Fuel Consumption Question Merc 60HP 4 Stroke

[oldtortuga]

Hi all,
I know this question might go the way of "how long is a piece of string" but,,
under ideal circumstances wind, temp, current etc. running at about 1/2 to 3/4 WOT pushing a 1800 pound 28 foot pontoon boat with 4 people on board and the trim set just right.....
how many miles per gallon should I expect to get on my 2005 Merc 60 HP 4 Stroke EFI motor. I took the boat out Sunday under the conditions I just mentioned and got about 4 MPG as near as near as I can figure.
Does this sound reasonable to the group ??

 

[Silvertip]

Re: Fuel Consumption Question Merc 60HP 4 Stroke

Reasonable but rather meaningless since you don't have an odometer unless you have a gps unit. Fuel flow is best determined in gallons per hour and your 60 HP at wide open throttle will burn 6 gallons per hour. At half to 2/3 throttle it will be somewhere in the 3 - 4 gallons per hour range. Now the interesting part is that you can run wide open and consume the same amount of fuel (or very nearly so) as if you ran at 1/2 or 2/3 throttle. Why??? Because you have to run longer to get where you are going at lesser throttle settings.

 

[oldtortuga]

Re: Fuel Consumption Question Merc 60HP 4 Stroke

Thanks for the quick feedback.
I am confused though (not an abnormal state for me, smile,,,).
Best as I can recall we ran 1 hour 45 minutes and covered a good 16 miles (based on known mile markers in the river) (8 with the current and 8 against the current) . We started off with 2 topped off 6 gallon tanks. After we returned I refilled the used tank with a five gallon can and had about a 1/2 gallon of fuel left in the refill can.
Does this make sense ??
I know its no big deal but I would like to be able to predict approximate fuel requirements for some fall river trips.
The wife and I don't run WOT, we sip coffee and run 1/2 maybe 2/3 throttle at most. My 20 plus year old pontoon misbehaves if I push her too hard (course. so does the missus)

 

[rickdb1boat]

Re: Fuel Consumption Question Merc 60HP 4 Stroke

I think you've answered your own question. You used 4 1/2 gallons to go 16 miles or about 3.5 MPG...