86 merc 60hp outboard runs good but seems to use way too much fuel???

[darrenz]

motor is on a 13ft fantasy speed boat which is pretty light and little resistance.it does smell to be running a little rich when trolling through no wake zones,runs fine but I would say im burning about 7-8 gal in prob 10-15 miles????does that seem right? I am mechanically inclined just need to know what to adjust. thanks.

 

[oldman570]

Re: 86 merc 60hp outboard runs good but seems to use way too much fuel???

Fuel usage can be more depending on the RPM, prop pitch, and weight of the boat. If the motor is being lugged down and not running up to the recommend RPM the fuel will go fast. The prop pitch and weight of the boat will cause this trouble. You can go to the prop forum here and see if this could be your trouble. The prop calculator on here and other sites will help with more info for your setup. If the motor is run at WOT the entire time fuel will go fast and running the motor at a lower RPM while still on plane should help some. The fuel mileage on marine motors is usually less than 3 or 4 miles a gallon on a well tuned motor and a lot less if used to pull skiers or tubes. If a motor is leaned out to much, chances of damage to the motor is increased. JMO
Oldman570

 

[darrenz]

Re: 86 merc 60hp outboard runs good but seems to use way too much fuel???

thanks for the info...I was gonna look into prop etc before stricktly to see if I had available rpms to make faster but when someone swapped motor yrs ago they never hooked up tach and im not sure if this tach has setting for 3cyl.this controller has a plug that plugs into controller for tach and of course that's missing so maybe ill look into getting tach up and running first. I have been basing on what my 25hp boat,and 115 boat had used and the fact that friends 18ft w 6cyl inboard uses less than me.i think boats under 1000 lbs and turns about 40mph so I think its at least close.