If it helps your planning for fuel burn, figure that pair of engines will burn about 30 - 32 gph combined in the 3200 - 3300 rpm range. Down at 1300, you should be around 5 - 5.5 gph combined. 1500 rpm will be around 6 - 7 gph. If you're up for tinkering, you can save a little fuel at low rpm (under 1500 or so) by leaning out the idle mixtures on the carbs a bit. You can usually go a bit leaner than most would set them and still get a good idle.
Thanks for the data. We only "own" this boat for a couple of weeks; so no tinkering allowed!
Well, I did adjust the linkage for the rudder indicator today. Damned thing was reading half left rudder when amidships.
Need a hole saw - no drink holders at the helm. Sacrilege.
We ran at 2400 most of today making around 11 MPH in still water (although sometimes below dams we ran 13 for awhile) for 59 miles. Burned 79 gallons. 7.5 hours total time with an hour-plus waiting on locks (four of them today). Say maybe 13 gallons an hour.
At the 3000-plus RPM setting I would arrive in Demopolis with around 20 gallons per tank, eek!
We are also having to run the 8.2 KW generator a goodly portion of the days to keep from freezing to death. I get cold death stares from Mary when I tell her to wear more clothes or to stand on her head to elevate her cold feet up to the warmer air.
Winds today were light, and lock-luck was outstanding as no tug traffic was observed except one running north before dawn this morning at Midway Marina. Apparently this is the annual slow time for commercial traffic on the Tenn-Tom. Water levels are nominal, and except one ten-mile section below a fast running side tributary, junk in the water has been minimal.
We have 119 miles and three more locks and one overnight anchorage before we gain Demopolis and our next fuel. At our average of 80 gallons of gasoline a day for the two past 60-mile days at 2200 to 2500 RPM, we should arrive with about 1/3 of our fuel remaining. This big 57-foot Marlowe we have been keeping company with for the last two days could drag us along, I suppose.
Funny story. The Marlowe swapped into my spot at the fuel dock this morning at dawn as I departed with the intention of catching up at the second lock after getting some "insurance" diesel. Seems nobody knew there was no diesel in the marina tank. Maybe we'll tow him. There's an image, dumpy box boat towing a big Marlowe GB wannbe. There is no red or yellow boat towing service way out here....