Fuel consumption per hour

T

turnrloose

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What would the fuel consumption be at cruise speed of approximately 20-mph with a 350 inboard on a 27' sportfishing boat?
 
No where near enough information provided to give a reasonable answer.
 
+1

However, if you could tell us what the airspeed velocity of an unladen swallow is, someone may be able to come up with an answer.

Seriously. It ain't gonna happen. A 27 footer with a 350 is not going to achieve a 20 mph cruise with a single 350 inboard. It may see 20 mph as top end in a slack tide or following sea.
 
"What would the fuel consumption be at cruise speed of approximately 20-mph with a 350 inboard on a 27' sportfishing boat?" -- turnrloose

Don't know. My boat was a 27fter w/ twin 150 optimax outboards, but definitely not a SF. Cruise speed was 30kts, fuel rate at cruise was 13.5 g/hr. At 20 kts the boat would have been in the "no-go" zone, that is, "on the hump" and climbing uphill, the worst possible of all speeds and definitely not "cruise".
 
Assuming Gas.
Ballpark without knowing boat, weight, props, conditions, top end, engine make, etc.
I am gonna guess somewhere between 10 and 20 GPH.
 
I was just curious whether I would be better off paying more money to get a boat with a diesel engine or less initial cost for one with a gas engine. The boat I'm interested in has an empty weight of 5500 lbs. and I was looking to use it for offshore fishing. It's a Luhrs 27 ft.
 
My next door neighbor has a Luhrs 27' with a 265hp Chevy inboard, direct drive. At 20 mph he's burning about 22-24 gph depending on water conditions. (Just called and asked him)

Bob
 
Unless that boat has a fairly flat bottom, it really needs a big block (454)to push it around.
Gas vs diesel....You'd have to put many, many hundreds of hours to recoup the difference in extra cost of a diesel powered boat vs the extra gas you would be using. The many thousands you will spend to get a diesel will buy a whole lot of gas.
 
^not doubting your neighbor, but that seems like a lot. I have a 45 foot, twin diesel, 32,000 lb
At 20 Kts, I'm doing about 32gph. I know its not a great comparison, but a boat that size should do a lot better.
 
The 38 and 39 foot Bayliners at 20-22,000 pounds get one statute mile per gallon. For a boat 50% heavier to get the same sort of mileage is astounding. My Meridian 40 footer doesn't. Not by a long shot.

I have a 26 foot Bayliner with a single 5L fuel injected engine and Bravo III that gets 2.0 mpg. That is, it shows 12 gph on the meter at 25 mph.
 
quote:
Originally posted by getakey

^not doubting your neighbor, but that seems like a lot. I have a 45 foot, twin diesel, 32,000 lb
At 20 Kts, I'm doing about 22gph. I know its not a great comparison, but a boat that size should do a lot better.

Click to expand...


Math or fuel flow monitor at that speed and RPM?
 
I had a newer Rinker, 28 loa, 6800 lbs, with a 350 mag and merc b3 outdrive and it got 2.0 mpg and burned 13gph at 3400 rpm cruise. I had smartcraft so those number are accurate.

Good luck
Niles
 
quote:
Originally posted by getakey

^not doubting your neighbor, but that seems like a lot. I have a 45 foot, twin diesel, 32,000 lb
At 20 Kts, I'm doing about 22gph. I know its not a great comparison, but a boat that size should do a lot better.

Click to expand...


All I know is what the man told me.

Bob
 
quote:
Originally posted by KiDa

+1

However, if you could tell us what the airspeed velocity of an unladen swallow is, someone may be able to come up with an answer.

Click to expand...


It depends on whether you are talking about an African or European.
 
quote:
Originally posted by rbmitchell

The 38 and 39 foot Bayliners at 20-22,000 pounds get one statute mile per gallon. For a boat 50% heavier to get the same sort of mileage is astounding. My Meridian 40 footer doesn't. Not by a long shot.

I have a 26 foot Bayliner with a single 5L fuel injected engine and Bravo III that gets 2.0 mpg. That is, it shows 12 gph on the meter at 25 mph.

Click to expand...


sorry, I see that I had a typo. I meant 32gph, but my main point was that the 26 fter should get way better and your experience with your bayliner is exactly what I would expect
 
can the moderator edit my earlier post to correct to 32gph?
 
quote:
Originally posted by getakey

can the moderator edit my earlier post to correct to 32gph?

Click to expand...


Go back to your original post and just above it you will see a page with a pencil over it. Click on that page and do your own edit.
 
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