Just installed Garmin GFS10 Fuel Sensors, What is your economy?f

Wildboating

So I just installed a new Garmin 740xs and GFS 10 fuel sensors in our 342 for a trip to the islands.  I found that at my wot 3800-4000 rpm's I was getting .08mpg and burning  approximately 30gal per hour at 27-30mph depending oh wind and waves.    Does anyone else have fuel sensors on board, if so what are you seeing?

Dream_Inn

well, if you are getting 0.8, at 30mph you'd be around 38 gal per hour.  Ask me how I know?  well, that is my best burn rate on a the very best calm day.  I'm usually 0.7 mpg at ~32mph...burning 43-45 gph.

MarkB

How did you come up with 0.8 mpg? 30 mph / 30 gph = 1 mpg.

Wildboating

MarkB said:

How did you come up with 0.8 mpg? 30 mph / 30 gph = 1 mpg.

I get that the numbers do not line up, the reason I asked what others are getting is because these seem inaccurate to me.  I just installed the equipment and did a 120+ mile trip, this is the info the equipment provided me.  I will have more info once i compare the calculated fuel burn to how many gallons it requires to fill the boat back up.  

Lifes Good

340 and 320 at 3800 rpm regardless of 5.0 or 5.7 will get 1 mpg.  Done!

sdjavalina

we have a 330 fiesta vee and 5.7 mercs EFI. what kind of fuel consumption will we get..? at say 2500rpm and 18mph

jme097

How are you staying on plane at 18 mph at 2500 RPM? Definitely not on plane at that low of RPM

Handymans342

Depending on load its not good anyway, say 1.2 to 1.8 MPG.

SeaHare

310 w/ 5.7 carbs = 1.25-1.40 mpg @ 30 mph

Stodge

I have seen as high as 1.2MPG in good conditions.  It's closer to or a hair below 1MPG when it gets choppy.  I've gotten 28.8MPH burning 24.2GPH turning 3600RPM

frodo13056

On my  2008 320 (5.0 Merc's 260 HP with B3 drives), my absolute best MPG is 1.20 at 31.3 MPH burning 26 GPH and about 4200 RPM.
My best top end is 37.1 MPH burning 36 GPH and 1.03 MPG running about 4700 - 4800 RPM.

MarkB

Single 350 MAG on a 260 EC I get 15 gph at 30 mph. So 2 MPG.  I'm loving that!

Michael T

MPG depend on drjve/trim settings, load, temperature,  humidity, height above sea level and water and wind conditions -  so my MPG vary across the boating season from about . 9 to 1.5 MPG.

Mike_G

 MarkB said:

Single 350 MAG on a 260 EC I get 15 gph at 30 mph. So 2 MPG.  I'm loving that!

WOOT WOOT!!!  I'm just a tad better than that (less weight?).  With gas being hopefully under $2.00/gal this year, boating is gonna feel "free" compared to years past.     -=Mike G.

Michael T

A lot of gas is going great to get burned -  "just because. This summer I'll go Sea Ray hunting.  Open Season LOL! 

SeaHare

PFFT!! I see most marinas being $1+ more than street gas this year... watch....

Handymans342

Can't wait to test mine now that the throttle cables have been properly replaced and adjusted ###!!!!!!

sdjavalina

@jme097 I was guessing at mph, this is a new boat to me my 27 ftr did a good cruise at 1850 to 2200 rpm. not on plane...! we do a lot of slow cruise in. No our rinker rolls up on plane and goes about 41 mph Im guessin she would burn, 2,5 gpm also at that rate if not more with twin 5.7 mercs.

Dream_Inn

@handymans342 I see diesel around here about 50 cents a gallon more.   You might be spending more than me!!  LOL

Handymans342

No way. Diesel was always cheaper than gas at the dock. You must be looking at land prices

Dream_Inn

You haven't looked lately??

[Deleted User]

FV250 single 5.0L, smooth conditions, no current. 4K rpm, 25 mph, 12 gph, about 2mpg. Add some wind, chop and swell and an opposing current and 16 - 20 gph is more like it. It's a rare day on the Pacific you get smooth water, but it's sure fun while it lasts.
Andy

Handymans342

Cheaper here in FL. What is it at Spring Cove Dream?

Dream_Inn

Handy, locally near my marina I can get both right now near $2/gal.

Handymans342

Well that's more like it

Dream_Inn

Yep, if they stay that way all summer, I'll be going a few hours every weekend this summer!

Handymans342

Down here diesel is cheaper at the dock but its 30 cents more at the pump. Go figure 

Michael T

They're intimidated by your diesel posse Steve. :-)