What's the approx. fuel burn with 150 hp ?

[fishmagnet]

for an update.. just went out last night. 24 miles total, 9 gallons = 2.67mpg.. decent sized swells ( trim tabs down a ways) we were going against at 24.5 mph when we went North.. flattened out for ride home (less tabs), cruised at 26 mph (burning 8.5 gall/hr) .. 2 people.. lighter load.

[phatdaddy]

and old rule of thumb for carbed outboards is 10% of hp per hour & back off 20 % rpm and cut fuel comsumption 15%, so,

150 hp = 15 gph @ 5500 rpm & at 4200 rpm 12.5 gph.

i have a 94 150 merc and i avg 2.5 mpg,so if figure with a 60 gallon tank a 120 mile range. i have no fuel guage, so i set my trip log on my gps and fill up when i get close to 100 miles and usually i can tell you within 3 gallons how much it will take.

[fishmagnet]

at 4200 I am burning 8.5-10 gph.. depending on load, seas etc.

[THEFERMANATOR]

Originally Posted by fishmagnet

at 4200 I am burning 8.5-10 gph.. depending on load, seas etc.

Is that a 2.4L 175 MERC? I know my 2.5L 150 MERC XRI on a flats boat would gulp down about 13-14 GPH at 4200.

[bgreene]

Think we're still talking a 150 hp outboard.

[Cam]

BGreene, What size wheel are you turning?

[Wolf]

There are several ways you can do this. Conditions odviously make a difference. But, everyone wants to know how far can I go on a gallon of gas. I went out of ponce inlet a few days ago with my wife and two kids. I had exactly one gallon of gas in a milk jug, unplugged the fuel line from the engine stuck into the jug and took off. I reset my Chart plotter brought it up on plane like I normally would. Trim the engine and settled in at 3500rpm. Which is about 28 mph. and watched the fuel filled milk jug empty at a alarming rate. It's interesting to see how much fuel these old two strokes burn especially when you can actually see the fuel level drop. It gave the kids an idea of how expensive it really is to go tubing :)

The results were in:
Boat: 1978 V20 Cuddy
Engine: 1987 150 Suzuki Super Six
Load: About 25 gallons of fuel on board two adults and two kids 12 and 9
Sea Conditions: 1' (calm)
RPM. 3500
Speed: 28 mph
Gas mileage: 3.04 miles per gallon
Not to shabby for an old 2 stroke

[bgreene]

Now that's what I call accuracy !

Interesting - that's just about what the old brochure indicated the boat range - around 180-200 miles max with a 150 hp.

So using your formula, those of us with clean hulls, and solid 150hp's can fish out 60 miles, 60 miles back......with 1/3rd reserve......better make that 50 miles out and back for more safety.

And ps.......bring along an extra full 10 gallons back up.

Thanks for your report.

[randlemanboater]

Originally Posted by THEFERMANATOR

Is that a 2.4L 175 MERC? I know my 2.5L 150 MERC XRI on a flats boat would gulp down about 13-14 GPH at 4200.

Hey Ferm, a friend of mine is looking at a 94 18' Nitro with a 150 XRI on it, would you think fuel burn would be the same on that rig?

[THEFERMANATOR]

Originally Posted by randlemanboater

Hey Ferm, a friend of mine is looking at a 94 18' Nitro with a 150 XRI on it, would you think fuel burn would be the same on that rig?

Yes. the XRI is a great engine, but it is known to be a thirsty pig as MERCURY made em run a bit rich so they would last longer on the bass boats. It is the same basic engine as an XR6, but the carbed XR6 was actually a little better on fuel I was told. It was a great running engine though, and always ran smooth and would troll for hours and never stall.