CS 25 inboard diesel engine?

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Stian

CS 25 inboard diesel engine?

Post by Stian » Thu Jun 28, 2018 7:18 am

Hello everyone.

I've been thinking for a while about building my own boat, looked at man different ideas and possibilities and have comed to the conclusion that I really like this design.

But my thought is, because gasoline is quite expensive here in Norway, has anyone thought about building this boat with an inboard diesel and a stern drive? Thinking about 200-250 hp Volvo Penta or something similar.

I know about outboard diesels, but these engines cost to much.

What type of reinforcements must be made to the boat?

Regards

Stian from western Norway



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Evan_Gatehouse
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Re: CS 25 inboard diesel engine?

Post by Evan_Gatehouse » Fri Jun 29, 2018 10:50 pm

Hello Stian,

I know gasoline is costly - but most pleasure boat owners only use their boat 100-200 hours a year. So....

say 10 years of owning boat x cost of gasoline x 200 hrs + cost of gasoline outboard (maybe 50 L/hr??) and compare to

10 years of diesel @ 200 hrs + cost of diesel stern drive and see if it really makes economic sense. D3-170 = 20 L/hr @ 3250 RPM / 160 HP

If it does, I think it might be possible. A smaller D3-170 (170 HP) model might make more sense if you can live with a bit less speed. Only about 100 kg more than a 250 HP 4 stroke gasoline outboard.
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Re: CS 25 inboard diesel engine?

Post by fallguy1000 » Sat Jun 30, 2018 9:10 am

Don't forget the loss of cockpit.

If you are willing to sacrifice top end speed and cockpit loss; it seems possible on the economics, but the weight of the inboard is also a factor. When I researched using diesel; the comparable diesel inboards to a 270# Yamaha F70 were about 450# and those were all tiny; too tiny for a planing hull like the CS25. That means a 200 hp engine is most certainly heavier than 200 ob.

So check into that. You might need to build in foam even to offset the weight; not sure.
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Re: CS 25 inboard diesel engine?

Post by jacquesmm » Sat Jun 30, 2018 10:08 am

It has been done: Cummins with stern drive.
It was a CX25 (the one with cabin) and for a while, we had pictures at the web site but he made some ugly modifications to the cabin and I removed the pics.
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Re: CS 25 inboard diesel engine?

Post by Spokaloo » Mon Jul 09, 2018 12:37 am

Stian, the LB26 would be the right hull for your engine, and would be a lovely hull for your waters as well.

E

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