electric engine - rainwater in bilge

[elooije]

Dear members,
I've read a lot of interesting topics on this forum about replacing a Diesel engine with an electric one.
I have an open boat that I like to do the same, I'm just worried about the water in the bilge that will always be there. I'm afraid the air will be moist, warm when in operation - any reason to worry?

it's for a 1912 steel old rescue boat, 5,5m/18ft. it will just cruise the Amsterdam city canals and an occasional trip along the picturesque lake and rivers nearby.

The Thunderstruck conversion kit, using the Motenergy ME1115 engine looks very interesting, but will it be good fit for an open boat like mine?

[tkeithlu]

Welcome to the forum, elooije.

Hmmm. I participate in the maintenance and restoration of a boat that came into the family second hand in 1909. One of our assumptions is that we keep the boat as close to its 1930 format as we can. That's damned expensive; overhauling the rudder on a 20 ft boat cost me 1,000 pounds a few years ago.

So, how interested are you in 1912? The electric system would be quiet, likely have all the range you need, and not be difficult to shelter. You are bound to be including enough batteries to keep the bilge pumps ahead of the game. But, it is a radical revision from the earlier state.

As I understand it, you are keeping the boat in fresh water, and the risk is rain accumulating in the bilge and flooding the electric motor. The batteries, which are also going to be low in the boat, are as much a problem.

I would start with canvas to cover the whole boat, neatly and completely. Then I think I'd rig a second bilge pump with a separate battery that can sit on a thwart while the boat is in storage.

How is she docked? Any chance of a boat house? Trailer or hoist so that you can pull the plug?

[seandepagnier]

the problem is the inboard which is not a very good way to power a boat with an electric motor

[elooije]

thanks for your thoughts;

the boat has to be electrified in order to be allowed to cruise the amsterdam canals, the government will ban diesel or petrol engines from 2025.
the engine that is in the boat now isn't from 1912 anyways, so no historic loss there.

I do like the suggestion to have a 2nd bilge pump on a different battery, that is a smart safety for not that much extra cost.

I am not afraid the engine or batteries get wet or get flooded - but I am worries about the damp/moist from the few centimetres of water in the bilge at all times. This may get moist/humid especially when the engine is using that air for ventilation.

So, how well does an electric engine work in such an environment?
are there waterproof engines, IP rated?
or no reasons to worry?

thanks!

[tkeithlu]

I don't think that it will be a problem. Anyone in Florida lives in a more hostile environment for electric motors, and we're doing OK.

[Statistical]

You may want to lean towards motors that are classified as:
Air Cooled, Totally Enclosed motor
or
Water Cooled, Totally Enclosed motor

Air cooled is likely fine for your power requirements and will be cheaper and easier to implement. Total Enclosed is the important part. You probably don't need a waterproof motor those are motors designed to be submerged a TEM is a step below that and should be fine.

The motor you are looking at is a fan cooled open motor which means it pushes air into the internals of the motor where the stator and rotor with all those copper windings. In a sea water environment that would be very bad choice. Not sure about freshwater but I given the number of TEM (totally enclosed motors) out there I would lean towards that for any damp environment.

[Dsanduril]

While Statistical is right about the overall construction and totally enclosed would likely be more resilient, the alternators that sit on nearly every engine on all of our boats are really just fan-cooled open motors. In my engine room they we the first thing to show signs of rust/corrosion, but at the same time they give a decade or two of service just fine. Is that a long-enough life before a rebuild (almost all the materials inside are re-buildable or fully recyclable) or do you need a longer design life?

[flyingfin]

Visit a motor shop that repairs wastewater pumps and ask about a new or rebuilt wastewater pump motor. Those are electric motors, that normally sit submerged in raw wastewater for cooling.

You can buy one of these electric motors with a jacket for cooling without submergence in water (dry installation)

The jacket can be filled with oil, or fitted with inlet and outlet for raw water cooling and overboard discharge using your existing vessel raw water & exhaust thru hulls.

[elooije]

thanks for these helpful thoughts,
I will look try looking for Totally Enclosed motors - any other brands suggestions then Motenergy?


I look into the wastewater pumps as will, that is a nice thought. though I don't know if I then run into different problems how to control such an engine...?

[Statistical]

Originally Posted by elooije

thanks for these helpful thoughts,
I will look try looking for Totally Enclosed motors - any other brands suggestions then Motenergy?


I look into the wastewater pumps as will, that is a nice thought. though I don't know if I then run into different problems how to control such an engine...?

For DIY (and I assume you want to go DIY not a turnkey solution due to cost) Motenergy has a good reputation with EV hobbyists. They also make TEMs. There is also HPEVS but they tend to make larger motors with more output than you may want or need.

The Motenergy ME1718 is a 100a BLDC and ME1507 is a 160a PMSM. I assume you are going to be running at 48V? That would get you 4.8 KW or 7.68 KW continuous respectively.

BLDC or PMSM (AC) doesn't really matter. Both are going to use a controller to convert your battery DC to what the motors needs.

Make sure you buy from a hobbyist site that can help you with programming the controller. Controller programming is far from new user friendly.

Also as Dsanduril says marine alternators are essentially fan cooled open motors (working in reverse) and they seem to last so a TEM might not be needed.

[ranger58sb]

Maybe you can eliminate water from the bilge. Dripless shaft seals. Re-caulk fittings, deck-to-hull joint, etc. There's a system called "Dry Bilge" or some such that sucks out water a normal bilge pump can't get. Plumb, or re-plumb, cockpit scuppers.

Et cetera.

-Chris

[Sailmonkey]

Originally Posted by ranger42c

Maybe you can eliminate water from the bilge. Dripless shaft seals. Re-caulk fittings, deck-to-hull joint, etc. There's a system called "Dry Bilge" or some such that sucks out water a normal bilge pump can't get. Plumb, or re-plumb, cockpit scuppers.

Et cetera.

-Chris

Ummmmm......it’s an open boat.

[ranger58sb]

Yep, got that. Aside from occasional rain and maybe some occasional spray, that doesn't mean to me that water in the bilge is mandatory.

And if it's an "open boat" but has a hull liner, maybe even more controllable.

-Chris

[elooije]

thanks but the water is kinda unavoidable, so that's why I was wondering what the effect would be on an electric engine.
I don't think any pump will that that last 1cm out of the boat.

[ranger58sb]

Originally Posted by elooije

I don't think any pump will that that last 1cm out of the boat.

Yeah, there is one. Search "Dry Bilge" -- a system meant to augment a traditional bilge pump system. May be other brands, too...

-Chris