Miles per Gallon

[Jason]

Have you guys ever tried figuring out your miles per gallon on yor boats? It obviously is going to vary how you run the boat and how much weight you are pushing.

My V172 averaged about 2.5mpg on Monday. Pretty much running WOT the whole time.

[Hyperacme]

I wanted to do mine ... but keep forgeting to reset GPS ...

[Green with Envy]

Previous boat was an open-bow crestliner, 17ft.  30 gal tank, 90 nautical miles per tank. So, about 3 miles per gallon.  Had an OMC 4.3 V6.

Havent checked Green yet.  Maybe this year.

I would have thought outboards have a different mpg usage.  Yours looks right in line.

Allan

[David CVX-16]

2.5 MPG seems low.  I used to calculcate roughly the miles driven on a long river trip and divide by the gallons used, and thought I got about 4 MPG on the 115 HP in-line 6 cylinder Merc. Now that I have the GPS that calculates the trip distance, I can divide the GPS trip distance by a full tank used, 5.75 gals (amount I put in a tank). In any case, the old Merc's are gas hogs compared to the new 4-stoke engines.

Currently on Craigslist for sale is an Eliminator with a 8 carb 275 V-8 Johnson outboard. His carb tuning was $1,000 last fall and I bet his MPG is really low at top speed.

Surprisingly, an Allison performance hull with a 225 HP Mercury Promax gets 4 MPG doing 90+ MPH and with a 90 HP Honda 4-stroke Honda got 12.8 MPH at the best speed and 8 MPG at 60 MPH. But the initial cost is about $50,000 for boat and motor. "The SS 2000 SuperSport, four years in the making, is designed to be the most efficient high performance boat in the world. Independent tests reveal ?an unheard-of fuel mileage of 12.8 mpg, and over 10 mpg at 60 mph.?

   

[Jason]

I am not sure what my CV16SS is but I know it is A LOT better than the V172. Seems like I can run around all day on a 1/2 tank (8 gallons) of gas.

[David CVX-16]

Your low MPG may stem from some engine tuning problem yet to be addressed that will increase your MPG.

[MarkS]

If I stay at or under 3600 RPM (26 MPH) I can run about 3 hrs on 12 gal = 4 GPH or 6.5 MPG approx..
Hammer it to WOT (5200 RPM 42 MPH or close to it) and you can cut that in HALF pretty much.

Keep in mind I go by myself most of the time, not much gear in the boat.  If you added people/weight, I'm sure it would make a big difference.

[84carlson]

A full day at the lake $60 in gas, an evening at the lake $25....another $30 for the tow vehicle...priceless....

[Eric_Michael]

Uhhh...yeah.  Miles per gallon.  Not something I want to think about.  When I went out testing after the fuel pump & sensor repair, I ran ~20 miles.  It took ~10 gallons to fill up.

Like I said, "testing".  5k RPM all the way, and what a ride!   

-Eric

[Jason]

It is sad to think about haw crappy the milage is on these old boats but then you think about how often you actually go out and most hobbies are not free so it's not all that bad.
I more wanted to figure out how many miles I can go on a tank of fuel so when I am out in Voyageurs I can figure out if I'll make it to the next petrol station or not! It just got me thinking about what "average" might be.

[OleRed]

I have been meaning to reply to this thread, but have not taken the time.
Last year, running the 650 cfm carb, jetted for performance, showing off and giving rides at the lake by my house, I have burned up as much as 13 gallons of gas in 50 minutes, wot most the time of course,  after some de-tuning, changing to the 600 cfm carb, before we came to Red Wing, I got just about the same performance, and a Lot less gas consumption.
on a 140 mile Arkansas river trip from webers falls, Ok to Van Buren, Ark. and back the same day, going down stream 10 / 11 mph, about 1800 rpm, took about 5 1/2 hours and used 16 gallons of gas ...  4.3 mpg
return trip, 2800 rpm @ 32 / 34 mph using 12.5 gallons of gas ... 5.6 mpg and was back on the trailer in  2 1/2 hours.
on our fall folage tour up the Arkansas, me and the Fox, a pic nic lunch and a relatively cool day, from Webbers Falls, Ok. north to the Grand River, up it a ways for lunch, back to the Arkansas, then we went on north of Muskogee, Ok. about 5 miles, back to Webers Falls, topped off at 13 gallons ... 5.7 mpg.

http://www.youtube.com/watch?v=t57meFR7Pfs&feature=related

http://www.youtube.com/watch?v=VPRbpawcTH8&feature=related

[Hyperacme]

Red ...
That's called ... Haveing your cake ... and eating it too !

[V153]

I shudder to think what my mpg is. I can tell you that running the Lightspeed my boat would cruise a lil under 30mph @ a lil over 3000rpms. A magic # so I'm told. Reasonably economical at that setting. However running the SRX chopper is a completely different story. Doesn't want to stay hooked up @ those kind of cruising speeds.

Fuel economy is a major advantage the IO guys have over the older 2 strokes. These things guzzle gas like no tomorrow. I once burned up 15gal in an afternoon!?   

[Jerry]

Glad i got a 35 gallon tank.