Fuel consuption?

rickryder

Commander
Joined
Jun 24, 2010
Messages
2,722
I am looking for your input on how much fuel your older outboard consumes and any tips on improving the mpg..

I have a 76 577HG and only get about 2 mpg when running on plane at WOT....seems a bit low any thoughts??
 

roscoe

Supreme Mariner
Joined
Oct 30, 2002
Messages
21,750
Re: Fuel consuption?

I am looking for your input on how much fuel your older outboard consumes and any tips on improving the mpg..

I have a 76 577HG and only get about 2 mpg when running on plane at WOT....seems a bit low any thoughts??

Would that be 557HG ? 55 hp?

We usually measure fuel consumption in gallons per hour.

Most 2 strokes use approximately 10% of the rated hp, at wot (wide open throttle).

So your motor could use 5 gallons per hour at wot.

Back the rpm's off about 10%, and you will save fuel, and only lose marginal speed.

Dropping the rpm to approximately 75% of max will usually get you the best "mileage."

This applies to motor/boat combinations that are adequately powered.

A 55 hp on a 2200# boat is under powered, will not get on plane, and will just suck up all the gas on the planet.
 

rickryder

Commander
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Jun 24, 2010
Messages
2,722
Re: Fuel consuption?

That would be the motor 55 HP. I will try backing off the throttle a bit and see how she does... It's only a 14' trihull but I don't know the weight... If it goes by gallons per hour I ran the boat 12 miles @ 25 mph and used 5 1/2 gallons. I think I need to get some weight out of the boat:eek:Thanks for your input Roscoe
 

Unforcefull Force

Petty Officer 2nd Class
Joined
Jul 9, 2010
Messages
128
Re: Fuel consuption?

@ WOT for most of a full tank, I normally get 2.5 to 3.0 MPG.

1989 Force 125

-Mark
 

BuzzStPoint

Lieutenant Junior Grade
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May 27, 2009
Messages
1,003
Re: Fuel consuption?

Seems about right..

I have 1970 55hp. 6 gallon tank.

After about 1-2 hours of cruising around the river the tank will be close to empty.
 

SweeperForce

Chief Petty Officer
Joined
Feb 7, 2010
Messages
487
Re: Fuel consuption?

That does sound low. I got a 150 hp and I burn about 5 gal on a 2 hour trip down the river a few times.
 

Unforcefull Force

Petty Officer 2nd Class
Joined
Jul 9, 2010
Messages
128
Re: Fuel consuption?

It all depends on how you are with your throttle. I can putt around on the river for a few whole days without getting gas. People have to remember to include the " X " factors when stating how much fuel they are consuming.

A: ) RPM operating range / throttle position (1/4, 1/2, 3/4, WOT)

B: ) Distance traveled.



If you are not hammering down on the throttle all of the time, even if you back off 1/4, you can increase 2-4 MPG

If I take it easy, then I can more than double my MPG. WOT though, the average is usually 2.5 to 3.0 MPG, which is what I get and most of the folks get where I dock.

Some motors suck more gas than others as well. Boating isn't a cheap hobby! Always plan to use alot of gas so you are never disapointed!

-Mark
 

roscoe

Supreme Mariner
Joined
Oct 30, 2002
Messages
21,750
Re: Fuel consuption?

That would be the motor 55 HP. I will try backing off the throttle a bit and see how she does... It's only a 14' trihull but I don't know the weight... If it goes by gallons per hour I ran the boat 12 miles @ 25 mph and used 5 1/2 gallons. I think I need to get some weight out of the boat:eek:Thanks for your input Roscoe

So you are saying 5.5 gallons in a half hour?
Ouch.

There are some things to check. Like water in the floatation foam, or a fuel pump leaking fuel into the powerhead. Or the carb set too rich.
 

jerryjerry05

Supreme Mariner
Joined
May 7, 2008
Messages
18,071
Re: Fuel consuption?

Make sure the right prop is on the motor.What rpm at wot.Too heavy drops rpm.3 adults 2 kids a dog and a cooler of beer and food might be too much for a 55.Scale down the load.Only use full throttle sparingly.J
 
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