproof, warm, and gave me the same dexterity as not wearing gloves. We will likely fill up one hand with shit long before the other is filled with those wishes.

Wear a pair of medical gloves under some good dexterity hunting gloves... you will thank me later.

Are airboats legal in your state? If so, skip the foreplay and go balls deep on dry ground with a big-block chevy.

SOLD – 2018 16′ x 8′ AirRanger RHINO Edition

www.americanairboats.com

Had an airboat. It was junk. I got towed back more times than I care to admit. Its a part of my life I hope to never remember again. I will never go back to one..... And the one I would need, would be WAY expensive. I actually looked into it at one point .

 

[Steven Alexander]

What is the true conversion of hp on the 10 and 15 models?

735ish W = 1HP

11000w÷735w=15, etc.

But HP isn't what matters given the scenario. That "15HP" motor could likely spin a massive prop if you wanted. It wouldn't bog down like a gas motor with a giant prop would. So, there are more considerations than just HP. That's just one.

Wear a pair of medical gloves under some good dexterity hunting gloves... you will thank me later

I tried that. My hands would sweat, then get clammy, then cold. I just use my pockets anymore.

Had an airboat. It was junk. I got towed back more times than I care to admit. Its a part of my life I hope to never remember again. I will never go back to one..... And the one I would need, would be WAY expensive. I actually looked into it at one point .

Pretty simple design. Constant motor issues? That sucks. They are illegal here, IIRC.

 

[William Reinicke]

Mine was a lemon. Work for 2 hunts and then something would pop on it. Did that for almost a year and a half and called the company and we went back and forth, but ultimately they took it back Never again I said.... Never again. Thats all I will say about my airboat experience.