Left turn Clide. Going Hybrid?

[StarChaser]

Das Boat 2-9.0L Internationals with ~3200 Hrs on them in an '82 Carver 3607. I really love the layout. 2 cabins (fore & Master Aft), 2 heads, down galley, Engines & Salon midships, Upper & lower bridges, etc. But Star is in need of some major work. She is 38, & I'm her 6th owner with all of the issues associated with poor boat ownership & maintenance. I got her 5 years ago.

I got some not so pleasant news preCovid lockout. I knew my starboard engine was in trouble. Bad fuel caused the injectors to fail on both engines. The injectors failing caused fuel to be dumped into the oil (it blew past the rings). She also took on 18" of water because of the bad fuel causing the wet-exhaust hoses to melt and flood the bilge. All not good. The Port engine needed 1 injector and several oil changes to be back up & running ok. The starboard engine had 4 injectors replaced but burned the alternator and starter trying to get it back up & running. It'll turn but won't run. I'm considering it dead until I get her to Baltimore for a better look. The compression seemed to be ok but.... Now Ive found out that there is scoring in the starboard engine. So since she's still in North Carolina and I'm in Baltimore working on her is a problem. The plan is to bring her back on the port engine after the Covid mess is resolved, and get to work. Fortunately my grand-nephew is a marine diesel mechanic so I'm fairly certain I can get some help there.


I can't dump her, I'll never be able to get another boat, SWMBO & finances will prevent it. I have to fix her.


My thought is that IF the Starboard engine is trashed, then remove both engines and replace with a diesel/electric hybrid system.

Thoughts? Suggestions?



Thanx

 

[Pete Meisinger]

You can't afford it.

On the bright side if you are handy and your grand-nephew is willing to help, you should be able to get that Starboard engine up and running by pulling the head and honing the cylinders.

The reason that starboard engine will not start is fuel and injector related. Don't try to start it anymore until you pull the top and check the cylinder walls and redo all the related injection problems It shouldn't be an awful job and not too expensive. Depending on how much you are able to do yourself you might get by for less than $5,000.

By the way. Pull the prop on the starboard engine before you attempt a 500 or more trip on one engine. With the one prop gone you will have a nice trip at trawler speeds and probably not notice one engine is just along for the ride.

pete

 

[RT Firefly]

Greetings,
Mr. SC. Bad news indeed. Our Mr. FF has mentioned several times that school bus diesel engines are quite affordable. I have no idea if the 9.0 liter International was ever put in a school bus but you have all the marine parts on the possibly dead engine. Might be a cheap swap without all the intricacies of a hybrid design and install.
Ask your grand-nephew. He should know the options and possible costs.
You would, after all, only have to replace ONE engine.



Careful on your delivery trip. Get tow insurance and watch the weather.

 

[mcarthur]

Depends on what type of boating you do, where, conditions and how fast you go...

Keep the port motor, replace the starboard with a direct-to-shaft electric. A decent battery bank (not too big), and a honking big alternator off the diesel.
Speed low (electric only) - electric only off batteries for a time, then …
Speed low (dual) - diesel in gear just above idle and use the alternator juice to power the electric engine (beware too long in this mode for diesel)
Speed med - same as dual, but can go for a long time
Speed high - same as dual

You'll not get the same high speed as with two diesels, but you may have been over-powered anyway (2 x 165hp, but they may not have been getting that anymore anyway) - did you have to run them full power to get the speed you want? If so, are willing to cut top speed a little?

Against a 1x165hp international, you could think of a 8-12kW electric. It could soak up the unused diesel at near idle nicely with a big 5-6kW alternator. If you had a genset that could be used instead. May get you 4-5kn on electric only, 6 in dual mode. Since your max is about 8kn that would be quite nice...

Cost would possibly be US$3-4k for alternator, US$3-4k for motor (thunderstruck), US$6-10k for battery pack, then install costs + sundries like dc-dc charger.

Then your maintenance halves, your quiet enjoyment under electric improves out of sight, you lose a little top speed and have lots of electricity available (if you use the pack as house bank too). BUT it's a bit costly and you may use much more rudder to offset the port-stbd difference in power, or running electric only - I don't know your boat!

 

[Comodave]

Years ago PMM had an article about diesel over electric and how it was going to take over the market. It was very seductive but it never went anywhere. I would be very wary of trying anything like that. You could get into a rathole spending money on something that may never work or work well. And the costs will eventually be way more than you could imagine. Rebuild the engine you have will be the cheapest way to go, or swap it for the same engine if you can get the old one out and the new one in easily.

 

[Benthic2]

Sinking that much money to design and build a brand new system in a boat that old, which, even if you get it all working, will have zero resale, really isn't practical.

Switching to 2 rebuilt gassers might be a cheaper option.....and then you'd have a boat that is worth about $20-30k.( based on a quick review of yachtworld )

Here's one for $15,000

https://www.yachtworld.com/boats/1985/carver-3607-aft-cabin-motoryacht-3533693/

 

[FF]

Different engines need not be that expensive.

If you can do the work smaller gassers would work.

Or if you just want a vacation cottage , pull the engines (or pickle them for the next owner) and put a 40HP outboard on the stern.

 

[JD Ray]

I'm in mcarthur's camp. I've been researching electric drive systems for boats for a while, and the biggest cost is in batteries. The amount of battery you have will determine how far you can go on straight electric, and if you're running a genset to drive your electric motor all the time, you might as well save a little energy conversion cost and go straight to the prop shaft.

You're going to want a liquid-cooled motor. I'm not familiar with the Thunderstruck motor that mcarthur suggested, but this Siemens is the one I think I'd use: https://www.evwest.com/catalog/prod...ucts_id=257&osCsid=6526ib59qv8oq1egrcvq57sla4

Batteries can be had for as little as $130 per kWh. If, per mcarthur's suggestion, you can cruise at 12 kW of motor, then (nominally) 12 kWh of battery pack will get you however far you get in that hour (six nm?). So figure 1/2 mile per kWh. If you normally cruise 100 nm in a trip, then you need 200 kWh of battery to avoid using the genset. At the cheapest, you're looking at $26,000 in batteries, then about another $10,000 in motor, inverter (which is expensive), charger (also expensive), controller, and other sundries. I have no idea how much labor for installation would be, but if you don't know how to do it yourself, plan a few thousand at least.

The batteries in question are these: https://www.evwest.com/catalog/prod...ucts_id=486&osCsid=6526ib59qv8oq1egrcvq57sla4 They're designed for a ten year life of daily discharge, which ought to carry the average cruiser for quite a while.

Those motors stack linearly, by the way, so if you want more power than one provides (unlikely given your current engine size), add a second motor. Alternately, once you get all the infrastructure in place, get rid of the other diesel engine and replace it with a second motor, because the same battery bank will feed both motors, and the same genset charges the batteries... Well, you get the point.

Frankly, I think your boat probably isn't worth the ~$50K worth of infrastructure and labor it would take to migrate this way. The same setup would do a similar migration for a newer, nicer hull. BTW, I agree with you that the 3607 has a great layout. If I found on in in the PNW, it would be on my list of things to consider.

Best of luck.

JD

 

[stubones99]

Oceanvolt makes some pod drives / sail drives that are electric and I think the whole system as well...
As most have stated before, it will exceed the value of your vessel.

 

[Comodave]

You may like the idea, but I doubt that anyone else looking for a boat to buy will. You will kill the resale value of the boat.

 

[High Wire]

>>>She also took on 18" of water because of the bad fuel causing the wet-exhaust hoses to melt and flood the bilge.


I'm confused by the bad fuel/melted exhaust tie. That does not compute.

Fix the originals or replace the engines with reman Cummins B series.

Forget the hybrid unless you are a retired electrical engineer looking to keep yourself busy for a few years. Everything will need to be custom made. After you are done, no one will want to buy it.

 

[GH41]

I found myself interested in a 34 PDQ powercat with tired engines. It looked like the perfect candidate for an electric conversion. No way I could get the math to work.

 

[OldDan1943]

Personally, I think it is too early in the diesel electric conversion tech.
Bite the bullet and rebuild what you have.
You did bleed the injectors????

 

[stubones99]

According to this guy, it can be done... but it costs $$$

and

 

[JD Ray]

Per the recommendation of someone on this board, I've been reading "Voyaging Under Power, 4th Edition" by Bebe, et al. Just last night I read that a catamaran has an S/L ratio of "3.25 or more". Compare this to a full-displacement hull S/L of 1.34.

How is this useful to know? Take the LWL of the 34 PDQ (33' 11", surprisingly enough) and find it's square root (~5.8). Then multiply that by 3.25 to get the hull speed in knots (18.85). Compare that to a boat with a normal displacement hull with and LWL of 34', perhaps an LOA of 38', which would have a hull speed of 7.77 knots at the standard 1.34 ratio. So, for a given displacement, the cat should go twice as fast for the same amount of power applied. I think.

The problem with electric conversions right now is the price of batteries. I think catamarans are the only viable conversion right now unless you have money to burn. But that PDQ 34 would be a great candidate. Two liquid-cooled motors like I linked to above will be way more power than you need, but you don't have to use it all, and they're not terribly expensive given the overall package. Figure $15K plus batteries. Using the batteries above, target another $5K on batteries and end up with 40 kWh. That should give you four hours or more of leisurely cruising without kicking on a genset.

Now you've got me wanting to shop for a PDQ 34...

 

[OldDan1943]

Now you've got me wanting to shop for a PDQ 34...

Yea, I thought the PDQ was a neat design. IMO everything was convenient except the head. Well, we were in one of the hulls, I turned around, my 'then' wife's eyes were big as bucket bottoms.... She was NOT comfortable so we quickly left the boat.

You can still the USED PDQs
Good hunting.

 

[JD Ray]

I hunted some. For that kind of money, I'll buy something else.

 

[OldDan1943]

I hunted some. For that kind of money, I'll buy something else.

The down side of the PDQ is, the beam is 16ft so that generally means, in my case, I would need to consider something longer than 55ft X something wider of 15 feet. This is the traditional measurements of the slips at Waterways Marina

 

[StarChaser]

McArthur,

Yes, Star is overpowered for the way I drive, (ICW, cruising. She's NOT a go fast boat.), on the other hand being able to crank those puppies up & do 20 Knts something I like having in my backpocket if I need it (i.e. Out running a storm comes to mind), but I would be willing to give up some of my top end. Say maxed out at 15knts. Right now she idles along on the port engine at 5-7knts, cruises at 2200RPM 9-10 knts, max is 12 for SHORT bursts. No prop on the Starboard shaft.



Benthic2


She probably will not be worth what I put into her. SWMBO (aka The Admiral) very probably will not allow another boat. I got Star because she was less expensive than an apartment and she thought we would sell her to help finance a house in Florida. A Job change caused another job change from Tampa Bay to Baltimore. I tried to do a short quick sale on Star but that didn't happen. So my son & I tried to move Star from Tampa Bay to Baltimore via the ICW. As a result I have to either fix her or scrap her and stay ashore, permanently. I'm keeping my boat!



No Gassers, Diesel or Electric only





JD Ray,

Agreed the batteries are the biggest cost followed by a large enough solar array to have a good charge return rate. I have a 20Kw solar panel on my home. (The home will become a rental property when I retire in 7 years) I will install that panel over the Flybridge. That'll give me a bimini and charging array.

The batteries are the thing I'm concerned with. I don't know how much I'll need to cruise with. The Longest run I made was 11 hours @ 12 knts. I can't say how far I went because I got caught in a storm and simply circled an island that my son & I were staying at. I know we were beat to crap when we docked again (Lady's Island Marina; Nice folx, let us stay an extra day to recuperate , no charge). NOAA report said 1-2ft waves & 5-10 knt winds, we got 6-8ft waves & 30-40knt winds. Not a fun day on the water.


Comodave,



I'm not interested in resale, Star is my last boat. My ids can inherit her in 20-30 years when I'm done.





High Wire,


Internationals 9.L are very durable engines (they used them in School buses so they can take abuse). The fuel was contaminated by river water. enough to overwhelm my Racors. ~26 Gal out of 160 Gal. The engine had enough fuel to keep running even with the water. The water turned to steam in the exhaust and melted the rubber hose where it connected to the riser on the inboard side of the engines. Why the inboard side only I couldn't tell you, but it made a 3-4in hole in both hoses. Those holes allowed the fresh water to be pumped into the bilge instead of going out the stern. It didn't take long to do. I have a 2in fresh water intakes for each engine. That a lot of water coming in quickly.



Not and electrical engineer, just a Master Electrician/Electronics Technician/ Journeymen Cabinet maker/ Journeymen plumber/ JOAT



Old Dan1943,

Yes, Both engines had the injectors replaced and the injector pumps rebuilt. The Old injectors have been rebuilt & are aboard as spares. Everything was bled, and should be working in the Starboard engine, but it isn't. The Port engine ran after the replacement & bleeding, but the starter motor on the Starboard engine failed. It has been rebuilt and will turn the engine but it will not run. I'm being conservative and calling it dead until I know it can be saved or is dead. I know that I don't know enough to be able to tell one way or the other. My grand-nephew does that for a living. I'll let a pro look at it. I'm trading a garage rewire for his labor, totally worth it IMO. If the Starboard engine can be fixed, then game over I'm keeping the Internationals and calling it good. Do the rewire, replumb, add propane, and replace the flooring and call it a done deal.

Oh yeah & figure out why the freeak the Genny won't run unless I'm underway!?!





JD Ray,
That's what I was looking for. Figure $30k minus the resale on the good Port engine and the Westerbeke $5k(?) total return, that makes the budget for a conversion 25k plus the batteries. That may actually be doable. I refurbish Hybrid batteries as a side job.



PDQ's sound good but, I have 2 good solid shafts, 22x22 props, struts, etc. I like/love the way Star handles with her twins.



I plan on a complete overhaul once Star is here in Baltimore. I don't trust the wiring after the water bath and it's 38yrs old & had 6 other people chopping on it. I did remove a small shoebox full of wirenuts before I ever castoff. I've made arrangements with the yard to allow me to have a half size shipping container for my tools, supplies, & materials that I'll need.



John

 

[JD Ray]

OK, I am in full support of this project (which, with two dollars, will get you a cup of mediocre coffee). BTW, I just looked at the layout on that boat. For the price you can buy one, it's a perfect-looking boat for our initial needs. Of course, you apparently can't get one on the West Coast (initial search only). On the way, however, I found this neat site: https://boatgraph.com/ I'm going to fool with it a bit and see what I come up with.

PM me and keep me up to date on your project. I'll do research for you if it will help.

Cheers.

JD

 

[rslifkin]

Worst case, if that engine is actually shot and you don't want to swap to different engines, it's probably possible to find another 9 liter out of an 80s International truck or bus and swap it. Might need to swap the injection pump and injectors from yours though, as I think the truck ones were rated a bit lower than the marine versions.

The diesel / electric idea is a cool one, and I personally like the idea. But in this size boat, I don't think we've reached the point where it's practical yet.

 

[StarChaser]

JD Ray,



I don't think many Carvers made to the West Coast. I know mine stayed with 300 miles of St Pete for her entire life until I got her. She only had 2200Hrs on her engines & 600 on the Genny, I have the Original owners log books and manuals (right down to the bill of sale) & have spoken to him. He loved Star Chaser (her original name) but age & health forced him ashore. The next 4 owners were of decreasing levels of care & competence. Star is now mine & my child, I will fix her & pass her on to my kids (probably my daughter). When I retire in 7 Yrs I plan on doing the Loop, the Bahamas, & the Caribbean. If I come shore again it'll be because I have no other choice.

 

[ScottC]

You might want to check on the insurance (premium and liability) impact of such a project. I am a firm believer in Diesel/Electric hybrid, as I have owned such a boat for 10 years...BUT there is a higher risk for battery/electric-related fire than for a basic diesel installation.



Furthermore, you should expect to go through a LOT of extra learning, as hybrid installations can be complex...and they typically involve computer components. Be prepared to do a lot of your own troubleshooting if you plan on extensive cruising, as yard knowledge is still sparse.

 

[JD Ray]

I just spotted this on the Greenline Yachts site describing the Greenline 48 Coupe:

Hybrid Drive is available with 2 x 14 kW electric engines... (snip) ...
Running on electric power, the 48 Coupe is cruising at 6 kts and with the range of about 20 NM with the 40 kWh Li-Po battery.

Based on the idea that eight hours of cruising is about all most people want to do in a day, then ... (counts on fingers and toes) ... 96 kWh of battery, or eighteen Tesla battery packs at 5.3 kWh each ($1580) would do that. Figure $28,440 for batteries, $2800 for a motor, $6240 for a controller (yeesh!), and a few thousand for the other bits and bobs that make up the system, it seems like $40K would make a decent budget for a project like this, genset notwithstanding.

 

[JD Ray]

I did a little looking at the Greenline 33 and 39. The brochure for the former shows a 50 kW power draw at 11 knots, and a range of 25 nm at 7 knots on 40 kWh of battery. The latter shows the same draw at 11 knots, and a 50 nm range on 80 kWh of battery at 7 knots. I suspect these numbers are rounded, because they indicate an identical under-way performance. I suppose it could be the case given the longer LWL but larger displacement of the 39.

Maybe.

So, at 7 knots, the 39's 80 kWh gets us 50 nm. That's 7.14 hours of cruising at that speed. The 33's 40 kWh gets us 25 miles, so that's 5.71 hours of cruising at that speed. 80 kWh divided by 7.14 hours is 11.2 kilowatts for seven nautical miles across an hour, or 1.6 nm/kWh of banked power. I think. 40 kWh divided by 5.71 hours for 7 nm across an hour makes for 1.0 nm/kWh of banked power. Someone please check my math, but this makes a certain amount of sense to me due to the (presumably) better S/L ratio of the 39 (Greenline doesn't provide the LWL of either boat that I can find).

Let's presume that the truth is somewhere in the middle, and 1.3 kWh/nm is a good off-the-cuff estimate for a yacht of about this size. If you want the ability to cruise eight hours at seven knots (56 nm) without running the generator, then 72.8 kWh of battery is needed, or about fourteen of the aforementioned Tesla batteries ($22,120; slightly lower than my previous estimate).

The great part is that at 1.3 kWh/nm, that's a shade over 9 kW of genset to cruise as long as your fuel holds out. A 12 kW genset at 3/4 throttle burns ~0.71 gallons per hour, or about 0.1 gallons per nm. Again, someone check my math, because 10 mpg seems like a hell of a reason to convert to hybrid electric. That can't be right. Can it?

 

[DDW]

There is no way the hybrid part of that makes it more efficient. You must convert the diesel to electricity, then the electricity to torque for the prop. Each conversion costs efficiency (probably around 20% in this case). If the genset motor is enough to power the boat then couple it to the prop and be done with it. For long range cruising, hybrid will never be as efficient as directly driven, unless there is some other source of energy (like seawater ). A hybrid has other advantages for some uses, short trips from dock to dock where power is available as an example.

The Greenline hull may be particularly efficient, but it has nothing to do with it being hybrid drive.

 

[StarChaser]

JDRay,

Your math makes sense to me. A couple of questions though.

Do you plan on any charging along the way with Solar, Wind or by Genset?

What kind of batteries are you planning on using?
What will be your source?


My plan is to (IF I have to) convert to a series hybrid system with a 20KW solar panel (Repurposed from my house) for primary recharging, and a 30Kw diesel Genset (also repurposed from my house). The recharging systems will recharge the Lithium Ion batteries (Salvaged from Leaf, Civic, Prius).

 

[JD Ray]

There is no way the hybrid part of that makes it more efficient. ...
The Greenline hull may be particularly efficient, but it has nothing to do with it being hybrid drive.

I’m certain I’m wrong somewhere along the way, or that it won’t come out that well. But I want to know where it’s wrong. It doesn’t make sense.

 

[JD Ray]

JDRay,

Your math makes sense to me. A couple of questions though.

Do you plan on any charging along the way with Solar, Wind or by Genset?

What kind of batteries are you planning on using?
What will be your source?


My plan is to (IF I have to) convert to a series hybrid system with a 20KW solar panel (Repurposed from my house) for primary recharging, and a 30Kw diesel Genset (also repurposed from my house). The recharging systems will recharge the Lithium Ion batteries (Salvaged from Leaf, Civic, Prius).

There’s no way you have room on a boat roof for a 20 kW solar system. 2 kW if you’re crafty. On the 30 kW genset (or “gender” as autocorrect puts it), is the one you have designed for marine use? If not, exhaust and cooling issues will bite you. Maybe sell it and buy a marine genset. The batteries I identified are Tesla packs, which you can find online (evwest.com, etc).

 

[twistedtree]

I’m certain I’m wrong somewhere along the way, or that it won’t come out that well. But I want to know where it’s wrong. It doesn’t make sense.

At least one math error is the in the beginning of the second paragraph. The 33 will cruise for 25 nm/ 7nmph for 3.6hrs, not 5.7hrs. That throws things off later on.


A hybrid boat is mostly good marketing, and mostly bad engineering. If you were going to use a Greenline strictly as a day boat over short distances, and strictly at a slow 7 kts cruise, it might make for a nice lifestyle boat choice. You could impress some of your friends with your thoughtful and forward thinking boat selection, and embarrass yourself in front of other friends who understand the physics involved. But if it makes you happy, that's what really matters.


I think in practice, round trip range is probably about half of the published range. Like most builders, the published numbers are very optimistic, and seldom hold up in real life. For example, they quote the boat at 4800kg empty, and based on prop calculators that requires 12.7kw to move 7kts, not 11.2kw. And that's for an empty boat. Add in 500kg of gear, water, etc, and the power requirement goes up to 14kw. Add in another 300kg of passengers, even attractive thin and fit passengers like in the brochure, and the power requirement goes up to 14.8kw. Then plan on using no more than 75% of you battery capacity for your planned route. So the 80kw battery becomes 60kw usable, and you now have 4hrs of cruise time and a 28nm range. And I'd probably use 50% as a safer range to allow for fighting current, seas, and wind. Now in fairness, this is probably a good match for a lot of boaters, but probably not for typical trawler use.


Also keep in mind recharge. Once home, you need to recharge. Now I'm assuming you are running this as an electric boat because you really value quiet running. If you are running it as a hybrid, then I really don't understand at all what benefit you are getting, but that's a separate topic. Anyway, you get back to your slip and plug in. If you have a 50A/240V shore power connection, that produces 12kw when running at full capacity. It will take about 7hrs running at full tilt to recharge, and most people would cringe at the thought of running a shore power connection at full power continuously. So let's assume you cna throttle is down to say 75% power, you are now up to about 9hrs of charge time. Again, this might be fine for your usage pattern, but understand that it will be giving your shore power a real workout.