Don't fight the Power

Sep 22, 2018
1,869
Hunter 216 Kingston
If I were King..... It would be gen-set low in the boat. Say in a bilge type area. It would power all the electrics including electric drive.. Oh and diesel gen-set for sure.
Since your king and therefore have lots of $$€€££¥¥ you could replace the metal keel with a battery the same shape and size!! ;)
 
Apr 8, 2011
768
Hunter 40 Deale, MD
Here is a good video on jet drives and explains why they are not used on sailboats.
Interesting video - and it makes sense RE the speed range where a water jet is practical. I'll just say that the Assault Amphibian Vehicles the Marine Corps uses has a max speed of 7 knots in the water - and its not because the 28,000 pounds of water jet thrust aren't trying to make it go vaster. But efficiency isn't necessarily the name of the game in military applications, so it makes sense it might be an exception. Thanks for posting the video - I learned some things.
 
Apr 5, 2009
2,774
Catalina '88 C30 tr/bs Oak Harbor, WA
In the amphibian vihicles, they are after sallow draft and imunity from hitting the prop on an abstruction and getting damaged. Not usually a sailboat problem. if you hit the prop on the ground you are already missing a really important bit of kit. :yikes:
 
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Sep 22, 2018
1,869
Hunter 216 Kingston
Jet planes have a reverse. Some prop planes also have a reverse. As mentioned above, they use panels to redirect the thrust and the prop blades rotate.

Keel? Rudder? They are basically the same thing but one is smaller and turns while the other is fixed. Water flows around them the same way, forward or backwards.

I agree that the problem for in-the-water boats is marine growth. But I am sure that can be fixed by adding doors and then pumping in fresh water forcing out whatever is in the jets.

This can be done. I have faith.
We are in true thread hyjack mode here but....
What if the jet could also rotate to aid in close maneuvering like an Azipod(sp)??
 
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Oct 19, 2017
7,732
O'Day 19 Littleton, NH
Twin electric tunnel drive right through the twin keels. Reversible, reclaimable, and why not have a side thruster for walking sideways up to a seawall between boats?

-Will (Dragonfly)
 
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TomY

Alden Forum Moderator
Jun 22, 2004
2,758
Alden 38' Challenger yawl Rockport Harbor
If you could have any type of power in your boat, which would you choose? Which do you believe is the cheapest and easiest to maintain and live with?
I'd probably go for some sort of hybrid on my boat. If starting with a new design, I'd go EP for the way I sail. Old boats like mine aren't well suited for solar panels and general space for retro fitting mechanicals.

To the second part, I'm doing what most of us do with old boats: Maintaining the auxiliary power I have.

If you have a good reliable engine on your old boat, maintaining it is the cheapest and probably easiest way to go. Unlike cars, old boat engines, some from the 70's - even 60's, aren't that rare.

My entire 1961 sailboat is obsolete. Why change now? :)
 

TomY

Alden Forum Moderator
Jun 22, 2004
2,758
Alden 38' Challenger yawl Rockport Harbor
Interesting that a high proportion of respondents indicate an interest in electric!
I thought so too. It wasn't that long ago that E-cars were laughed at. :)

The E propulsion industry seems to have moved much faster. I'm surprised.
 
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Sep 22, 2018
1,869
Hunter 216 Kingston
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Oct 10, 2011
619
Tartan 34C Toms River, New Jersey
Can you give me a ballpark number for how much you spent rebuilding your A4?
In my case it was replacing the cam, valves, springs and carb. I had the pot (head) fly cut and checked for cracks. The lower unit was in decent shape, there was a small amount of rust on one of the cylinder walls so I checked with Ken at Moyer Marine and decided to clean with a 3M pad and leave it alone.
The carb was bought used from a fellow SBO member on used gear, which I rebuilt. I also replaced the exhaust pipe from the motor to the muffler.
All work I did myself other then the machine shop. Parts came to approx. $500. In my younger days I was a avid motor head so working on this flat head was easy.
Ken at Moyer is a great source for information and procedures. You can always message me if you have any questions.
 
Feb 14, 2014
7,400
Hunter 430 Waveland, MS
Geeeezz guys I am going to delete that comment.
Sorry it was a bit off topic, but thought provoking.
 
Sep 22, 2018
1,869
Hunter 216 Kingston
Geeeezz guys I am going to delete that comment.
Sorry it was a bit off topic, but thought provoking.
Well it was about propulsion so not too far off topic ;)

If you delete the comment future readers of the thread will really wonder how the discussion about ICE suddenly jumped to water jets ;)
 
Jun 14, 2010
2,081
Robertson & Caine 2017 Leopard 40 CT
My entire 1961 sailboat is obsolete. Why change now?
I'm obsolete, too. :thumbup: Change is interesting, though.
More thread drift: Read an inspiring news story today "62-year-old former Marine sets Guinness World Record by holding plank (position) for over 8 hours". Hey, I'm only five years older... maybe I should set a smaller goal and try for 8 minutes. :)
 
Sep 22, 2018
1,869
Hunter 216 Kingston
I'm obsolete, too. :thumbup: Change is interesting, though.
More thread drift: Read an inspiring news story today "62-year-old former Marine sets Guinness World Record by holding plank (position) for over 8 hours". Hey, I'm only five years older... maybe I should set a smaller goal and try for 8 minutes. :)
Pretty amazing guy. This is his quote after he finished. Oh yeh he did 75 push-ups
AFTER he finished!

If there's a lesson to be learned from this, Hood said it's this: "Anybody can do what I do."

Words to live by! :)
 
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Apr 5, 2009
2,774
Catalina '88 C30 tr/bs Oak Harbor, WA
Wow I thought the pool was going to explode!!

You would think they would have come up with a little better mount than a ratchet strap!!! :)
This has the same problem for slow sailboats as all other jet drives. They get their efficiency from fast moving water entering the jet.
 
Jan 19, 2010
1,169
Catalina 34 Casco Bay
Since your king and therefore have lots of $$€€££¥¥ you could replace the metal keel with a battery the same shape and size!! ;)
Doubtful....While it would be nice to keep the weight low in the boat, Murphy's law states that heavy batteries that replace keels will regularly fail and require replacement on an all too often schedule..