If You Were Repowering...

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menzies

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May 11, 2014
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SONAS
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Grand Alaskan 53
So if you are told that a rich uncle had died and left you enough money to repower your boat with anything you wanted, single or twins, what would you repower with and why?

The will stipulated that you MUST use the money to repower your existing boat, not use it for any other reason, otherwise you did not get the money.

Would you upgrade your existing with new of the same, go with something else, totally redesign your ER structurally and change from one to two or vice versa.

What, and why?
 
Greetings,
Mr. m. What an interesting question. Hmmmm... Currently have twin 120 Lehmans and weigh about 25t. Go to a single ? With single prop or run twin props? Smaller twins? Originally we were looking for a single but ended up with twins because our particular boat was never offered with a single and I sort of like the reliability/redundancy/maneuverability although I don't find too much added expense with the twins and the scantlings are such that she is NOT a blue water boat. So, added range (currently ~1200 nm I think) would be somewhat wasted.

This is a similar question to the "which boat would you buy if your rich uncle..." The answer to THAT question was/would be, same boat but a factory rebuild to as new.

Like to hear what others have to say before I commit....
 
I'm afraid I'd have to donate all of it to my favorite charity because I now have Cat 3406C's and love 'em. They're turbocharged and turn out 580hp each and push the boat at 31.5kts if I want yet will idle along all day long at 8kts.


I can't think of an engine I'd rather have.
 
120hp 480v 3 phase electric motor, VFD, generator, inverter and battery bank.
 
I'm afraid I'd have to donate all of it to my favorite charity because I now have Cat 3406C's and love 'em. They're turbocharged and turn out 580hp each and push the boat at 31.5kts if I want yet will idle along all day long at 8kts.


I can't think of an engine I'd rather have.

Then you would not be donating as you would not get the money.
 
120hp 480v 3 phase electric motor, VFD, generator, inverter and battery bank.
Interesting thought. Ships and locomotives are often diesel electric, so why are recreational boats like those on TF not? Uneconomic? Other reasons?
 
Wow!

Does that include new tanks and fuel for 5 years?? - Just wondering, and kidding... sort of!!

Okay, Soooo - Seeing as our 34' tri cabin Tollycraft performs just fine with twin 1977 255 hp carburetor gasoline engines:

I'd simply get the best new same size engines with maybe a little more hp designed in, such as cam, piston, head increased hp output.

I know that same 350 cid engines, in 2017, can turn out a bunch more hp. if desired. Instead of 255 hp. - 300 hp each would be a nice touch! :thumb:

Thanks Unc! :D
 
Wow!

Does that include new tanks and fuel for 5 years?? - Just wondering, and kidding... sort of!!

Okay, Soooo - Seeing as our 34' tri cabin Tollycraft performs just fine with twin 1977 255 hp carburetor gasoline engines:

I'd simply get the best new same size engines with maybe a little more hp designed in, such as cam, piston, head increased hp output.

I know that same 350 cid engines, in 2017, can turn out a bunch more hp. if desired. Instead of 255 hp. - 300 hp each would be a nice touch! :thumb:

Thanks Unc! :D

So, with unlimited money available your wouldn't go twin small diesel?
 
If we still had the Fu Hwa, I would remove the Perkins, convert to gasoline and hang a couple of small outboards on it.
 
Remove - Volvo Penta D4-260 & DPH-A drive.

Install - Volvo Penta D4-300, gear, and Arneson surface drive.

Jeff
 
Id have no hesitation re powering with a Hyundi Seasall

Extremely smooth and quite compared to my Cummins 315


If money was no problem I buy a Gardner and have a wooden boat built around it :smitten:
 
I'd have to take an holistic view of re-power to include transmission and props. Then it would be:
Remove JD 6068 twins 201HP each, Twin Disc 506 gears and 30 x 28 3 blade props.
Install JD 6068 twins 400 HP each, Twin Disc gear with sufficient rated capacity and 150 kW electric motor/generator on each shaft, and Hundestadt CPP 4 blade props.

I could happily run at up to 10 kn on one engine, but be using both props. Or I could run both engines and likely get to around 20kn. Occasionally.
 
The problem with Gardners is you HAVE to polish all that metal. No choice.
 
Money no object? Steam engines please!! (2) I would like the quiet and smoothness. Some kind of tidy burner system burning diesel.

Steve
 
I think a fresh pair of Cummins 6BTA 370 Diamond factory refurbs done the "Seaboard Way" would put a big smile on my face. 25+kts cruise and 30+kts on the pins, but smooth and quiet at lower speeds all day long when needed. I prefer the simplicity of mechanical diesels.

That's what my uncle told me he wanted me to do just before he passed . . . . really, he did. Besides, that way there will still be something left over for my brothers and sisters too.:socool:
 
How would I get the engine out would be a question I would need answered first.
 
How would I get the engine out would be a question I would need answered first.



EASY
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Exactly.
Easier and cheaper to rebuild in situ if the original motor was the right choice.
 
Its a toss-up between old school slow revving Gardner, and new school all electric system.
 
"Interesting thought. Ships and locomotives are often diesel electric, so why are recreational boats like those on TF not? Uneconomic? Other reasons?"

No reason to, no advantage a cruiser could use , vast expense and complication for only bragging rights , perhaps in Seattle , or San Fran.
 
While I didn't have the rich uncle to fund my project, I did pull out a low hours Cummins 6CTA 450 HP and swapped it for a John Deere 4045TFM75 135 HP. Very happy with the decision, but then I like to cruise at a gentleman's pace.

Ted
 
I would probably go with less hp than the Perkins 135. Maybe a Kabota 100 hp or so from Beta Marine . My rich uncle put one of those in his sailboat and loves It. He said the guys at Beta Marine set up him up pretty good to do the install himself .
Hey Menzies since I'm being conservative can I throw in a new gennie as well ?
 
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I would keep my turbo charged Mercedes. Quiet and easy to work on. I would however like a stern thruster. Since it is a single, I love my bow thruster but to have both would be fantastic. Um and stabilizers too please?
 
So, with unlimited money available your wouldn't go twin small diesel?

When you say small diesel... please define.

I don't mind cruising at just below hull speed, often doing so... but - I also really like cruising on plane at 17 knots with top end of 22+/- knots. I figure that by putting high tech 350 cid., 300 hp. gasoline engines in place of current 1977 350 cid., 255 hp. engines that our little Tollycraft would have a planing cruise at near 20 knots with WOT approaching 25 knots.

Also, please do understand... I've been around boats, trucks and cars for enough decades [i.e. six] to well understand the plusses and minuses and need for or no need of both diesel and gasoline power sources.

Couple items to mention regarding powering our 34', 21K lbs. loaded, self contained, comfortable, tri cabin Tollycraft that has a hard chine, minimal draft [34"], planing hull - In effect... a fairly fast and agile little boat:

1. There is little to no need for high torque diesels
2. Gasoline engines are several-x simpler to maintain, with less general/expensive item breakdowns and maintenance costs
3. Gasoline mechanics when needed are more plentiful and cost less per hour
4. Diesel fuel and diesel exhaust smells. Properly contained gasoline and its exhaust from well tuned engines is basically order less
5. Diesels are noisy - Gasoline engines purr in comparison
6. Diesels are heavy compared to gasoline engines - something our little 10.5 ton planing hull boat needs not regarding extra weight to carry around
7. Although diesel fuel turns out a smidge more BTU per gallon, it often costs more at the pump too. Additionally, although diesel power usually gets a bit more nmpg than gasoline engines - with today's technology that difference is getting less and less
8. Although all diesels are touted to have a magical capability to last untold numbers of thousands upon thousands of hours - that is true for some of the older NA, non turbo, HD monsters - but it sure is not true with some of the new models
9. Top of the line brand gasoline engines, when used correctly and thoughtfully, can last 4,000 ++ hours with rebuild or full-on new engine replacement cost a fraction of diesel cost
10. Although gasoline fumes are considerably more explosive than diesel and gasoline exhaust carbon monoxide can kill... modern diesel turbo and "run-away" diesel failures have their own sector of fire-creating failures. Also, diesel vapor sprayed on too hot a surface can ignite in a "blow up" manner... although not as severe an explosion property as gasoline. That said - diesel engines and gasoline engines as well as their fuel storage, its transmission and general use need to ne thoroughly respected and cared for appropriately.

Soooo... all n' all... For our little boat I chose gasoline engine - odor free, quiet operation, easy maintenance, nearly instant spare-part availability and mechanics' low costs over those of diesel engine. Anyway - I don't want to be frivolous with my dead unc's $$$$ - LOL

Oh yes, one more thing: If our little 34' 10.5 ton boat was some 45' + weighing 15 + tons - I'd have diesel engines... not gasoline!! :D
 
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So if you are told that a rich uncle had died and left you enough money to repower your boat with anything you wanted, single or twins, what would you repower with and why?

Would you upgrade your existing with new of the same, go with something else, totally redesign your ER structurally and change from one to two or vice versa.

What, and why?


I'd probably just change the current 6CTAs to more recent QSMs. Probably the easiest "upgrade" that could be made... if I'd be looking for something other than a pair of new or reman 6CTAs.

The hull, and overall layout, isn't particularly optimized to switch to pods, I think.

-Chris
 
All electric, with a megawatt LFP bank and a huge bespoke solar array that unfurls, shading the whole boat when charging, rolls up to nothing when under way. Genny as a rainy-day supplement only. . .
 
I would keep my turbo charged Mercedes. Quiet and easy to work on. I would however like a stern thruster. Since it is a single, I love my bow thruster but to have both would be fantastic. Um and stabilizers too please?
WOW! Your not asking for much, Donna! There must be something you left out! Cocktails, Panama hat, etc? :blush:
 
I'd go for something like this, but it would probably sink our boat :eek:

 
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