sgr143
Well-Known Member
Not that's affected its function. I put a coat of hammerite over the motor body when the underlying aluminium started to show through in a few places.
Anyone have real world experience of electric trolling motors used as an outboard?
- Thread starter Adios
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Adios
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are you very careful with it? wash it after every use? The saltwater versions are double the price though there is one cheaper make maybe bison that claims its ok in either.
Nimrod18
Well-Known Member
I do have some experience, with a cheap 30lb ‘freshwater’ motor on my Westerly Nimrod (18ft and circa 600kg displacement), which might benefit your GP14 requirement. However, caveats are important:
First, Rutland Water, so freshwater and not tidal. Second, the 70AH leisure battery gets charged at home and only needs lifting from carboot over back of the transom and into a cockpit locker - dead easy upon arrival. Third, I mainly use it to get to and from the pontoon and in and out of Whitwell Creek - those familiar will know that topography and trees make Whitwell fabulously windless. If the wind on the ‘lake proper’ is so low that it’s not sailable, I have used it to transit the kids to the other side for an ice cream. However, if there is any wind, the sails are employed, so I never need to punch into the wind.
With those caveats in mind:
Flat calm day - 3.8kts.
1:05 of motoring takes me from “10 bars” to “8 bars” on the motor’s battery meter. Have only just installed a voltmeter, so no idea what V that correspond to.
No corrosion.
Mass distribution of the outboard is a bit odd. Most of the mass is in the motor, where the gearbox usually goes. As a result the balance point is about 2/3rds of the way down the leg.
It is beautifully quiet. Perfect for family outings. I have previously left the boat tied up and wandered off for lunch with the prop still ticking over on its slowest setting.
I’ve been using it for 5 seasons now and am entirely satisfied for what I need, as outlined above. In fact last week I added a proper battery box, fuse and isolator switch down below, with a socket at that aft end of the cockpit. This replaced the previous rather gash set up. That all said, I’m hoping to spread my wings from Rutland this summer (fingers crossed) and recognise that, if I go coastal, the trolling motor is staying home and the 2 stroke is coming with me.
My final point - I went down the trolling motor route because Rutland don’t let leisure sailors use petrol. However, in the context of fresh water lakes, no tides and day sailing / weekending, I personally would choose a troller over an outboard on all bar extreme occasions.
That might not address your problem set, but there may be something of use for you.
First, Rutland Water, so freshwater and not tidal. Second, the 70AH leisure battery gets charged at home and only needs lifting from carboot over back of the transom and into a cockpit locker - dead easy upon arrival. Third, I mainly use it to get to and from the pontoon and in and out of Whitwell Creek - those familiar will know that topography and trees make Whitwell fabulously windless. If the wind on the ‘lake proper’ is so low that it’s not sailable, I have used it to transit the kids to the other side for an ice cream. However, if there is any wind, the sails are employed, so I never need to punch into the wind.
With those caveats in mind:
Flat calm day - 3.8kts.
1:05 of motoring takes me from “10 bars” to “8 bars” on the motor’s battery meter. Have only just installed a voltmeter, so no idea what V that correspond to.
No corrosion.
Mass distribution of the outboard is a bit odd. Most of the mass is in the motor, where the gearbox usually goes. As a result the balance point is about 2/3rds of the way down the leg.
It is beautifully quiet. Perfect for family outings. I have previously left the boat tied up and wandered off for lunch with the prop still ticking over on its slowest setting.
I’ve been using it for 5 seasons now and am entirely satisfied for what I need, as outlined above. In fact last week I added a proper battery box, fuse and isolator switch down below, with a socket at that aft end of the cockpit. This replaced the previous rather gash set up. That all said, I’m hoping to spread my wings from Rutland this summer (fingers crossed) and recognise that, if I go coastal, the trolling motor is staying home and the 2 stroke is coming with me.
My final point - I went down the trolling motor route because Rutland don’t let leisure sailors use petrol. However, in the context of fresh water lakes, no tides and day sailing / weekending, I personally would choose a troller over an outboard on all bar extreme occasions.
That might not address your problem set, but there may be something of use for you.
fredrussell
Well-Known Member
Bit cheaper than that these days. My mate got a 100ah lithium battery for £400 (see post #4). He bought it from China via eBay. It’s been good so far. It came with a BMS but a less than impressive charger I seem to recall.
sgr143
Well-Known Member
Not really. Sometimes I dunked it in the freshwater barrel in the boatyard after use, but not very often. Mine is a Bison. Useful, because, as we all know, "yer cain't wash yer 'ands in a Buffalo".
Plum
Well-Known Member
Is the motor/prop shaft stainless steel, please?
sgr143
Well-Known Member
No idea, sorry.
{edit} I just went to have a look at it (it's in the garage, not on the boat at present). The exposed end of the shaft is a bit rusty - not hugely so, but enough to notice. So not stainless, or if it is, a hardenable stainless with relatively low Cr content. Actually, now I think of it, that seems a fairly likely possibility.
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dleroc
Well-Known Member
I liked how peaceful it was although connecting the cable to the terminals each time was fiddly.
Adios
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No thats useful. In your situation its perfect. Would be a shame to spoil it with noise. Is that 1 hour 5 minutes? That seems extremely good if the meter has an relationship to reality. Would be great if you could let me know more when you've used the voltmeter on it. I guess thats not full power? It doesn't take any effort to move a boat slowly through the water does it, the curve rises steeply the faster it goes. Still 3.8knots is a decent speed for that little power consumption.
I guess for strictly tender use noise isn't a problem so the 2 stroke makes sense as its all in one, bolt it on and its done. If using the GP14 as a launch for exploring with the kids I probably need the 2 stroke for that as well. As an auxiliary while sailing I wouldn't be spending long on the motor, or the prime time won't be on motor, so noise not such an issue... I'll probably stick with the 2 stroke
Nimrod18
Well-Known Member
@Athomson.
Affirm 1hr 5min and I think it was at full chat (setting 5) from memory. I have in mind that A on setting 1 is circa 1 amp (considered a solar powered canoe experiment at one point - that number was from some google research), so I think setting 5 was sub 10 Amps. Someone will want to challenge those figures, so please know that it’s been about 4 years since I’ve contemplated them and they are not empirically based. I’ll post here again for posterity, likely after Easter, with V and A data if I can get it.
One additional - I did consider letting kids use the trolling motor with our 2.3m dinghy on the local river. Kill cord was a dissuading issue, as in “didn’t have one”. I did look into getting a kill cord for trolling motors. There was one on Amazon from the USA but it was either unavailable or too expensive. I considered jury rigging one onto the top of a bespoke battery box, using a battery isolator (the sort that has a twisty red ‘flag’ sticking out the top) but dependability was a concern - knowing my practical skills, sequence of events would have been: casualty falls overboard; hydrodynamic drag makes casualty drag behind boat; kill cord pulls very taught; battery switch fails to turn off; battery box gets ripped from its mounting and falls overboard, still attached to casualty; battery box rapidly sinks, pulling kill cord taught in exactly the wrong direction...
I think if I was in your shoes, with the requirements you have, Ocham’s razor says a dinky 2 stroke.
Affirm 1hr 5min and I think it was at full chat (setting 5) from memory. I have in mind that A on setting 1 is circa 1 amp (considered a solar powered canoe experiment at one point - that number was from some google research), so I think setting 5 was sub 10 Amps. Someone will want to challenge those figures, so please know that it’s been about 4 years since I’ve contemplated them and they are not empirically based. I’ll post here again for posterity, likely after Easter, with V and A data if I can get it.
One additional - I did consider letting kids use the trolling motor with our 2.3m dinghy on the local river. Kill cord was a dissuading issue, as in “didn’t have one”. I did look into getting a kill cord for trolling motors. There was one on Amazon from the USA but it was either unavailable or too expensive. I considered jury rigging one onto the top of a bespoke battery box, using a battery isolator (the sort that has a twisty red ‘flag’ sticking out the top) but dependability was a concern - knowing my practical skills, sequence of events would have been: casualty falls overboard; hydrodynamic drag makes casualty drag behind boat; kill cord pulls very taught; battery switch fails to turn off; battery box gets ripped from its mounting and falls overboard, still attached to casualty; battery box rapidly sinks, pulling kill cord taught in exactly the wrong direction...
I think if I was in your shoes, with the requirements you have, Ocham’s razor says a dinky 2 stroke.
Adios
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I share your "if it can go wrong it will go wrong" mentality! Some other method would work though I imagine. Anything to break the circuit.
Your motor seems to be too efficient to be true though. The Yamaha one I linked to is said to be 45lb and 42amp draw https://cdn2.yamaha-motor.eu/prod/product-assets/2020/MS20/Factsheets/2020-MS20_en-GB.pdf Seems unlikely that your 30lb is only drawing 10amp at full power. If it is drawing more like 30amp your 70AH battery should be more like 50% down after an hour. I expect the meter on the motor is being optimistic. But the speed difference between less power and more isn't great. Just pottering around on slow speed a good few hours seems realistic and is a decent amount.
But yes I think I will be sticking with 2 stroke for now. Its either going to be short use in which case noise is ok. Or a good days exploring which I wont have battery power for.
Kelpie
Well-Known Member
I use a Bison 68 on my Avon 310 RIB. The dinghy lives on a pontoon and the motor has been on the back since last autumn; obviously I lift the leg but it's still out on the elements with, so far, no sign of deterioration. I made sure the clamp screws were well greased.
I have been using it with whatever old car battery I happen to have, and charge that a couple of times a month maybe. My mooring is less than 100m from the pontoon so I only need to use it for a minute or so, hence the battery lasts a very long time.
When I borrowed a brand new battery, I was able to get the dinghy up to about 5kt. I'm sure a lighter dinghy with a clean bottom would do better. Anyway it's much faster than rowing and only slightly slower than my 2.5hp 2T. It's also, as others have said, totally silent.
For me the biggest advantage is that I can use it standing up- no more wet bum from rowing!
I have been using it with whatever old car battery I happen to have, and charge that a couple of times a month maybe. My mooring is less than 100m from the pontoon so I only need to use it for a minute or so, hence the battery lasts a very long time.
When I borrowed a brand new battery, I was able to get the dinghy up to about 5kt. I'm sure a lighter dinghy with a clean bottom would do better. Anyway it's much faster than rowing and only slightly slower than my 2.5hp 2T. It's also, as others have said, totally silent.
For me the biggest advantage is that I can use it standing up- no more wet bum from rowing!
billyfish
Well-Known Member
Tried one with a small inflatable, nightmare. Give me a two stroke any day. The motor was fine but the battery is the problem. When they sort that it will be good. Have you seen the French Temo . Brilliant both in idea and price. I'll get one when the Chinese copy it for half the price.....
Adios
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HOW MUCH!? I think at £1500 the English could copy it for half the price. I like the concept though. Bit of 2" waste water pipe full of batteries, probably 18650 lithiums, with a motor glued in the end. I doubt its 80 minutes at full power though as full power looks quite powerful. 5kg including motor doesn't leave much weight for 80 minutes worth of batteries.
Adios
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For that use sounds ideal. The Bisons do claim to be designed for salt water use and it seems enough people have tested it that I have to believe it. As they are cheap enough I think I might look at getting one in addition to the 2 stroke and try it out.