Can a boat carry to much fuel cruising?

[irwinsailor]

I have a extra tank that I tgought I would use for water but having a watermaker I was told that I should use the tank for fuel. I now have tankage for 238 gallons the unused tank is about 200 gallons. My usage is 2 gallons per hour. We one day hope to cruise the Caribean.

[Hampus]

If the watermaker breaks down, you'll be glad to have the extra water How much do you plan on motoring? Just estimating your cruisingspeed at 7 knots based on the size of your boat, I'd say your range is around 800 nm by engine? Isn't that enough?

[irwinsailor]

We carry about 300 gallons of water.

[Weyalan]

I think that yes, you can have too much fuel. Diesel does degrade over time, so you don't necessarily want diesel sitting in your tanks for too long. Also, extra fuel is extra weight and extra weight reduces performance / increases fuel consumption. So yes, you can carry too much fuel. Of course you don't actually have to have fuel in all your tanks, and if you leave the tank empty, and just fill it for your trans-oceanic passages, you get the best of both worlds...

[Hud3]

Gunner,

As Weyalan says, it's nice to have "extra" fuel when making an offshore passage, just in case the winds don't cooperate, but once in the Caribbean, too much fuel on board can be a liability, as it just provides a place for those evil diesel "bugs" that clog your filters to grow.

I have a single 85 gallon tank on my boat, and that's been more than enough. Diesel is fairly easy to get on a reasonable number of the islands, and you can stock up before moving on to the areas where it may be harder to find.

[keneatingsalmon]

Diesel weighs less than water if you are figuring for boat performance. So, if the water tank was always going to be full of water vs. always full of diesel. The diesel is better for less additional weight.

Ken

[Stillraining]

Go with water and shower away till your hearts content...well almost anyway....Thats what my crew would say anyway.

I say fill it full of Rum...

Shoot you could burn it for fuel in a pinch ..or bath with it...

[orion1]

We only have one fuel tank, an it is small, 24 gal. so we carry 4 cans for longer trips. Wish we had more permanant tankage but the cans work out well, and the fuel is fresh. We try to keep them below deck, well secured.

I have been trying to determine the typical consumption of a yanmar 3gm30 running at 2700 as opposed to full open at 3200. We make 6 knots at that rpm.

[David M]

Originally Posted by keneatingsalmon

Diesel weighs less than water if you are figuring for boat performance. So, if the water tank was always going to be full of water vs. always full of diesel. The diesel is better for less additional weight.

Ken

Diesel weighs 7.3 pounds per gallon and water 8.3 pounds per gallon which is a 12% difference

[Hud3]

Originally Posted by orion1

...I have been trying to determine the typical consumption of a yanmar 3gm30 running at 2700 as opposed to full open at 3200. We make 6 knots at that rpm.

There's a thread on that topic at http://www.cruisersforum.com/forums/...m30-12272.html

[orion1]

Thank you Hud.

You want to carry over 400 GALLONS of diesel???? Why on earth did you buy a SAILBOAT?

Seriously, if you feel you really are going to need motor that much, I worry that you are way too tied to a schedule. "We have to motor, we need to get to Island X by Tomorrow!" The problem with that attitude is that schedules kill sailors when they ignore weather windows. If you really need a boat with a 1000+ mile motoring range, you might be a lot more comfortable on a trawler.

[Ex-Calif]

I vote for Rum or Gin... Essentials, dontcha know?

Actually, tough call but I'd put on water. It's a sailboat after all...

[Talbot]

Without details on how many crew onboard, it is hard to figure a useage rate of water. Personally I would never put diesel on a water tank, there is far too much risk of getting cross connecting wrong and contaminating the other water tanks, and you will never really get the taste of diesel out without hurculean effort. If short crew and operating around the islands so you dont need the extra water, then leave it empty and enjoy the better performance. Yes I know that your boat is big, but that would still add a significant amount of weight, and even such a large boat would have a performance penalty.

[porttack]

If you keep that puppy sealed tight, you'll have 26.7 cu. ft. of flotation in your bilge; your boat will never sink. On the other hand, think what you could do with 26.7 cu. ft. of low storage space.