Fuel Consumption Difference between Port and Starboard

[amberjack290]

I have a 2007 290 Amberjack with T-350 Mag MPI Bravo III (about 75 hours). I bought the boat used this year and have only put about the last 10 hours on it, but have a question about fuel economy.

Based on gage readings it appears the port engine uses fuel at a faster rate. Also, at my first top-off the port tank took slightly more fuel (about 12 gallons) than the starboard tank and seemed to confirm the gage difference.

No performance issues. No alarms, warnings, codes, etc.

Has anyone experienced something similar? What kind of fuel economy should I expect?

Thanks for the help.

 

[my3sons]

What's the difference in burn rate? My Starboard burns slightly more than port, almost half a gallon per hour at cruise speed. That is not unusual. If your burn rates between motors are significantly different, then it may be something you have to look into.

 

[Aerobaticflyer]

Have you confirmed your two tanks capacity? Often one is larger than the other. Won't change consumption but affects gallons remaining. Also gauges need to be calibrated correctly to match tanks capacity.....verify that.

Generator, if you have one, draws a little out of one side.....

Have you watched your fuel consumption rate on each side to see if you're consuming equally? You can compare tachs to see if load is equal and then confirm fuel flow is equal.

 

[amberjack290]

I need to top off again to confirm, but based on last top off and rough calculation it appears it could be burning as much as 1-1.5 gph more at cruise (3400 rpm).

 

[amberjack290]

Aerobaticflyer - Thanks. The boat was a repo and had no manuals (I'm accumulating everything now), so I'm still not up on all the smartcraft functions to find fuel consumption. All i've seen so far is combined, instantaneous FE. I'll look for fuel burn on each.

 

[HUMPH]

I have the same issue. My port side uses more fuel than the starboard. I know my genny is from the port side but I ran a new tank and never strted the genny and it still reads way different. I was thinking the sending unit maybe is bad?

 

[aQUANAUTT]

Ken, I noticed the same thing with my T5.7 w/carbs. The port eng burned about an extra .5 to 1/per mile. Measured with twin Garmin GPS 10 gas flow meters. A change in spark plugs for the port gave it the advantage and now it gets about .5 to 1/per mile better than the starboard. An easy test is replace both and see if they are even. Good luck.