Flow Meters

[Freeebird]

5 GPH is roughly $13 an hour these days so if you even save just that then 350/400 hours will make the $5000 costs.

Seriously?

Everything you said above that pretty much voids this comment. Not just trying to argue, but the reality is, especially with a motor yacht, you run either hull speed (or maybe a little less), or you put it up on plane. Running in between where you know would burn more fuel won't happen unless sea conditions dictate you do so. Even then, it will take TONS of total running hours to make up the $5,000 you spent.

Funny, I used to think that buying Flowscans and rigging them on a portable setup, like the magazine, boat test folks do, could present a good business opportunity. You could spend a few hours setting it up, making a number of runs throughout the RPM range, and recording the results. You could pin down the sweet spot for both displacement and planing speeds, and make yourself a few bucks while saving the owner thousands.

Seems to me a cheaper alternative would be just to plumb in gauges that would show GPH usage. I can do a lot of math for the difference in savings, and seeing a big increase for no particular reason would let you know you have a problem.

[Westfield 11]

Isn’t the fuel flow data already in the computer of the new electronic engines? I thought all you needed to do in that case was to get the numbers up on a display. Fo instance, the display on my tender shows gph and mpg for the f.i. Yamaha.

[Freeebird]

Isn’t the fuel flow data already in the computer of the new electronic engines? I thought all you needed to do in that case was to get the numbers up on a display. Fo instance, the display on my tender shows gph and mpg for the f.i. Yamaha.

How dare you even mention computers and electronic engines on this forum!

Seriously, I did a quick Google search to find some fuel burn numbers for the 8V92TA and came up with references to this and other forums. There have to be some numbers from Detroit out there somewhere. Find that, and it's a matter of doing simple math and making a few runs.

It's pretty much a given that planing speed on this boat in question is going to be 1,900-2,100 RPM. Find the GPH number from Detroit, watch your GPS, and do the math to find your optimal spot. Do that while playing with the tabs and watching your GPS to find your sweet spot for them too. Anything you can do to pick up speed at the same RPM will increase your MPG's. I do this with I/O's and outboards to find the sweet spot where trim angles are concerned. Run it up to the RPM you want, then play with the trim until you get your best speed.

[racclarkson@gmail.com]

How much fuel would you have to save over the fill/run/measure/repeat method to break even with that $5K investment to let a computer do it for you?

My Hatt came with one Flo Scan on the port motor. It does help even at hull speed getting the absolute max knots before plowing. Also very useful determining best high cruise RPM v knots v trim v burn. My math is simpler than Freebird’s. I just multiply X 2. I’m just a simple man; sometimes I need a pencil and paper.

[Freeebird]

My Hatt came with one Flo Scan on the port motor. It does help even at hull speed getting the absolute max knots before plowing. Also very useful determining best high cruise RPM v knots v trim v burn. My math is simpler than Freebird’s. I just multiply X 2. I’m just a simple man; sometimes I need a pencil and paper.

Well there you go! Just spend $2,500 on one Flowscan and multiply x 2... and be a simple, kind of man (Skynyrd).

Maybe it's time for me to post this for the 237th time to let you see how relatively small these variations are. Yes, these are 71's, and the 92's will burn more fuel, but the percentages will still be the same. Look at page 5.

https://www.hatterasowners.com/Brochures/53ED/53EDA-0083.htm

[Pascal]

Yes seriously. . There are many people that do not know how badly fuel flow goes up as you reach hull speed. I ve seen so many boats running at a knot or so above hull speed pushing a huge wake the owner oblivious to the waste of fuel. Easy to waste as much as 5 GPH

Even water depth will affect your NMPG. Depending on LWL you may loose a knot or more at hull speed in water below 10/12 feet. On plane you may actullay go a little faster. So many factors

[Pascal]

Isn’t the fuel flow data already in the computer of the new electronic engines? I thought all you needed to do in that case was to get the numbers up on a display. Fo instance, the display on my tender shows gph and mpg for the f.i. Yamaha.

Yes electronic engines have flow meters and totalizers. I keep a fuel log day by day using the totalizer and estimating genset use. A simple spreadsheet on my phone with formulas already set to calculate fuel used, fuel remaining, NMPG etc. very useful. I just pumped 1100 gallons and my numbers where within 3% which was likely generator burn

[Westfield 11]

How much was the fuel with tax?

[Westfield 11]

Sorry, I just saw your post on the oil thread.

[Freeebird]

Yes seriously. . There are many people that do not know how badly fuel flow goes up as you reach hull speed.

Yes, but we're talking about Sadey who knows these things... along with most who are members of this forum.

Does your 53 have Flowscans from its DD days?

Had you not repowered, would you spend $5K of YOUR dollars to install them?

I think that's the primary issue here. My answer for my part is obviously, no, but to each their own. I don't think I'll ever reach the point where I won't find a better way to spend $5K on a boat.