Fuel Consumption on 150 Johnson

[donhv]

I'm the proud new owner of a 1994 Johnson 150hp non VRO. It starts, runs, and idles very good. My only concern is this engine's love for gasoline. I think she's drinking about 18 to 20 gallons per hr. I usually run at or near WOT. What should it use. It's on a 20' Bay Hawk (shallow water hull) and has a 19" Viper SS prop
Thanks for your comments
donhv

 

[angus63]

Re: Fuel Consumption on 150 Johnson

Should use closer to 15 gph at wot depending on load. What is your WOT rpm? Are you pulling someone or transporting a baseball team?

 

[lexkyboater]

Re: Fuel Consumption on 150 Johnson

My understanding is that 100 HP should pull about 11 gallons per hour at WOT. I think I read it's around 1 gallon per 10 HP. My 93 Yamaha 115 also seems like it's got a hole in the tank. I brought extra gas when we spent 1/2 day tubing/kneeboarding a few weeks ago, but with a full tank, it only used about 12 of the 17 gallons with stop and go operation. Wasn't too bad, but almost makes me want an I/O. Shame that you get punished for running the thing...

 

[donhv]

Re: Fuel Consumption on 150 Johnson

hi Ang,
RPM about 5K, and loaded with less than 800 lbs. (2 adults, 2 kids, and gear).
Previous engines were 70 looper, and 115 Evinrude, both from the 80's. It isn't the fuel cost, just the prospect that I could have a problem.
thanks
donhv

 

[VTXMatt22]

Re: Fuel Consumption on 150 Johnson

It seems like a lot to me. I have a VRO 150 on a 20' deep V center console, and burn half that amount. If you keep the RPM's down below 4000, you will save a lot of fuel.
Matt

 

[tashasdaddy]

Re: Fuel Consumption on 150 Johnson

these motors are set up with a type of cruise control. if you go to wot, and then throttle back to around 7/8ths, the carb butterflies close some, but the spark stays advanced. you will lose 2-5 mph, but will gain a lot of fuel economy.

 

[Silvertip]

Re: Fuel Consumption on 150 Johnson

The total amount of fuel burned depends on the burn rate (gallons per hour) and the speed you travel. While a slower speed results in burning less fuel (GPH) it takes you longer to get where you are going than if you ran wide open so fuel savings over a given distance is not as much as one would think. Later today I will post a long article on the "Boat Topics and Questions" forum dealing with four identical boats, and four 75 HP engines (two carbed two strokes, one four stroke and one Evinrude E-tec). The charts confirm this exact point.

 

[angus63]

Re: Fuel Consumption on 150 Johnson

Just for reference....
my 1995 175 oceanpro pushes 21.5' trophy about 25-30 mph at 3800-4000 rpm and burns 8-10 gph. Load,wind and tide makes some difference. Tops out around 40 mph at about 5400 rpm. Never run at WOT long enough to know what she drinks there!!!! Use a 4 blade 15-1/2 x 16 aluminum reworked prop.

 

[rndn]

Re: Fuel Consumption on 150 Johnson

Keeping the rpm's down just a little bit can save huge amounts of gas. It's not worth the extra 5-10mph for the huge increase in fuel consumption. It's also a bit easier on your powerhead.