Determining Fuel Usage

kbangma

We're bringing a 40 ft Express cruiser home from NJ to Newport.  Has anyone done this trip and how can we determine fuel usage per hour at cruise speed of 20 knots?

LaRea

Congratulations!  Welcome to the forum!

What's the propulsion package?  If she has gas 496 with Bravo 3 outdrives, you can expect around 0.75 mpg at 30 mph, assuming good weather and decent bottom paint.  You can probably slow down to 23 mph (20 kts) if you want, but you'll burn a lot more fuel.  The boat's much happier at 27-30.  

With v-drives, 23 mph might be right, but it won't get 0.75 mpg.  

Willhound

More like a third of that. 151 miles ÷ .75 mpg = 201 gallons. 

Handymans342

What motors?

kbangma

496 Mags

Glassguy54

Where in NJ, and to Newport RI? Is that around 400 miles by sea? So maybe around 600 gallons of fuel?

Glassguy54

I just looked at a distances between US ports chart (https://nauticalcharts.noaa.gov/publications/docs/distances.pdf) and from Port Newark NJ to Newport RI, they are indicating more like 151 miles.

Handymans342

600 gallons to go 151 miles? OMG is that right?

Handymans342

201 times 4 is OMG

Dream_Inn

Well, I'll say for 150 miles, plan on using somewhere between 200 - 240 gallons of fuel.  I've done a 160 mile trip to VA beach for 4-5 years in a row and I burned anywhere from 210-250 gallons, depending on conditions.  You should be able to make it on one tank, but if conditions are rough I'd keep an eye on fuel level just in case. 

@LaRea is very close to the burn level of .7 - .75mpg.  Sorry @alswagg , but 0.9 is only pristine days going with tide.  (I've seen 1mpg for brief periods)

What year is your new 400? We love our 400!  This will be our 7th summer with it!  You'll find that 30-32mph is the perfect cruise speed.  Welcome to the forum!

Handymans342

@Dream_Inn So if I burned 120 gallons to Key West at 33 MPH thats pretty good hey?

Handymans342

A clean bottom paint slows a boat down??

Dream_Inn

Alswagg said:

I just remember doing the fuel consumption test. Now, don’t overload the boat and have a clean gel coat bottom   Bottom paint will slow it down and burn much more fuel.  Sleek, clean, and sexy 

Yes, mine is bottom painted, but not overloaded.  But, I do ride often with another boat that is the same, but no bottom paint, except it has B3 drives and he burns very close to the same as me, maybe just a tad better.  Although I do seem to burn a little better (more around .08mpg) with the new HM props now.

Handymans342 said:

@Dream_Inn So if I burned 120 gallons to Key West at 33 MPH thats pretty good hey?

Doesn't sound too bad.  What was the distance?

Handymans342

Dream_Inn said:

Alswagg said:

I just remember doing the fuel consumption test. Now, don’t overload the boat and have a clean gel coat bottom   Bottom paint will slow it down and burn much more fuel.  Sleek, clean, and sexy 

Yes, mine is bottom painted, but not overloaded.  But, I do ride often with another boat that is the same, but no bottom paint, except it has B3 drives and he burns very close to the same as me, maybe just a tad better.  Although I do seem to burn a little better (more around .08mpg) with the new HM props now.

Handymans342 said:

@Dream_Inn So if I burned 120 gallons to Key West at 33 MPH thats pretty good hey?

Doesn't sound too bad.  What was the distance?

180 miles

Dream_Inn

Alswagg said:

Yes. Bottom paint causes so much drag.  Some are better than others.  Best is to keep the bottom pristine gel coat   Either on a lift or trailer.  Do not let any growth of algae start    

I do keep her on a lift, so she stays clean.  Boat was already bottom painted when I bought it, so I thought it'd be best to maintain the bottom paint.  Some people in my marina just let it all wear off, but that can't be very good for resell.  I would think the next owner would have to clean it all off, put new barrier coat and then paint if they were leaving in water again.

Black_Diamond

A lift is just not always doable. At least by me. Plus the lift cost, hauling in/out every season adds to the cost. Then no a/c when lifted either. I switched to VC-17 two years ago for bottom paint. Stuff sailboaters use, esp racers. 

Handymans342

Black_Diamond said:

A lift is just not always doable. At least by me. Plus the lift cost, hauling in/out every season adds to the cost. Then no a/c when lifted either. I switched to VC-17 two years ago for bottom paint. Stuff sailboaters use, esp racers. 

You dont need AC in Michigan!!

zaverin1

I know my 120 gallon tanks will give me about 110-120 miles from full
to e.
i Cruise at 24-25mph

zaverin1

That’s 3200-3400 rpm

Stodge

zaverin1 said:

I know my 120 gallon tanks will give me about 110-120 miles from full
to e.
i Cruise at 24-25mph

I used to get around 1.4MPG in my 280.  I get between 1 and 1.1 in the 342.

Dude_Himself

My 280EC with the 496 MAG will routinely get 1.7 MPG without trimming. With the VesselView I can get 1.9 MPG trimmed. It'll do about the same at 900 RPM.

Handymans342

900 RPM? That's idle Speed

Black_Diamond

@Handymans342:  was 95+ over memorial day weekend. Yes to the A/C! lol

Handymans342

Black_Diamond said:

@Handymans342:  was 95+ over memorial day weekend. Yes to the A/C! lol

Thats hotter than here!!