Sailboat Electric Outboard Motor Conversion - Cape Dory 27 Refit Part 4
Вставка
- Опубліковано 8 лют 2025
- We convert this Cape Dory 27 from inboard diesel engine to dual function outboard well that will hold either the Epropulsion Navy EVO 3.0 electric outboard or the Tohatsu 6hp Sailpro gas outboard. While we're at it we also replace the rotted core in the cockpit footwell. When the owner wants to make long coastal trips with frequent motoring he can use the gas motor. Otherwise he can swap it out for the electric motor which will be sufficient when he does not require more than 10-20 miles range (depending on boat speed). In practice we expect he can motor out of port, set sail, and if the boat speed under sail is close to 5 knots then he can recharge the battery using the motor prop for regeneration. If the battery is only partially depleted it could fully recharge on an overnight passage or it may take a couple days if fully discharged. Check the Cape Dory 27 playlist later for updates on the sea trials.
Annapolis Hybrid Marine epropulsion dealer
www.annapolishybridmarine.com
Pros and cons of electric inboard vs electric outboard motor:
With an electric inboard motor it may be difficult to find space for both motor and batteries without placing batteries in lockers that might be useful for other items, an inboard requires a higher sailing speed before regeneration kicks in, the prop and shaft is always exposed to fouling and damage and cause drag under sail at speeds too low for regen to begin and they are less efficient at transferring power from motor to prop. On the plus side, because it is lower and closer to the centerline, an inboard prop will not ventilate (lose thrust by sucking air from the surface) like an outboard can do in choppy waters. The electric outboard can be swapped out for a gas motor if you have a failure of the electronics or plan a long coastal or river trip that requires more range.
Advantages of gas outboard over diesel inboard:
1. Less cost up front and for future maintenance.
2. Less weight and wasted space.
3. Reduced complexity, which makes for easier future motor replacement or repairs. You can take the motor to the repair shop instead of bringing a mechanic and all his tools to the boat.
4. There is no fixed prop to snag fish traps and nets under sail.
5. If the prop ever gets fouled or damaged you just tilt it up and clear it or replace it by reaching over the transom.
6. Sailing performance is noticeably improved by less drag and turbulence once you remove the inboard’s fixed prop and seal off the prop aperture between keel and rudder. The rudder will also become more efficient.
7. You have the ability to swivel motor for side thrust when entering a tight marina slip.
8. An outboard well puts an end to inevitable diesel fuel and oil spilled into the bilge and their odors.
9. The self-contained outboard motor eliminates two more holes below the waterline-no engine cooling water seacock and plumbing or prop shaft in a leaky stuffing box.
10. Because you no longer need to access a diesel exhaust and prop shaft and all the rest, you can now seal off all the cockpit lockers from the bilge, giving you the added safety of collision bulkheads and less chance of flooding.
11. There is no need for a separate engine starting battery and charging circuit. This also makes conversion from lead acid batteries to lithium.
12. The motor does not radiate unwanted heat into the boat all night when you try to sleep in the summer or in the tropics after motoring.
13. A smaller motor has a smaller environmental impact.
14. Even if your electrics go dead you can pull start an outboard motor.
15. Outboard motors have less power loss than inboards, meaning that a 9.8hp outboard is closer in actual thrust output to a 15hp inboard engine.
16. You will become a better sailor by taking more care not to get in a situation where you rely on the inboard engine when you could use the sails instead. The more limited range and thrust of a small outboard teaches you to become a better sailor. You will find that as your sailing skills and experience in passage planning increase, there will come a corresponding decrease in the horsepower you need.
For more info on outboard well construction check:
atomvoyages.co...
We can be reached at atomvoyages.com or if you have a classic sailboat and want to share your experiences or have questions on fitting out, consider joining the Plastic Classic Forum at plasticclassic...
I'm a moderator on the forum and answer questions there.
Video editing by Benjamin Whiting. Check out his Cape Dory 30 YT channel - Aboard The Flying Spur:
/ @flyingspur
Very interesting to see the performance out come of this project. Any option a sailor has to get rid of that nasty oil dripping stinking extremely hot cast-iron beast is always a plus. Talk about redundancy what a plus to have the gas outboard on hand that you can just drop right down in its place
Great job as usual ! I love how you explain your thoughts and decisions . Your a very skilled person with the compassion to do everything the right way ... a true craftsman ! Thank you for sharing !
Thanks for this video. I have enjoyed your books and although have since sold my sailboat, I still enjoy seeing what you and May are up to. Hope you are happy and healthy and thanks again.
Excellent video - thank you sincerely for taking the time and care to document and explain. I learn from each of your videos and apply the knowledge one way or another to my boat (Farrier TrailerTri 720.) I have put a lot of thinking/designing into some kind of motor well that doesn't take up seat height. In my case I'd like to get the motor weight a bit less aft, maybe get it under cover/muffled. All the best!
Great work. I quite enjoy your innovation and seeing the stern section redesign. Thanks!!
Nice job of editing the different parts of the project seamlessly. Interesting project done with quality.
Cheers Warren
Just wonderful work. Always a pleasure to see your videos. Thank you.
What a beautiful transformation. Excellent design and workmanship.
Wowzers that's an amazing project an really exciting to see what's next for the vessel .. thanks for sharing your life and wisdom with us ✌🏼💗😊
Great audio track! I haven’t heard Dan in years..
lots of work done!!
This spring I'm going to fix my CD27's squishy cockpit sole, and use this video as a guide. I didn't catch if that piece of plywood below the sole was permanent or just a temporary support which you removed after the new core had cured. Many thanks.
It's permanent.
On a etap 23 w made a custom outboard well and torpedo makes a drive you can mount under boat and have battery inside with bluetooth throttle was pretty cool job
yes tyé dó
I love these videos and have for a couple of years now. Question.. When removing the inboard and going to the outboard, how does that change how she sits on her waterline?
In this case because the diesel was a small one weighting about 200lbs and located further forward than the outboard, the combined weight of outboard, solar, extra batteries and anchors tended to keep the trim about the same.
Outstanding work.
Beautiful workmanship. Thank you for sharing.
My question for you is how long did this project take in real time, surely not 22:48😊
The outboard well construction takes about 100 hours labor plus about 10 hours for the footwell recore.
As usual, great work James! I need to do two of those projects on my Triton, the footwell and filling in the hole where the prop was. The electric motor is a bridge too far for now. I’m wondering what kind of range you’ll get on the electric motor before you need another charge? I have a TORQUEEDO on my racing sailboat (Martin 241X) and I can get around 4 miles max, which is very disappointing especially considering how much I paid for it. I’m glad you’re testing another system! Look forward to hearing how it performs!
Hi James, beautiful work as usual. I have a question - do you ever use polyester Flowcoat on the internal parts of the hull and the bulkhead or just epoxy barrier layers + Bilgekote? In your experience is Bilgekote really as hardwearing as people make it out to be? (I've recently done interior of my lazerette with Interprotect (2 layers) and Bilgekote (2 coats) so I am curious.
Also, how is your experience using Cetol for exterior teak?
Cheers.
I don't often use a flowcoat, which is just gelcoat with 2% wax and styrene added to allow the surface to cure so it doesn't remain tacky, but maybe I should sometimes. It would be much better than Bilgecoat, which is a single part enamel of maybe polyurethane of some type. For lockers I often just apply two coats of white Interprotect 2000e epoxy barrier coat and leave it at that. No need to topcoat it unless you want a gloss finish for some reason. Cetol Natural Teak works better with less maintenance than other coatings I've used. In southern latitudes I've found it needs only one maintenance coat per year once you get an initial base on of three coats.
Thank you so much for your videos James! Could you please share battery model for Epropulsion Navy EVO 3.0 please?
It's the Epropulsion E80, a 80AH battery and their brand is required if you want to use it for hydrogeneration under sail. If one doesn't give you enough range you can put two in parallel. Later I'll upload an update on performance after sea trials.
Cancel
Reply
Fantastic work! A question about weight. I think you added 20 gallons of water up front (186lbs), in the back two outboards (Tohatsu 60lbs, EV 20lbs?) and 100 lb battery. How heavy was the desiel engine? Does the added weight up front change how the boat sails?
The diesel was about 200lbs plus another 250 or so for all the things connected to it (diesel tank, shaft, prop, linkages, 2 lead acid batteries, etc). We'll be putting back a similar amount in motors, batteries, solar, windvane, spare anchors, water jugs, and so on. Based on my experience on other similar boats and forward tanks such as my own 28-footer, the extra weight forward when the tank is full is only slightly noticeable in trim and sailing performance. And the owner always has the option to have a less than full tank and only filling it when his priority is water capacity.
Beautiful work. What kind of paint do you use on your interior projects? Does it hold up well?
I've been using EZ Cabincoat inside. It's a latex type single part and holds up reasonably well and is easy to recoat later. It only comes in white so I tint it off-white with a few drops of yellow and brown universal colorant. It's thin though and requires at least three coats. I like that it's mold resistant and semi-gloss or satin. Under it I use Pre-coat primer or for areas that have epoxy repairs, a two part primer such as Epoxy Primecoat. Others have reported that latex type porch and floor paints from places like Home Depot work good and cost less. If you want a paint that holds up better you'd need to use some type of poluurethane or enamel rather than water-based. But those generally come in gloss only and I don't like a gloss finish inside. I did try Brightsides with their flattening agent and that was a disaster because apparently the flattener attracted mold. For lockers and bilge areas I apply two coats of white Interprotect and nothing else.
The quality of the work is impressive. How long did it take to do this particular project?
About 6 weeks full time. It was slow because there were a lot of details to work out.
Nice jobs with the gas storage like that, what do you do for ventilation? Will that 6 hp and the electric get that boat to hull speed.
Thank you for sharing
When using the gas motor there is plenty of ventilation through the hull and transom slot and the small door on the forward side of the bulkhead. Based on using the same Tohatsu 6hp on my slightly larger 28' Pearson Triton, the gas motor will give us at least 5.7 knots full throttle in a calm with clean bottom. Later we'll test if the Navy 3.0 is truly equivalent to that or not.
Hi James, Great video. How is the rudder shaft sealed/supported in the cockpit sole?
The fiberglass rudder shaft tube is glassed to hull and underside of footwell sole. The glassing was shoddy where it went through the balsa core so I sealed that when I replaced the core with Divinycell which also added some strength to the joint.
Hopefully not too late for a response -- but your interiors always look very nicely painted. What kind of paint do you use? I need to do mine.
I don't like a high gloss pure white inside like Brightsides so I often have used EZ Cabin Coat which is a satin water-based, mold resistant interior paint for the main visible areas inside. The only problem is it goes on thin and needs 3-4 coats to cover and it only comes in white. To make an off-white I add a small amount of brown tint and a few drops of yellow. I've been told that the latex house paints called porch and floor from Home Depot is a good and cheaper alternative.
www.pettitpaint.com/media/5346/ez-cabincoat-product-data-sheet.pdf
@@atomvoyager thank you so much for the help!
You mentioned needing to grind away more paint to tab in those shelves. It looks like you didn't worry about getting every last little bit. Is that because grinding away the roving to remove all the paint would have removed too much thickness from the hull? If you had removed (I figure about half) enough of the roving to get all the paint, how many layers of 10oz cloth do you figure you'd need to replace it with to keep the original thickness?
I found the last bit of what looks like paint in that area was either a factory flowcoat gelcoat or epoxy primer well bonded to hull so didn't try to sand it all off. If I wanted it all off then it would not take more than about 15% of the hull thickness and that would need about 3 layers of 10oz or two of 1208 to replace. But since the shelves add strength in the same area, it's not so critical.
@@atomvoyager Thank you so much for the reply. I ask because I'm replacing bulkheads in my Cal 20 and I've found that getting the paint off completely requires grinding through about half the first layer of roving, so I chose to tab them in with three layers of 10oz without a taper. Again, thank you for the insight. Your videos are inspiring -- when I get frustrated with my project I watch yours and see just how much you can do to a boat if it's done properly and how nice it can turn out. :)
I think you could put the new thin, flexible solar panels over the top half of the entire hull. Lifeseal them on. Would be an interesting project on a relatively inexpensive boat.
I have actually seen (in person) solar on a hull, I’m surprised it is not more common.
I assume you're referring to the deck (or maybe the hull topsides above the waterline). I'd like to see details of how that's done and how to deal with all the wiring and waterproofing it. If anyone has links to a source for these panels and how they got installed I'd like to see it.
@@atomvoyager yes it was on the hull above the waterline on the bow, most of the light would have been reflected up on the vessel I saw. Ie. the panels were pointed towards the water more so than the sky. It was a trawler 30’ or so, pretty high freeboard at the bow
while watching these outboard well videos i've been wondering, why do you go for a shelf for gas cans instead of turning those same spaces into integral fuel tanks?
Because portable gas tanks are easy to remove for filling and cleaning and this gives you permanent buoyancy chambers with option to store something in them through the access plates or make easy inspections. An integral tank is complicated to build and make it leakproof with no chance of water ingress, they block access to the hull, would need to add fuel gauges, vents and so on. Having said that, it could be done if you needed it bad enough.
@@atomvoyager think you'll be offering diy patterns for the cd27 like you do with the triton's/alberg's? clearances were tight on the 6hp, and with the tiller location it's as far forward as it can go, could you have moved the mounting board aft/ modified the cutout to clear a 9.8?
@@clintcarter123 If someone wants the patterns and dimension sketches for the CD27 outboard well they can contact me through atomvoyages.com. There is not enough space between the transom and top of rudder shaft for a 9.8 hp motor on this boat. The Alberg 30 is the smallest boat I've seen that will hold a 9.8.
I look at this picture then at my boat with the black motor hanging off the back. Was this a result of your your thoughts while going around the globe. If so how excited were you to try it? Thanks
I've been building outboard wells on boats for over 20 years after struggling with a transom-mounted outboard on my own boat and it's been a great solution for like-minded sailors. About 12 years ago I came up with this workable tilt-up design. I've been waiting for the right opportunity to combine my outboard well design with electric propulsion and so far am happy with the results. We'll see how it goes after sea trials, but either way, we have the gas motor there as a tested good alternative.
@@atomvoyager when you do that does the outboard need to be an extended shaft?
@@redwood1957 Best result is with the 25" extra long shaft Sailpro model but the 20" long shaft will work in flat calm waters where the prop is not getting lifted out of the water to suck air in waves. The standard 15" short shaft dinghy motor doesn't work at all. I only recommend using extra-long.
@@atomvoyager have you ever done this on an Albin vega?
@@redwood1957 There's no space on the Vega available for an outboard well. Here's an overview article you should read: atomvoyages.com/articles/the-improved-outboard-well/
I was dreaming of this for several weeks and now you have episode on this :) would it work on albin vega?
The aft locker on the Vega is way too small for an outboard well so you'd need to hang whatever motor you wanted to use on an adjustable transom bracket. Not ideal though since it's exposed and difficult to reach.
Would a removable mainsheet track system like the ones from Barton work in lieu of the 3-point end-boom sheeting? I was looking through their catalog today and that popped out at me.
I suppose it could be made to work though it looks like it would interfere with the tiller at least so you'd have to remove it frequently. I think I'd prefer the 3 point end of boom sheeting though since it's more out of the way and works well enough. www.bartonmarine.com/products-removable-mainsheet-systems.asp
№ 444😀
Pick one or the other 🤦🏻♂️
Agreed. It's a hassle to swap motors frequently and to carry two aboard. For the owner it's an experiment in EP. He thinks his cruising style will suit the short range motoring mixed with long offshore legs giving ample regen time so that's his initial plan. We'll see how that works out. The problem with EP is range and reliability of complex electronics. If he decides next year to transit the Panama Canal or do the ICW to the Great Lakes he can use the gas motor. If the 48v system has a failure, he has the gas option until it's convenient to make repairs. With both motors he's covered for any situation and we get to make a real world comparison to see if the Navy 3.0 thrust is truly 6hp gas equivalent. If it works well then I can use that gas motor on one of our other boats. And a future owner of this CD27 can make his own choice.
@@atomvoyager I appreciate your work and your channel, this one just seemed silly.
I agonized for ages over whether to go electric or get a new diesel and on my second day out after putting in the new engine a 90 minute motoring session stood between sleeping at anchor that night or staying awake all night. No regrets 😆
Good point. EP with limited range certainly steps up the challenge of sailing for better or worse. With EP there's more incentive to become a better sailor but it comes at a cost.
biy éltriç