I have a new to me, 2008 340 with...

[JBD_s_Regina_Ma]

I have a new to me, 2008 340 with twin 8.1 inboards.    I have been burning gas faster in port engine vs. Star, at a pretty significant rate.   Added 86 gallons to fill for port vs 72 for Starboard.   This has happened in this range 3 times now (still getting used to my boat).   I do run the generator some, but it draws on Starboard tank, (right?).   Odd thing is, when I am trolling I run more rpms on Starboard in order to keep my batteries charged as electronics must draw on Starboard batteries.   They won't charge at idol.

Any advice would be appreciated.

[SMT]

Could be a lot of things, start at the source, carefully check the tanks to make sure you don't have a loose fitting(s). Check which tank your gen set is pulling off, if it is port change to starboard to see if it helps. Check your fuel filters to see if one has an obstruction. If your boat has sync. need to look there too! I have a 450 and the tank the gen set draws will be lower than the other by that amount in 10 hours (diesel). Figure a gen set at aprx. 1 gal hour diesel gas would be greater. Good luck!

[holiday]

I have the same boat. I changed the spark plugs, made a big difference

[PERRY2]

Check your fuel pressure on both motors. Chances are port side has a faulty fuel pressure regulator resulting to high pressure.