Fuel consumption 25 Hp Johnson

[Racex]

I have a 1974 25 Hp,Compression: 117-120 Psi,New points,Cleaned carburator with new gaskets,Now i wonder: I run it for top speed in abut 40 minutes on a light fiberglass boat,And it took about 3,2 gallons of fuel,Is this normal or is it too much?

 

[fireman57]

Re: Fuel consumption 25 Hp Johnson

Sounds about right. If I run my 50 on a 14ft fiberglass at WFO I use six gallons in about 2 hours. My old 25 on the same boat at same throttle would last about 2.5 hours. These engines are for power and speed they don't care about mileage.

 

[rwise]

Re: Fuel consumption 25 Hp Johnson

most will get better fuel milage at 3/4 throttle, just at the point the carb starts to open. I know not an answer just my 2 cents d

 

[DJ]

Re: Fuel consumption 25 Hp Johnson

Indeed. Running at 3/4 throttle will improve fuel economy by 1/3 as opposed to wide open.

 

[Racex]

Re: Fuel consumption 25 Hp Johnson

Thanks for all replys.

 

[F_R]

Re: Fuel consumption 25 Hp Johnson

I would imagine your full throttle consumption is probably normal
I have a 1984 35hp. I don't actually know how long a tank will go at full throttle because I never do that. But I do know that I can run it all day at slow speeds and stop-and-go and still have gas left. I would imagine your full throttle consumption is probably normal.