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I have had it with Outboards, Time to go Electric

7K views 61 replies 23 participants last post by  mbianka 
#1 · (Edited)
My outboard has kicked the bucket again. 3 year old engine. Bought new, shop maintained, 4 stroke.

In the last week I have sailed into 2 unknown marinas sailed out of 2 unknown marinas and sailed into 2 unknown coves because my outboard just wouldn't run.

Any way, wife said sell that xxxxxxx outboard and lets figure something else out.

Any way. Thinking about going electric. I know several here have done the same. The boat is only 900 pounds, 21 feet.

I am not sure if I have a question but curious if there is any feed back.

Already on the boat is 20 watts of solar and an 80 AH agm. I own a 35 lb trollling motor. It will push the boat to a couple of knots, i might end up upgrading to a 55. Thats plenty for me for docking.

I don't see any need for mechanical propulsion on open water. The boats sails way better than it motors. Even in light air (sail area displacement ratio of 33).

I don't have much room for solar. I figure I can swap the 20 on the bow for a 40. 40 on top of the forward hatch and maybe 75 on top of the companion way. Thats 135 watts.

Plus, if I am getting rid of outboard and gas, i can take that space and weight alottment for another battery. Big battery I am thinking. That should give me better range. 5 miles would be nice for dead wind and canals.

So thats what I am thinking.
 
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#3 ·
I have a Minn Kota 74lb thrust trolling motor on my Catalina 22. The boat is probably 2,500 lbs and the motor will push it between 3-4 knots at wide open, and still about 3 knots at half.

The 74 lb thrust is plenty for me. I’ve motored into strong headwinds and I’ve towed other boats and it’s never been a problem.

If I were you I would go with a 55 lb motor so that you could stay 12-volt. That simplifies things a lot.

I have two group 31 batteries in series to give me 24 volts. I have a 50 watt solar panel and a Genasun MPPT controller. On a good sunny day I probably get 20-30 minutes worth of half throttle motoring out of the solar panel. But that’s more than I usually motor, so it’s not an issue.
 
#4 ·
I am building a solar system for my truck now so have a little knowledge on solar and battery needs.
I think what you are doing would work as long as you are only planning on using this for day sailing or will stop in port each night to charge your battery(s) each night. This factoring in you are using your motor each day. This would change if you don't motor much each day. I just looked and found video the 55lb thrust motor draws between 7 and 32 amps depending on settings.

I don't think you will get much more out of a larger solar panel. I would invest in more batteries and an appropriately sized charger. You could buy the electric motor and test the needs with your current battery for power settings to determine your future battery needs.
 
#5 ·
I am not sure about a charger working for me. In the 3 years or so I have owned this boat I have only stayed in a marina 1 night.

I do visit marinas, but usually only to get supplies. Todays visit was because my wife ran out of Olives for her martinis. So we stopped at the gas dock for an hour to run to the dollar store. Not long enough to charge batteries.
 
#6 ·
I am still learning so take what I say with a grain of salt and double check my numbers.

A large expensive battery charger will top off your batteries quicker. Other options a Lithium battery will charge very quickly and be lighter per Amp hour. Expect to spend about 10 per amp hour so $500 for a 50AH lithium battery.

The problem you will have with an electric setup is doing multi-day cruises without marina visits. Anytime you need to use max power from the electric will drain your battery significantly.
 
#8 ·
I too have the 5 HP Tohatsu propane outboard which starts everyone, no drama. Your challenge with electric is going to be recharging the batteries which I believe makes it incompatible for your application. I suggest you give propane some consideration.


Sent from my iPhone using Tapatalk
 
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#10 ·
After my Honda 2.5 four stroke went to the bottom during Hurricane Sandy I went electric in the dingy after having done the same with the in board diesel ten years before. I use an Electric Paddle Carry model. Much lighter and reliable than the gas outboard. Charge the battery with a small 300 watt 12 volt sine wave inverter or 120 volts if I fire up the generator. Stores below the cockpit with no gas or fluids to worry about leaking out.
 
#11 ·
I think you need to understand that solar only returns full charging power for a few hours a day, not all day long. A 120-watt solar panel may only give you the full 10 amps a couple of hours a day.
Needless to say, on less than full sunny days, you'll get a whole lot less.
My point is that relying on solar for your power needs is iffy at best and a good shore power fed battery charger would be a good investment as a back-up. A windgen is even less reliable, averaging about 1/3 amp per hour, even here in the tropics where a fairly reliable wind is common.
I'd be more inclined to bite the bullet and buy a Yamaha and have a reliable motor when you need it and should run trouble-free for a good many years, if well maintained.
 
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#17 ·
I think you need to understand that solar only returns full charging power for a few hours a day, not all day long. A 120-watt solar panel may only give you the full 10 amps a couple of hours a day.
Needless to say, on less than full sunny days, you'll get a whole lot less.
Doesn't that 10 amp an hour also assume the optimum angle to the sun from the solar panel? While sailing or if shaded by a sail there will be much less amps stored per day.

My solar has only been setup a few days, I am still learning it's potential. I have a 50watt panel that is processed by a hight end MPPT solar charger available on a stand outside my truck that I rotate and re-angle to get the most sun possible and have only gotten 160watt hours on the best day.
 
#13 ·
We had a 3.5 hp Tohatsu that we bought new. Worked ok for 1/2 season and then was a piece of crap. We sold it and bought a Honda 2.3 and this time we used nothing but ethanol free gasoline, even ponying up for Tru Fuel when we were based in Connecticut.

It’s noisy but it starts in the first pull or two every time and hasn’t given us a bit of trouble in 3 years. Now let me go look for the nearest piece of wood to knock on.
 
#16 ·
We had a 3.5 hp Tohatsu that we bought new. Worked ok for 1/2 season and then was a piece of crap. We sold it and bought a Honda 2.3 and this time we used nothing but ethanol free gasoline, even ponying up for Tru Fuel when we were based in Connecticut.

It's noisy but it starts in the first pull or two every time and hasn't given us a bit of trouble in 3 years. Now let me go look for the nearest piece of wood to knock on.
The engine in question is a 2016 Honda 2.3.
 
#14 ·
I believe that I see the problem here;

My outboard has kicked the bucket again. 3 year old engine. Bought new, shop maintained, 4 stroke.
I am using a 2005 Tohatsu 3.5 2-stroke, rebadged as a Mercury 3.3, that I bought used in 2011. I have had to lube the shifter, clean the carburetor, change the lower unit oil, replace the shear pin after I hit a rock (twice), replace some gaskets and replace the sparkplug in my 9 years of ownership. I do ALL the maintenance myself! I am considering buying another as a spare (should cost ~$300). I love that this thing weighs <30lbs and starts on the second pull. I keep a spice jar under the cowl that contains; a sparkplug wrench, a sparkplug and a spare shear pin, some emory cloth and a zip-tie. That's my emergency tool kit.

In the early '80s I used to work at a hardware store that sold 2-stroke (Lawn-Boy and Fly-Mow) lawnmowers. When people would drop their mowers off in the late fall or early spring for a tune up, the owner of the business would spray carburetor cleaner on the mower, and wash it with a hose. He would then charge them for a full tune up. My mooring neighbor has paid somone to fix a carburetor leak twice. Both times he has instructed the shop to not tune it, but just fix the leak. Both times the motor has been returned a little cleaner, and with a $200+/- bill, and it is still leaking. This time he has decided to fix it himself.
 
#15 ·
I haven’t tested the limits of my setup, but here are my calculations:

Two group 31 batteries wired in series gives me 105 amp hours at 24 volts = 2,520 watt hours

Don’t want to run the batteries below 50% so useful power = 1,260 watt hours

Motor draws 25 amps at half throttle = 600 watts

3 knots at half throttle so range = 6 nm
(or 12 nm in an emergency if I
were willing to murder the batteries)



50 watt solar panel with MPPT controller on an OK day = 200 watt hours

Ranger under solar power = 1 nm / day



Your boat with passengers will weigh about half what my boat weighs. Does that mean you’d get twice the range? I have no idea. But let’s say it does, let’s say your smaller boat can make 3 knots on a 55 lb thrust motor drawing 25 amps at 12 volts.

That would give you a range under battery of 12 nm. If you went up to 135 watts of solar, you’d get a daily range of 5.4 nm from solar charging.

It seems like 5 nm a day with 12 in reserve would probably be enough for your kind of trips, where you’re almost always under sail.



Although this would be 120 lbs of battery and 10 square feet of solar panels on an 800 lb boat, so.....
 
#20 ·
I should add, I have tested my boat with the 80 ah battery and trolling motor. That is how the boat came and how the previous owner used it. I think his useage was similar to mine, but shorter trips.

It seems to me the current battery gives me about 2 miles of motoring which I figure should be good for maybe 8 dockings, so I call that 4 days.

A 12 mile range as Minn described would be pretty awesome. That might give me 3 weeks use without any charging capacity what so ever.

I am thinking half that would match my useage pretty well. I figure if I could get the equivalent of 1 mile a day charging, that should work.

There are days where we wouldnt use the battery at all. Todays a perfect example. We are stopped on an island just swimming for the day. The boat isn't going any where.

One of the power boaters on the island just came by and let me know he would be running his generator for an hour if we needed to charge anything. So that sort of thing happens too.

I guess it would make sense to bring a plug in charger too.

My boat will paddle at close to a knot with a SUP paddle. But that really kind of sucks and I would rather sail into dock than paddle if there is any wind at all. But motoring into dock beats either option by a mile.
 
#24 ·
Figuring how much solar you'll need or can generate (between room for solar panels and batteries to store it) has a lot of variables, the biggest being clouds. On the other hand many of us here are using solar so there is a lot of advice available.
Solar panels refer to watts and most of the larger panels output 17-18 volts from the panel before that power gets to the charge controller, so the amperage calculation is watts divided by volts = amps. 100 watts divided by 17 volts is an output of 5.8 amps when conditions are just right. Most calculations seem to figure an average of about 5-6 hours of good solar exposure per day. Clouds, shadows, shifting axis, all effect that output. Wire size, distances, battery condition effect what gets to the batteries and charging.
The bottom line is 100 watts of solar panels will put about 32 amps into your battery per day, 200 watts about 64 amps, etc....

From Boat US - " To use an example, a 55 lb thrust motor unit has a peak power draw of 40 amps. If you use the trolling motor for 6 hours at average 50% load of 20 amps, the trolling motor will then require a battery load of 120 Ah. (6 hours X 20 amps=120 amp hours)."

Second issue is the size of the battery or batteries -
from Calculating Motor Run Time - TrollingMotors.net
The larger the rating, the more power the battery can hold, and the longer it will be able to power a motor at a given speed. For example, a 100 amperage hour battery is one that would be able to supply 25 amps of power for 4 hours (25 amps * 4 hours = 100 amp hours) before running out of energy.


Running a battery too low shortens its life, to consistently run 100 amps from the battery bank you'd probably want 400-600 amp capacity, like 2 Trojan T 105s in series (great batteries but 64 pounds each). Unfortunately if you use the motor during the daylight hours it won't charge at night, so the next morning you have depleted or dead batteries.

All this is why I really appreciate my little Suzuki 2hp 2 stroke (and use the solar system to keep the refrigerator cold).
 
#28 ·
My experience exactly mimics Fattys. When in New England during summer the solar way out performs the D400s. When in windwards for winter the wind way out performs the solar. Have two panels mounted on top of hard Bimini so never shadowed. Have two D400s mounted on 10’ poles so always in direct wind.
Explanation is longer days in summer and stronger wind in tropics. We anchor. When in a slip production falls for both. Less wind and usually more dirt in the air.
 
#32 ·
I recently bought an e-Propulsion Spirit for my 9’ Zodiac tender and my 19’ Flying Scot day sailer. It works great! With 6 adults in the Flying Scot I can motor around in silence at 4 knots. Last week ghosting through the harbor under sail I would flip on the Spirit to move between cat’s paws of wind. That must have driven the other sailors nuts cause I was scooting along in silence while they were in a dead calm. Love the silent power and the safety from gas cans and oil spills.tiller gauge tells me remaining duration at current speed so there are no surprises.
 
#34 ·
I'm going to give the same advice here, as I gave my daughter, when she wanted to transfer in college.

Be sure you are running toward something, not away from something.

If you really like electric, go for it. If it's only because you're upset with the outboard, I'd address that first.

There is another hiking line, if we're really getting zen here. The saying goes, you should only leave the trail and discontinue the hike, on a good day, never a bad day, to be sure it's really what you want to do.

There is absolutely no good reason a three year old outboard should be unreliable. Your call, of course. Electric is just fine too. Be sure your motivations are sound.
 
#35 ·
My outboard has kicked the bucket again.

Any way. Thinking about going electric. I know several here have done the same. The boat is only 900 pounds, 21 feet.

I am not sure if I have a question but curious if there is any feed back.

Already on the boat is 20 watts of solar and an 80 AH agm. I own a 35 lb trollling motor. It will push the boat to a couple of knots, i might end up upgrading to a 55. Thats plenty for me for docking.

I don't see any need for mechanical propulsion on open water. The boats sails way better than it motors. Even in light air (sail area displacement ratio of 33).

I don't have much room for solar. I figure I can swap the 20 on the bow for a 40. 40 on top of the forward hatch and maybe 75 on top of the companion way. Thats 135 watts.

Plus, if I am getting rid of outboard and gas, i can take that space and weight alottment for another battery. Big battery I am thinking. That should give me better range. 5 miles would be nice for dead wind and canals.

So thats what I am thinking.
The youtube channel Sailing UMA - they have all electric including a torqueedo outboard and they just did a bit of narrative on how great that outboard is.

15:50 they talk about it a bit, looks very cool.

 
#37 ·
If you can match your motoring needs with a motor and have large enough batteries and enough alternate charging then it's a good solution. Seems to me that electric motors requires lots of amps and this equates to lots of AH in the batts which is heavy... and efficient solar to replenish the batts.

If you are trailering the boat, you might be able to top up the batteries from the car/truck and certainly from a shore charge where the boat is stored. If you don't have to use the motor much it might work. But I am doubtful.

We need solar sails and deck surface which charge batteries.
 
#38 ·
Of course Minnewaska is right; a 3 year old outboard should not be given up on. Its probably just a plugged up carb.

One reason I would switch to electric is that while motoring out I have to listen to the drone of the outboard. Its such a balm for my ears to shut it down and just sail.

But my 10 year old Tohatsu 5 is really fantastic ( except for the sound) and I am not giving it up without a plan.
 
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