94 johnson 150 fuel consumption

[JBerg]

I have a 94 Stratos F/S w/150 johnson, which seems to use an enormous amount of fuel. The compression runs 100-105, the carbs have been rebuilt, the VRO has been disconnected, and the prop is a renegade 4 blade 13/21. Also at slow speeds it doesn't seem to run real smooth. Also it has new s/plugs. Is it possible that the 4 blade prop would cause this. Ive tried everything else that I can think of, any help would greatly be appreciated. Thanks

 

[JBerg]

Re: 94 johnson 150 fuel consumption

Additionally I usually run around just 30-40 miles per hour

 

[jonesg]

Re: 94 johnson 150 fuel consumption

15 gals an hr is typical at WOT,
what RPM's do you get?

 

[JBerg]

Re: 94 johnson 150 fuel consumption

Anywhere from 3000-4000

 

[jonesg]

Re: 94 johnson 150 fuel consumption

4000 max at WOT ?
Should be well over 5K
You sure its running on all cyl's?

 

[Chris1956]

Re: 94 johnson 150 fuel consumption

That prop may be a bit tall for that boat. I run a 19P prop on my 21footer with a Johnny 150HPV6, and that is a bit on the tall side.

 

[jonesg]

Re: 94 johnson 150 fuel consumption

I run a 19p 3 blade on mine too....same engine.