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

Got a 96' 150 Johnson looper on my 96' V21. Both in great condition.......motor making full compression, and less than 200 hours on it.


So question is......at best cruising rpms, figure 4,000 what's the approx. fuel burn.

Approx. is fine. I haven't taken the time to fill, run, re fill, measure.

Figure you boys know from experience.

Thanks

my merc 175 black max on a 78 V20 in moderate seas with three people onboard burns 9.5 to 10 gph.. at 25-26mph.. this is direct info from my flowscan and has been accurate

Ok so at 25mph for 6 hours.........assuming calm / flat seas............we're out of fuel at approx. 150 miles.

Allowing the 1/3rd safety reserve, that's just about 50 miles out, and 50 back maximum.

Not exactly a Canyon rig, but that's not what the V's are intended to do.

The OMC 60 degree engines are known as being ZTHIRSTY, but make up for it with reliability. I would figure closer to 11-12 GPH at 4K RPM's.

Well i guess that depends on what size tank you got! I made mine 85 usable gallons... in flat/calm i get a touch over 3mpg... i like to figure mine out at
80 gal x 2.2 = 176 mile range.. which for southern california is enough for a 20' boat for offshore stuff

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.

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.

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.

Think we're still talking a 150 hp outboard.

BGreene, What size wheel are you turning?

Fuel burn
 

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

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.

This weekend I hooked up my new Lowrance gps. With 3/4 tank I was getting 3.4 mpg at 4200, 3.6 mpg at 4600, and 3.1 mpg at 5100. This is with a 120 looper and bottom paint. I was in 1-2 foot chop with two people on board. If I dropped down to 3500 my mileage fell to 2.1, and at 5700 I was still getting 1.9.

Original V21 brochure claimed 230 mile range so.........that would mean
3.8 miles per gallon at cruise with the 60 gallon tank.

Anyone getting that range ?

I can tell you this - by reducing my trailering speed from 65 to 55 my Ford Explorer towing fuel economy improved by 20% from 10 to 12 mpg.
So now I tow at 55 mph. A no brainer because over a 1hr drive that's 10 miles which only costs me an exta 11 minutes drive time.

Ran about 70 miles yesterday, Sunday off NJ coast and burned around 28 gallons.

I wasn't running for maximum efficiency, cruising approx. 4,600 rpm.

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.

Thanks Ferm, I'll pass on the info. He really likes the boat, but he really likes the fuel burn on the Bass Tracker TX-17 with the 40hp Merc he has now.

The fuel burn is porbably the only reason I sold my PROLINE. I loved the HP and speed, but it drank as much fuel in a day as my HYDRA-SPORTS did with a built 225 going simliar speeds. I should have broke down and bought an OPTI and hung on that flats boat as I kick myself daily for selling that boat.