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Re: Pearson P27 Diesel Pulled

 

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We installed an Elco system in a Tartan 34C a few years back. It was a great system and Elco customer service was excellent.?


On Aug 20, 2023, at 6:50 PM, duncan@... wrote:

?Hello,?

New to this group. I just purchased a Pearson P27 1989 model last spring.? The engine is shot.? I pulled it out and had a mechanic take it apart.? He said it is a goner. Since I only have a prop shaft in the sailboat now.? I am thinking of taking this opportunity to do an electric conversion.? Where is the best place to get an 8kw motor with controller?? Also, I need a mount and prop shaft coupling fabricated to make the motor fit the old diesel mounts and prop shaft.??

Thanks!


Re: Pearson P27 Diesel Pulled

 

I have an Electric Yacht QT2.5 (no longer offered publicly, but likely still available if you contact EY) installed on a 3200 lb. catboat for the past three years, and have had no issues with the unit. It is a direct drive (no gear reduction). It is?a?24V system. I got good service during the purchase stage (customized boat power/range charts). The only hiccup was that they delivered a throttle assembly (nice, stainless steel body) which did not have a post/lever. This made actuation while wet difficult. They replaced the part gratis with one which included a stem after a season of use.


On Mon, Aug 21, 2023 at 2:20?PM Richard deVarga <rdevarga@...> wrote:
I recently pulled out a frozen Volvo Penta from a Santana 30/30 GP, so I am also doing research for an 10kw electric propulsion system to get me in and out of a small inland cove marina. I have spent time looking into the Thunderstruck EV 10kw kit and the other systems listed via Plugboats.com. As you will see, the motors and batteries costs very widely. My goal is to try to select a simple system that I can install and maintain by myself. And try to find a system that was manufactured in the USA with a multiyear warranty. I would like to be in the $7000 to 8000 range for the motor kit + lithium batteries. In addition to Thunderstruck, the company I have been investigating is Electric Yachts. I like their QuiteTorque 10kw propulsion system. I am not settled on batteries since the costs and warranties very widely, but very interested on others choices. Please keep us informed of your progress with the system.?



--
Christopher Greenwald
14 Manitoba Rd.
Waban, MA 02468

Cell 617-699-9189


Re: Pearson P27 Diesel Pulled

Richard deVarga
 

I recently pulled out a frozen Volvo Penta from a Santana 30/30 GP, so I am also doing research for an 10kw electric propulsion system to get me in and out of a small inland cove marina. I have spent time looking into the Thunderstruck EV 10kw kit and the other systems listed via Plugboats.com. As you will see, the motors and batteries costs very widely. My goal is to try to select a simple system that I can install and maintain by myself. And try to find a system that was manufactured in the USA with a multiyear warranty. I would like to be in the $7000 to 8000 range for the motor kit + lithium batteries. In addition to Thunderstruck, the company I have been investigating is Electric Yachts. I like their QuiteTorque 10kw propulsion system. I am not settled on batteries since the costs and warranties very widely, but very interested on others choices. Please keep us informed of your progress with the system.?


Re: Pearson P27 Diesel Pulled

 

I purchased my motors, controllers and motor mounts from . They are great to deal with and sell complete kits. You’ll need to calculate the reduction you’ll need to match prop rpm from diesel to electric.?


Re: Pearson P27 Diesel Pulled

 

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I also went electric for my 10M with parts from Thunderstruck.? I fabricated my own motor mounting and reduction drive.? See all sorts of details here:


It is equal to or better in performance to my diesel in every way except range.? Not a concern for my current day-sailing use.?

I would consider the Thunderstruck 10kW kit to re-power a P27.?? They do not have a kit between 5 and 10.? I think the 5kW kit is marginal power for you and the 10kW will have more than enough reserve power for basically no penalty in efficiency.? The 10KW putting out 2kW to cruise won't use any more than the 5kW putting out 2kW to cruise and will run cooler and well within it's capacity.? Trying to punch through a choppy entrance will have the 5kW at max and the 10 happily running at 50% with no concerns about excess heat.?

The battery is going to be the most expensive part of the conversion.? I went with a lithium (LiFePo4) that I assembled from prismatic cells for several reasons all described on the page above.? Chief among them cost per AH of usable capacity of about 1/4 that of drop-in cells.

Dan Pfeiffer


On 2023-08-20 8:20 pm, Circe Strauss wrote:

Check out . I got my motor and controller from them and I'm pretty happy?with it.

On Sun, Aug 20, 2023, 7:50 PM <duncan@...> wrote:
Hello,?

New to this group. I just purchased a Pearson P27 1989 model last spring.? The engine is shot.? I pulled it out and had a mechanic take it apart.? He said it is a goner. Since I only have a prop shaft in the sailboat now.? I am thinking of taking this opportunity to do an electric conversion.? Where is the best place to get an 8kw motor with controller?? Also, I need a mount and prop shaft coupling fabricated to make the motor fit the old diesel mounts and prop shaft.??

Thanks!


Re: Pearson P27 Diesel Pulled

 

Check out . I got my motor and controller from them and I'm pretty happy?with it.


On Sun, Aug 20, 2023, 7:50 PM <duncan@...> wrote:
Hello,?

New to this group. I just purchased a Pearson P27 1989 model last spring.? The engine is shot.? I pulled it out and had a mechanic take it apart.? He said it is a goner. Since I only have a prop shaft in the sailboat now.? I am thinking of taking this opportunity to do an electric conversion.? Where is the best place to get an 8kw motor with controller?? Also, I need a mount and prop shaft coupling fabricated to make the motor fit the old diesel mounts and prop shaft.??

Thanks!


Pearson P27 Diesel Pulled

 

Hello,?

New to this group. I just purchased a Pearson P27 1989 model last spring.? The engine is shot.? I pulled it out and had a mechanic take it apart.? He said it is a goner. Since I only have a prop shaft in the sailboat now.? I am thinking of taking this opportunity to do an electric conversion.? Where is the best place to get an 8kw motor with controller?? Also, I need a mount and prop shaft coupling fabricated to make the motor fit the old diesel mounts and prop shaft.??

Thanks!


Re: advice not on sailing boat

 

I produced this table from the first row and it looks like 48V might be a better solution.
I was basing the 24V suggestion off of your statement that 4kW can hit hull speed.
But that's with no headroom for current/wind/heavy-loads:

72V 3,000rpm 11.5kW
60V 2,500rpm? 9.6kW
48V 2,000rpm? 7.7kW
36V 1,500rpm? 5.8kW
24V 1,000rpm? 3.8kW
12V? ?500rpm? 1.9kW

And 48V is a much more common electric boat battery size compared to 24V.
With around 2:1 reduction you should be able to hit hull speed.? You may actually
be a bit underpropped though, if more like 1,200 prop RPM is needed.? So just
cut the reduction down to more like 1.8:1.? You'll be mainly operating in the lower
half of the 0A-200A motor current range, so not that hard on it or the controller.

There shouldn't be much inefficiency running the motor at less than 72V.? Possibly
they have a published spec for efficiency versus input voltage?? Too-low voltages
mostly suffer from needing more current and thus resistance goes up, unless you
go big on conductors (but inside the motor/controller are out of reach).? I would
think that 48V is pretty close to the sweet spot for the motor (if it even has one).

Here's my 10kWh 48V battery:

https://www.youtube.com/watch?v=fmk1_ynLdwI


Re: advice not on sailing boat

 

Dear Bobkart,
thanks again. I understand your reasoning on the 24v / 2:1 reducing IF full throttle is for cruising speed at 600 rpm.
But I want full throttle to be hull speed, say about 1100rpm.

so that would either be 48v with 2:1, or, 24v without gear reduction.

That brings me back to the questions, would this me1003 engine be terribly inefficient at 500-600 rpm ? ?Or what other parts influence the lower or higher voltage use (Peukert effect?)
I was finding the following numbers;

48 rpm per volt ? ? ? ? ? ? ? ?
RPM ? ? ? ? ? ? ? ? ?
450 slow 5 kmh 0,5 kw 9,375 volt 53,3 amp
600 rpm cruise 6,5 kmh 0,9 kw 12,5 volt 72,0 amp
975 reasonable fastest 9,5 kmh 2,85 kw 20,3 volt 140,3 amp
1050 theortaticly hull 10,5 kmh 3,85 kw 21,9 volt 176,0 amp

Thanks
elwin


Re: advice not on sailing boat

 

It does seem like you were experience more than 15% slip with the diesel.

Elwin's idea of just assuming you'll need a reduction and putting one in is a good one.? It doesn't look like direct drive will give you enough power (overpropped).

Keep in mind that lower prop RPM is usually more efficient.? I.e. the efficiency hit of a prop mostly comes from drag through the water, which goes up faster than linear.? Keep RPM lower and pitch on the high side and you'll win compared to less pitch and more RPM (generally).? The challenge with direct drive and your current motor is that your target prop speed of ~600mph is too low for your motor power-wise.? This is actually a general challenge for electric boat motors, and why axial-flux motors are brought into play.? If you end up needing a different motor, that'd be a good direction to consider (Lynch for example).

Once you have the ability to introduce nearly any reduction ratio you want to try, various combinations of battery voltage and reduction ratios can be experimented with.? If 4kW can hit hull speed, it sounds like 24V and 2:1 reduction seems close to ideal.

As a final consideration, you may be very close to being able to hit a decent cruising speed (~6km/h) at full throttle.? But, you usually want some headroom, and not run at maximum current 'all the time'.? Wind/current/heavy-load will be more difficult to handle if you're at max power just cruising.? So 24V / 2:1 seems like the obvious first thing to try.


Re: advice not on sailing boat

 

just to add,?

I remember from earlier research that a 4kw engine would probably be fine to bring the boat to hull speed. (10,5kmh, 1000/1100 rpm).

would that imply that 1200 watt would be enough for cruise speed?

I have trouble understanding the graph of the ME1002, but at 24v (rpm range would fit), would the efficiency then drop If on cruise speed (and is that a problem?)

?

Thanks


Re: advice not on sailing boat

 

Elwin,

My advice would be to not over think it. You are most likely going to need some kind of reduction gearing so set up a simple pully system using #50 motorcycle chain and sprockets which are very cheap and start with about a 2:1 or 3:1 reduction ratio and see what happens. Then you can easily change it with some different sprockets. The nice thing about chain and sprocket is it's easy and inexpensive to change up? Once you find the sweet spot you can switch to a synchronous belt drive if you want to reduce the noise or just put a shroud over the assembly and listen to it grind a little as you go down the canal.? That's what I did.??

The diesel on the Arc suffers from the same phenomenon that you are experiencing, that is, as soon as you put it in gear it wants to go faster than you like. For me it's about 3.5 mph at idle speed so when maneuvering in tight spaces when docking with the diesel the ship is lurching forwards and backwards and when you're dealing with a 20 ton boat surrounded by a million dollars in liability on all sides it give you a lot of pucker factor. It's also very hard on the transmission. The best thing about the electric drive is the rheostatic control of your speed. If you want to come in at .1 mph you can and adjust accordingly. Then all you have to worry about is wind and current.? Everything happens a lot slower and you know the first rule of mooring? is never approach a dock faster than you're prepare to run into at.?

With the smaller electric motor you will likely not reach the speeds you did with the diesel but you said that is not your goal anyway.

Nice little boat btw. Please show us some pictures of the engine and drive line too.?

Capt. Carter
www.shipofimagination.com?

On Sunday, July 23, 2023 at 04:34:39 PM EDT, <looije@...> wrote:


Thanks Bobkart,?
I only have references below on 'power consumption', so not really. This if what I measured with my old diesel engine. 340rpm is almost neutral. 9.3 kmh is not far from max speed.

rpmkmh
3403,5
5406,1
6006,5
8458,6
9759,3


S0 maybe there is more slip? I've added some photos of the boat.

You're suggesting a smaller prop, so I can make more rpm, so the engine will be efficient, right? if max rpm on 48v is 2250 (according to Monterey) then 24v will be 1125, right??
That's not that far off on the max rpm I expect I need with this prop.
If cruising on 50% of that max rpm @ 24v, is that a situation that needs to be improved??
by a smaller prop with direct drive
or
with the same prop with a 2:1 reduction at 48v??
is my thinking correct??

and what would be smart to do :-)
thanks again
elwin


i?


Re: advice not on sailing boat

 

Thanks Bobkart,?
I only have references below on 'power consumption', so not really. This if what I measured with my old diesel engine. 340rpm is almost neutral. 9.3 kmh is not far from max speed.

rpm kmh
340 3,5
540 6,1
600 6,5
845 8,6
975 9,3


S0 maybe there is more slip? I've added some photos of the boat.

You're suggesting a smaller prop, so I can make more rpm, so the engine will be efficient, right? if max rpm on 48v is 2250 (according to Monterey) then 24v will be 1125, right??
That's not that far off on the max rpm I expect I need with this prop.
If cruising on 50% of that max rpm @ 24v, is that a situation that needs to be improved??
by a smaller prop with direct drive
or
with the same prop with a 2:1 reduction at 48v??
is my thinking correct??

and what would be smart to do :-)
thanks again
elwin


i?


Re: advice not on sailing boat

 

600 RPM at 11-inch pitch will come to around 8.5mk/h (allowing 15% slip).

Unsure if your motor will have enough torque though.? Seems like it will only be putting out ~2kW at that RPM.

If you have a previous reference for power consumption at various speeds for your boat, that would help.

Thinking you want closer to 8" pitch, then you can bring RPM up somewhat, which will get more total power out of the motor.

Yes, prop efficiency will suffer somewhat, but without more torque from the motor, something has to give.

The above is all assuming direct drive to the prop.? A 2:1 reduction helps with the total power issue,
allowing use of 24V instead of just 12V.? Obvious downsides of more complexity, noise, and drivetrain losses.


Re: advice not on sailing boat

 
Edited

hi, last summer I started this post, now a bit further in the process - I've purchased a used set, the best I could afford now - knowing that I need to do some adjustments to make it fit my situation.

Can you share your thoughts on setting up my system? I like to keep most parts in tact, of course, but can imagine changing some elements may be the best option.?

what there is now;
an?16x11 inch prop?400 mm diameter , 290mm prop., there is room to fit a bigger one.?
my most used speed will be around 6,5kmh, around 500-700 rpm on the shaft?
good fit or replace?.

I bought a I think to powerful, but works 12-72v. As per their site, the ME1003 is designed to run 3000rpm at 72v, "This ME1003 is a Brush-Type, Permanent Magnet DC motor with very high efficiency. Capable of 11.5 KW continuous and 20 KW for 30 seconds (at 72 VDC). For voltages from 12 to 72 VDC input and 200 amps continuous (400 amps for 30 seconds ). "

I have 8 6volt 330ah batteries AGM

It may not be an ideal mix, but It's not a sailing boat, I just like to cruise the Amsterdam canals for a couple of hours.?
Need some power to manoeuvre when it's busy, and when crossing the river.?

I read a lot about higher efficiency at higher RPM, that would suggest reduction. But is that effluence difference significant?
would a direct connection to the ax be nicer, as it requires less rpm (less noise)?
Should I make this a 24 or 48 volt set-up?
(I'll probably want to change to Litium batteries when the AGM batteries I have die (in a couple of years?)).

How can I determine if I have enough power (torque?) in on 24vollt??
is cabling for lower voltage a significant costs compared to a higher voltage??

hope you can help me some pieces of this puzzle,
thanks!


Re: cruising Amsterdam Canals

 

hi all, i just bought the kit as described, got it for 2500 euros. let's see if it has been a good deal...

i hope you can give me some input to get me started.
What is missing is the forward/reverse switch. the Altrax controller needs an external f/r switch.?
I do have a throttle as one, it's called a wigwag throttle with a 3 pin connector, according to thunderstruck is works like this:

"A wigwag style throttle uses a potentiometer with 0-5K ohms resistance in one direction and 5K-10k in the other. It has a 3-wire connection to the controller, and requires controller programming before operation"

Any idea how can I can make this throttle work on the?
Alltrax SPM72400? the manual says a 400A current stock/hd switch suffices. the controller has a "ksi", "throttle 1" and "throttle 2" pin to connect?to the throttle.

or maybe better to get an different kind of throttle for this controller??

Thanks
Elwin


Re: cruising Amsterdam Canals

 

thanks!?

I was not afraid for the 1003 motor, glad to hear the Altrax will probably be fine too.?
The kit of motor and controller seem to be available new for about 1500 euros, battery charger about 800-1000 euros, any idea what I should budget if I would not go with thus used kit? for throttle, reverse, etc...
I'm wondering if 3500 euro ) would be a good price.
LiFePo from will be about 2000 euro for 48v 320ah, incl shipping and import taxes.?

Would be great to have your thoughts, going to see the set tomorrow.

thanks again!
elwin


Re: cruising Amsterdam Canals

 

开云体育

Twenty (20) years later and I’m still driving my boat with the ETEK brush motor I bought new in 2003.? I went thru 3 sets of brushes in that time (and no new sets were available until this past year!).? I cleaned up the armature a bit and have 3 new sets of brushes…sounds about as good that it ever did.

?

From: [email protected] [mailto:[email protected]] On Behalf Of Ryan Sweet
Sent: Friday, July 21, 2023 10:37 AM
To: [email protected]
Subject: Re: [electricboats] cruising Amsterdam Canals

?

Just to add to the chorus - don’t buy the used AGM batteries. Wait til you can afford LFP.?

?

As for the brushed motor : I’ve met plenty of folks with older diy electric setups with brushed motors from golf carts and fork lifts that are still going strong years later. I think it’s important to not ever go over the voltage rating of the motor as it will blow it out quickly. So if you can acquire the motor cheaply it’s likely worth a try. Even if your installation are is small I am guessing it’s still smaller than any diesel you remove, and so you have room to try it and later replace it if it doesn’t work out.?



On Jul 21, 2023, at 10:09, twowheelinguy via groups.io <twowheelinguy@...> wrote:

?

Elwin,

?

I've been using what is essentially a brushed, series wound golf cart motor on steroids in the Arc for over 12 years and thousands of miles and it's still going strong in the marine environment. While I've spent a lot of that time in fresh water rivers, I've also kept it in a salt water for quite a few years too. I have an Alltrax DCX-500 controller that's I've had a few minor issues with? but found the people at Alltrax very helpful so I would reach out to them for more info.

?

As for the AGM batteries, lead is dead, imo, unless you can get them thrown in for free I wouldn't bother with them. Don't know if you can get any of the Chinese LiFePo batteries over there but they are very reasonable and I've had good luck so far with several of the cheapest ones I could find. You can't hardly build your own for what they sell them on Amazon here in the states.?

?

Capt. Carter

?

On Thursday, July 20, 2023 at 09:39:21 AM EDT, Reuben Trane via groups.io <rjtrane@...> wrote:

?

?

I’ve been using Motenergy motors on Sunshine for several years - I have Sevcon controllers. You can reach out to Motenergy for support.?


the motor mount/reduction pulleys supplied by ?works well - mine gave a reduction of 3:1 to get max prop RPM to 800.?

You’d be better off building an LFP battery using Winston (or equivalent) cells if it’s in your budget.?


Re: cruising Amsterdam Canals

 

开云体育

Just to add to the chorus - don’t buy the used AGM batteries. Wait til you can afford LFP.?

As for the brushed motor : I’ve met plenty of folks with older diy electric setups with brushed motors from golf carts and fork lifts that are still going strong years later. I think it’s important to not ever go over the voltage rating of the motor as it will blow it out quickly. So if you can acquire the motor cheaply it’s likely worth a try. Even if your installation are is small I am guessing it’s still smaller than any diesel you remove, and so you have room to try it and later replace it if it doesn’t work out.?

On Jul 21, 2023, at 10:09, twowheelinguy via groups.io <twowheelinguy@...> wrote:

?
Elwin,

I've been using what is essentially a brushed, series wound golf cart motor on steroids in the Arc for over 12 years and thousands of miles and it's still going strong in the marine environment. While I've spent a lot of that time in fresh water rivers, I've also kept it in a salt water for quite a few years too. I have an Alltrax DCX-500 controller that's I've had a few minor issues with? but found the people at Alltrax very helpful so I would reach out to them for more info.

As for the AGM batteries, lead is dead, imo, unless you can get them thrown in for free I wouldn't bother with them. Don't know if you can get any of the Chinese LiFePo batteries over there but they are very reasonable and I've had good luck so far with several of the cheapest ones I could find. You can't hardly build your own for what they sell them on Amazon here in the states.?

Capt. Carter
www.shipofimagination.com

On Thursday, July 20, 2023 at 09:39:21 AM EDT, Reuben Trane via groups.io <rjtrane@...> wrote:


I’ve been using Motenergy motors on Sunshine for several years - I have Sevcon controllers. You can reach out to Motenergy for support.?


the motor mount/reduction pulleys supplied by ?works well - mine gave a reduction of 3:1 to get max prop RPM to 800.?

You’d be better off building an LFP battery using Winston (or equivalent) cells if it’s in your budget.?


Re: cruising Amsterdam Canals

 

Elwin,

I've been using what is essentially a brushed, series wound golf cart motor on steroids in the Arc for over 12 years and thousands of miles and it's still going strong in the marine environment. While I've spent a lot of that time in fresh water rivers, I've also kept it in a salt water for quite a few years too. I have an Alltrax DCX-500 controller that's I've had a few minor issues with? but found the people at Alltrax very helpful so I would reach out to them for more info.

As for the AGM batteries, lead is dead, imo, unless you can get them thrown in for free I wouldn't bother with them. Don't know if you can get any of the Chinese LiFePo batteries over there but they are very reasonable and I've had good luck so far with several of the cheapest ones I could find. You can't hardly build your own for what they sell them on Amazon here in the states.?

Capt. Carter
www.shipofimagination.com

On Thursday, July 20, 2023 at 09:39:21 AM EDT, Reuben Trane via groups.io <rjtrane@...> wrote:


I’ve been using Motenergy motors on Sunshine for several years - I have Sevcon controllers. You can reach out to Motenergy for support.?


the motor mount/reduction pulleys supplied by ?works well - mine gave a reduction of 3:1 to get max prop RPM to 800.?

You’d be better off building an LFP battery using Winston (or equivalent) cells if it’s in your budget.?