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Cummins 5.9 330 hp

Posted: March 12th, 2023, 11:52 am
by Fishsail
Anyone running these in a 42ish size boat? Curious about fuel burn? At slow speeds, say 7-8 knots
Tnx

Re: Cummins 5.9 330 hp

Posted: March 23rd, 2023, 8:13 am
by Fishsail
:captain:

Re: Cummins 5.9 330 hp

Posted: March 23rd, 2023, 9:08 am
by bud37
Are you experiencing more fuel usage than expected or less ?

Re: Cummins 5.9 330 hp

Posted: March 23rd, 2023, 9:17 am
by KyleR
I have twin 5.9 6BTA 370HP - not exactly the same but very similar. And we run almost exclusively at 7-8 knots (1050 - 1150 rpm), except to run the engines up near the end of each run to prevent carbon buildup.

I've been tracking it for about 5 months now and I'm averaging 3.5 gal per hour for both engines combined (i.e. 1.75gal/hrs per engine).

Also works out to about 2miles/gal overall.

Hope that helps!

Re: Cummins 5.9 330 hp

Posted: March 23rd, 2023, 12:10 pm
by Cooler
Wow! I am impressed. That seems pretty efficient. I think I will try some speeds like that with my gas engines. Just to see what my fuel burn would be. 8-) er

Re: Cummins 5.9 330 hp

Posted: March 23rd, 2023, 5:36 pm
by bud37
There is always a sweet spot somewhere between GPH and NMPG, especially concerning time/distance covered.

Re: Cummins 5.9 330 hp

Posted: March 29th, 2023, 7:59 am
by Fishsail
KyleR, yes that sounds pretty good. We’re moving over from a 6 knot sailboat so 7-8 knots is perfectly fine for us. I was hoping to get 500-600 miles on a full tank full. Tnx

Re: Cummins 5.9 330 hp

Posted: March 29th, 2023, 8:22 am
by bud37
Fishsail wrote:Source of the post KyleR, yes that sounds pretty good. We’re moving over from a 6 knot sailboat so 7-8 knots is perfectly fine for us. I was hoping to get 500-600 miles on a full tank full. Tnx


Don't forget to consider the third rule....1/3 out.....1/3 back...1/3 left over. That will cover issues, weather, currents etc. You really don't want to run boat tanks real low.

Re: Cummins 5.9 330 hp

Posted: April 20th, 2023, 2:47 am
by Y2K996
I have 6BT 215hp Cummins in my 42'LOA 390 CPMY and I consistantly get 2.3MPG at hull speed and 1MPG at cruising speed. I have wonky fuel gauges so I always fill up the saddle tanks and check my mileage and have never gotten less than 2.2MPG. Of course, my horsepower without an aftercooler is nowhere near what you have but it works for what I do with it.

Re: Cummins 5.9 330 hp

Posted: December 30th, 2023, 7:00 pm
by MV TATANKA
KyleR wrote:Source of the post I have twin 5.9 6BTA 370HP - not exactly the same but very similar. And we run almost exclusively at 7-8 knots (1050 - 1150 rpm), except to run the engines up near the end of each run to prevent carbon buildup.

I've been tracking it for about 5 months now and I'm averaging 3.5 gal per hour for both engines combined (i.e. 1.75gal/hrs per engine).

Also works out to about 2miles/gal overall.

Hope that helps!


This is excellent information, I just bought a 406 with the 370HP Cummins option and am trying to find burn data.