6cta8.3 fuel burn

[Woody]

I ran my boat home weekend before last, 6cta8.3, 485 mile trip. I fueled up three times and each time the port side used more fuel than stbd. After totaling up for the whole run it shows port side burning 16% more fuel than stbd. Generator was never used during trip.

The engines both were able to turn 2,725rpm at WOT, new fuel filters installed for trip, props had no visible damage at all, no vibrations while running, engines sounded good/smooth while running, air filters ‘looked’ clean, both engines ran at 165 degrees, engines had 580hrs so valves were set prior to trip.

Some smoke and fuel on water when cold and idling. No visible smoke when warmed up and running. Glendinning engine sync appears/sounds to be working properly. It purred along pretty nicely and the last day ran 225 miles without a stop.

Port side used 16% more fuel….why? What do you guys make of this?

 

[swaterhouse]

My starboard engine does the same thing, burns about 1 gal/hr more than port. Computer shows starboard load is about 6% higher than port at same RPM, I plan on tuning props this winter as that is the most likely cause. Because of this I have been running at about 2360 RPM to keep the load at around 80% for starboard. All the recent mechanical work (boat is new to me this year) was on starboard engine, no repairs at all on port.

 

[FeLizDream]

I ran my boat home weekend before last, 6cta8.3, 485 mile trip. I fueled up three times and each time the port side used more fuel than stbd. After totaling up for the whole run it shows port side burning 16% more fuel than stbd. Generator was never used during trip.

The engines both were able to turn 2,725rpm at WOT, new fuel filters installed for trip, props had no visible damage at all, no vibrations while running, engines sounded good/smooth while running, air filters ‘looked’ clean, both engines ran at 165 degrees, engines had 580hrs so valves were set prior to trip.

Some smoke and fuel on water when cold and idling. No visible smoke when warmed up and running. Glendinning engine sync appears/sounds to be working properly. It purred along pretty nicely and the last day ran 225 miles without a stop.

Port side used 16% more fuel….why? What do you guys make of this?

Woody
How much fuel your boat spend at cruising speed?



FeLiz Dream
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[Woody]

I replaced the air filters. What I found especially bad on the port engine was the bottom third or more was oil soaked and loaded up with dog hair. It was oil soaked to the point when I set it on end oil leaked all over...it didn't leak when horizontal on the engine. I got an immediate increase in mpg but the port side is still using more than strbd. I usually cruise 2,300-2,350 and am now hitting 1.0mpg.

I think I need to get Cummins in to look at the port engine. It seems to leave a bit of fuel on the water even after being warmed up and also when accelerating I'll get a puff of black smoke when I shouldn't. I'm thinking maybe an injector problem.